Keynote Sessions
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Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil Interfaces for Sustainable Development 5th – 10th July, 2015 McGill University, Montreal ABSTRACTS JOINT MEETING OF Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Table of Contents Keynote Sessions ...................................................................................................................19 PLENARY SPEAKER ......................................................................................................................... 20 Changing Concepts of Organo-Mineral Interactions in Soils: Impacts on Soil Properties and Sustainable Development ................................................................................................................... 20 SESSION 1 ........................................................................................................................................... 20 Thermodynamics and kinetics of plant iron acquisition ..................................................................... 20 SESSION 2 ........................................................................................................................................... 21 The Contributions of Heritable Variation, Soil Chemistry, and Meteorological Conditions in Accumulation of Cd by Glycine max in Ontario .................................................................................. 21 SESSION 3 ........................................................................................................................................... 21 Soil microorganisms – architects and actors of biogeochemical interfaces ....................................... 21 SESSION 4 ........................................................................................................................................... 22 Organo-mineral associations at different levels of soil aggregate hierarchy: What do we get from physical fractionation? ........................................................................................................................ 22 SESSION 5 ........................................................................................................................................... 22 Advances in the characterization of soil organic matter and speciation of major nutrient elements by the application of complementary mass spectrometric and synchrotron-based X-ray spectroscopic methods ....................................................................................................................... 22 SESSION 6 ........................................................................................................................................... 23 Nitrogen Fertilization and Soil N2O Emissions..................................................................................... 23 SESSION 7 ........................................................................................................................................... 23 Role of iron oxides in controlling organic P cycling in soil ................................................................... 23 SESSION 9 ........................................................................................................................................... 24 Soil Science Education with K-12 students in Canada ......................................................................... 24 SESSION 11 ......................................................................................................................................... 24 Ecosystem-scale methane fluxes in Canadian wetlands ..................................................................... 24 SESSION 12 ......................................................................................................................................... 25 Proximal multi sensor system for measuring soil condition ............................................................... 25 SESSION 13 ......................................................................................................................................... 25 Scales and scaling in soils: Soilscope for soilscape .............................................................................. 25 SESSION 15 ......................................................................................................................................... 26 Historic Barriers to Biochar Utilization: Is there a way to avoid these same hurdles? ....................... 26 1|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 17 ......................................................................................................................................... 26 Restoring organic matter processes in reconstructed soils................................................................. 26 Oral Sessions ..........................................................................................................................27 S1: Macro and Micronutrient Dynamics in Soil.......................................................................... 28 Soil properties and not inputs control the carbon, nitrogen, phosphorus relationships in cropped soils ..................................................................................................................................................... 29 Following the Fate of Different Sulfur Fertilizers in Prairie Soils ......................................................... 29 A field microcosm study to investigate phosphorus release from Manitoba soils under prolonged flooding ............................................................................................................................................... 30 Soil Phosphatase and Phytase Activities in Canola and Wheat Rhizospheres during the Growing Season ................................................................................................................................................. 30 The effects of cover crops on phosphorus cycling in agricultural soils of California .......................... 31 Tillage Practice and Phosphorus Fertilization Effects on the Distribution and Morphology of Corn Root ..................................................................................................................................................... 31 Impact of Phosphorus Fertilizer Placement on Crop, Soil, and Run-Off Water in a Brown Chernozen in South-Central Saskatchewan........................................................................................................... 32 Crop agronomic responses to phosphorus-based swine manure application and manure phosphorous source coefficients under long-term corn-soybean rotation ........................................ 32 Organic matter distribution across particulate and mineral-associated fractions varies directly and interactively with cover cropping and tillage management................................................................ 33 Nitrification occurs in frozen agricultural soils – consequences on fate and management of fallapplied and soil residual N under cold climate ................................................................................... 33 Impact of Cover Crops and Organic and Mineral Fertilization on Canola Yields and Nitrogen Uptake ............................................................................................................................................................ 34 Nitrogen application rate, timing and history effects on corn nitrogen use efficiency....................... 34 Effect of organic matter on nitrogenase metal cofactors homeostasis in the soil bacterium Azotobacter vinelandii under diazotrophic conditions ....................................................................... 35 Origin of inositol phosphates in residual fractions derived from Hedley fractionation in Chilean Andisols ............................................................................................................................................... 35 S2: Dynamics of Pollutants in Soil ................................................................................................ 36 Environmental model of P saturation for acidic soils of Prince Edward Island ................................... 37 Application of the Root Zone Water Quality Model (RZWQM) to stimulate fate and transport of emerging substances of concern in soils receiving long-term biosolids application .......................... 37 Dynamics of PAH and derived organic compounds in a soil-plant microcosm spiked with 13Cphenanthrene ..................................................................................................................................... 38 Assessment of triclosan toxicity to the earthworm Eisenia fetida under laboratory conditions using GC-MS metabolomics.......................................................................................................................... 38 2|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Conservation of insecticidal activity of CrylAc adsorbed on three contrasting soils and persistence with time ............................................................................................................................................. 39 Sorption and Desorption Kinetics on Mixtures of Non-Steroidal Anti-Inflammatory Drugs in Different Textured Agricultural Soils................................................................................................................... 39 Evaluation of soil microbial communities as influenced by cruel oil pollution ................................... 40 The assessment of non-point-source of contamination on the Kinetics of some potentially toxic elements desorbed from contaminated soils ..................................................................................... 40 Heavy metal concentration in soil in the Tailing Dam Vicinity of an Old Gold Mine in Johannesburg, South Africa ......................................................................................................................................... 41 Experimental assessment of copper and cobalt phytoavailability in soils from metalliferous ecosystems in Katanga ........................................................................................................................ 41 A correlation between nickel/ metal mineralogy and its bioaccessibility in artificial (OECD) spiked soils ..................................................................................................................................................... 42 Adding silver nanoparticles to soils directly or in biosolids leads to differences in Ag speciation. .... 42 Influence of Mowing and Narrow Grass Buffer Widths on Reductions in Sediment, Nutrients, and Bacteria in Surface Runoff................................................................................................................... 43 S3: Soil Microbiology ........................................................................................................................ 44 Microbial Resource Partitioning in Microhabitats of Soils .................................................................. 45 Influence of substrate availability and environmental conditions on microbial communities and enzyme activities in topsoil and subsoil habitats ................................................................................ 45 Stability of buried soil organic matter in cropland: What are the mechanisms?................................ 46 Methanogen community responses to a gradient of sulfur and metal contamination in Sudbury, ON peatlands............................................................................................................................................. 46 Effect of Zeolite and Bacteria on Straw Decomposition and Greenhouse Gas Emission from Paddy Field ..................................................................................................................................................... 47 Short-term shifts in fungal community structure accompanying soil disturbance: observations from a six-month microcosm study ............................................................................................................. 47 Carbon limitation constrains soil microbial activity and influences microbial community composition in soils under organic management .................................................................................................... 48 Rhizospheric bacterial proteolytic communities under the influence of plants with different nitrogen uptake rates......................................................................................................................................... 48 Genotype-specific variations shape the structure of root fungal communities and determine the response of chickpea to symbiotic fungi............................................................................................. 49 S4: Organo-Mineral Interactions in Soil ....................................................................................... 50 Spatial distribution of soil organic matter across density fractions of soil day nanoparticles: STXM chemical mapping ............................................................................................................................... 51 Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized 3|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 particles ............................................................................................................................................... 51 Character of Organic Matter in Deep Soils of Temperate Forest Ecosystems ..................................... 52 Choice of extraction cocktail to remove contrasting proteins from reference soil minerals with a view to soil metaproteomic analysis ................................................................................................... 52 The role of temperature and soil texture in decomposition: findings from a physical fractionation study.................................................................................................................................................... 53 Kinetic, Thermodynamic and Conformational Insights of BSA Adsorption onto Montmorillonite Revealed Using In-Situ ATR-FTIR/2D-COS............................................................................................ 53 S5: Analytical and Methodological Advances in Soil Study ................................................... 54 The Structure, Associations and Interactions of Soil Organic Matter in-situ using Comprehensive Multiphase NMR Spectroscopy ........................................................................................................... 55 Unbiased statistical analysis of soil 31P-NMR forms using compositional concept ............................. 55 Integrated Light Element X-ray Excitation Emission Spectroscopy: Speciation, Diffraction, Quantitation in one soil analysis ......................................................................................................... 56 Determination of phthalates in soils and biosolids using accelerated solvent extraction coupled with SPE and GC-MS.................................................................................................................................... 56 Propericiazine as a Selective and Sensitive Reagent for the Spectrophotometric Determination of Microgram Amounts Platinum in Minerals ......................................................................................... 57 Comparison of in vitro estimates of bioaccessible Ni in field-contaminated soils and identification of mineralogy .......................................................................................................................................... 57 Approximating Soil Respiration and Belowground Biomass on the Qinghai-Tibet Plateau with Different Empirical Models ................................................................................................................. 58 Studying Natural Root Systems in Soil of the Semi-Arid Region of Brazil ........................................... 58 Permanganate-oxidizable carbon as a soil quality indicator in agricultural upland systems of Southeast Asia..................................................................................................................................... 59 Impact of changes in sample preparation parameters (drying, grinding and sieving) on soil characterization of coarse-textured results in Quebec ....................................................................... 59 Determination of the fixation sites of metal trace elements in lake sediments from taïga and toundra forest with a scanning electron microscope ......................................................................... 60 S6: Agricultural Greenhouse Gas Emissions ............................................................................. 61 Farm-scale assessment of greenhouse gas mitigation strategies in dairy livestock-cropping-systems ............................................................................................................................................................ 62 Net ecosystem exchange of dairy cropping systems........................................................................... 62 Effects of dairy manure management in annual and perennial cropping systems on N-cycling microbial community structure and associated in situ N2O fluxes ..................................................... 63 Farm-Scale Estimation of C Sequestration and Greenhouse Gas Mitigation by White Spruce Shelterbelts: HOLOS, 3PG and CBM-CFS3 simulations ......................................................................... 63 4|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Contribution of Soil N2O Emissions from Fall Alfalfa Plow-down in Organic Cropping Systems ......... 64 Nitrous oxide gas flux, emission factor and emission intensity following termination of perennial grass .................................................................................................................................................... 64 Silvopastures and trees increase the size and stability of carbon pools in agroforestry systems of western Canada .................................................................................................................................. 65 Storage and stability of soil organic carbon under shelterbelt agroforestry systems ......................... 65 Effect of microirrigation type, N-source and mulching on nitrous oxide emissions in semi-arid climate: An assessment across two years in Merlot grape vineyard .................................................. 66 Managing fertilizer nitrogen application methods and N sources to improve crop performance and reduce ammonia volatilization and nitrous oxide emissions .............................................................. 66 S7: Chemical and Biological Controls on Organic P Cycling in Terrestrial and Aquatic Environments ...................................................................................................................................... 67 On new opportunities and techniques for advancing the study of soil phosphorus .......................... 68 Gross P mineralization and microbial P uptake in forage field soils along a soil test P gradient ........ 68 Influence of soil pH and inorganic phosphate levels on glyphosate sorption .................................... 69 Phosphorus containing water dispersible nanoparticles in arable soil ............................................... 69 Fate and transport of labile DNA- and Phospholipid-phosphorus through a grassland catchment transfer continuum ............................................................................................................................. 70 Phosphorus of colloidal forest soil fractions as revealed by Field Flow Fractionation and liquid-state 31 P-NMR............................................................................................................................................... 70 Temporal characterization of phosphorus forms, bioavailability, and mobility in Lake Champlain sediments ............................................................................................................................................ 71 Phosphorus Nanoparticles and Colloids of Forest Stream Waters – Fractionation and Potential Role in Ecosystems ...................................................................................................................................... 71 A comparison of phosphorus forms and concentrations in midden samples and forest soils from Calvert Island, BC arable soil ............................................................................................................... 72 S8: Microbial Provision of Essential Services across Managed and Natural Ecosystems ................................................................................................................................................................ 73 Apatite and orthoclase forest fertilization: insoluble phosphorus and potassium made available by ectomycorrhizal fungi and associated bacteria................................................................................... 74 Interactions of ammonium oxidation pathways in soil environments from Southern China ............. 74 The role of arbuscular mycorrhizal fungi in carbon cycle of agroecosystems..................................... 75 The amplitude of soil freeze-thaw cycles influence temporal dynamics of N2O emissions and denitrifier transcriptional activity and community structure ............................................................. 75 Influence of 4-Year Crop Rotations on the Structure and Function of the Root Endosphere Community and Performance of Wheat ............................................................................................. 76 Historical Rotation ABC: changes in microbial community dynamics over 100 years of wheat 5|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 production........................................................................................................................................... 76 Study of soil bacterial, fungal and microfauna diversity in potato agroecosystems using high throughput sequencing ....................................................................................................................... 77 Effect of four previous crops on potato yield and tuber quality and their impact on soil and rhizosphere bacterial community ....................................................................................................... 77 S9: Soil Science Education and Outreach .................................................................................. 78 Innovation and Creativity: Practical Application in Soil Science Field Courses ................................... 79 Envirothon: Hands-on soils education for secondary schools students – a soils professional perspective .......................................................................................................................................... 79 Environthon: Hands-on soils education for secondary school students – a student perspective ...... 79 Soil Science Education for Non Soil Science Professionals .................................................................. 80 Real life soil stories: an untapped resource ........................................................................................ 80 “La forêt m’invite”: A wild leek conservation project for high school students ................................. 81 Planting Seeds of Knowledge in Soil. How to Get Children’s Hand (Scientifically) Dirty .................... 81 S11: Wetland Soils in a Changing Climate .................................................................................. 82 Impacts of soil drainage conditions on soil heterotrophic respiration along a temperate agricultural hillslope transect ................................................................................................................................. 83 Agricultural Surface Drainage and Changes in Soil Properties in Eastern Saskatchewan ................... 83 Assessing pedogenic controls on carbon mineralization, organic matter composition and microbial community dynamics in a mountain peatland.................................................................................... 84 Differences in CH4 production, storage and transport among plant community types during a wet summer at Mer Bleue bog, Ottawa..................................................................................................... 84 Patterns of Microbial Enzyme Activity across Three Temperate Canadian Peatlands ........................ 85 S12: Proximal Soil Sensing ............................................................................................................. 86 Enhancing Digital Elevation Models for Improved Soils Mapping ...................................................... 87 Three-dimensional soil mapping using proximal soil sensors ............................................................. 87 A Comparison of Machine Learning Techniques in Digital Soil Mapping for the Lower Fraser Valley, British Columbia .................................................................................................................................. 88 Does Increasing Complexity of Tree-Based Classifiers Improve Prediction Results in Digital Soil Mapping? ............................................................................................................................................ 88 Proximal sensors for site-specific fertilization: A case study in maize crops in Colombia .................. 89 Diagnosis of a drainage system based on GPR imagery in cranberry production .............................. 89 Defining the spatial heterogeneity of soil biological activity .............................................................. 90 Statistical variability of soil test NO3-N and the management zone concept ..................................... 90 S13: Spatial and Temporal Dynamics of Soil Processes and their Interactions at Multiple Scales to Study Complex Soil Systems ....................................................................... 91 6|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Spatial and temporal variation in soil nitrogen supply in potato cropping systems in Prince Edward Island ................................................................................................................................................... 92 Spatial Variability of Soil Physical and Thermal Properties in Ituri Forest, Democratic Republic of Congo .................................................................................................................................................. 92 Spatial variation in soil bacterial communities in a commercial potato field ..................................... 93 Mapping Temporal and Spatial Soil Hydrothermal and Mechanical Properties by way of the Soil Trafficability Prediction Model (STRAP) .............................................................................................. 93 The impacts of changing rangeland into forest park on availability of heavy metals ......................... 94 Scale-variability of surface microtopography on a highly-stable soil under simulated rainfall........... 94 Scaling mineral nitrogen dynamics by soil aggregate size .................................................................. 95 S14: General Soil Science ............................................................................................................... 96 25th Anniversary (1990-2015) Findings from the Lethbridge Simulated Erosion Study ...................... 97 Seeding various types of cover crops to winter wheat stubble in southwestern Ontario .................. 97 Tile drains as modifiers of source and transport factors for nutrient exports from agricultural fields ............................................................................................................................................................ 98 Prediction of hydrophysical properties of soils for sustainable land management in DR Congo ....... 98 Ammonia and nitrous oxide emission factors of land applied cattle manure in Alberta and Ontario 99 Model development and testing of soil temperature in DNDC for the effects of snow, biomass and residue cover and soil texture ............................................................................................................. 99 Soil pH is a good predictor of dominating N2O production pathways under aerobic conditions ..... 100 Comparison of nitrous oxide emissions from a gray soil subject to different long-term fertilizer and manure applications at the University of Alberta Breton Plots ........................................................ 100 Soil Nitrous Oxide Emissions from Cropland in Southern Manitoba ................................................ 101 Nitrifier and denitrifier abundances in vineyard soil in response to agricultural management practices ............................................................................................................................................ 101 Metaproteomics of soil and leaf litter – Potentials and Challenges ................................................. 102 Soil carbon stocks and tillage intensity in organic farming systems: a meta-analysis ...................... 102 Nitrogen release from decomposing legume crop residues over three subsequent crops .............. 103 Hyperspectral Vegetation Indices for Detecting In-Season Nitrogen Stress in a Potato Crop .......... 103 Nitrogen and phosphorus fertilization in wild lowbush blueberry in Quebec .................................. 104 S15: Biochar in Agriculture and Environment/ Le Biochar en Agriculture et en Environnement ................................................................................................................................. 105 Biochar production: a tool to mitigate climate change..................................................................... 106 Biochar amendment alters the molecular-level composition of soil organic matter in a temperate forest soil ........................................................................................................................................... 106 Charcoal amendment changes soil carbon dynamics through its impact on (micro-) biological 7|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 functioning after several centuries ................................................................................................... 107 Does a Meat and Bonemeal Biochar Enhance Petroleum Hydrocarbon Degradation in Frozen Soil? .......................................................................................................................................................... 107 Use of Biochar as a Soil Amendment for Fertility Improvement in the Sandy Soils of Labrador...... 108 Soil CO2 and N2O emissions: Is the mitigation efficiency of biochars impacted by periodic applications of mineral nitrogen fertilizer? ....................................................................................... 108 Mineral based nutrient dynamics of dual feedstock biochars under increasing pyrolysis temperatures .................................................................................................................................... 109 Mechanisms of soil pH regulation by biochar amendments and consequences for biochar long-term effects................................................................................................................................................ 109 Biochar as a component of potting soils: case studies ..................................................................... 110 Impact of rice husk biochar on selected soil properties of two Alfisols of Sri Lanka ........................ 110 Adsorption of copper by pine sawdust biochar in synthetic oil sands process-affected water ........ 111 S16: Management Zones in Precision Agriculture/ Zones d’Aménagement en Agriculture de Précision ................................................................................................................ 112 High-resolution elevation data (h-red) clouds generated on-farm facilitate detailed soil mapping and precision management of Ontario farm fields .................................................................................. 113 Response of corn to N rates as a function of soil properties in a precision farming context ........... 113 Multi-temporal, multi-parameter geospatial data sets facilitate detailed soil mapping of Ontario farm fields ......................................................................................................................................... 114 Sustainable cropping system management zones: a central role for intrinsic soil properties, landscape feature delineation .......................................................................................................... 114 The Spring Nitrate-N Soil Test can improve the General N Recommendation for Corn Production on a Clay Loam in Southwestern Ontario ............................................................................................... 115 Managing soil interfaces with 4R crop nutrition ............................................................................... 115 Irrigation strategies for strawberry in California and Quebec: yield, water savings and return on investment ........................................................................................................................................ 116 Development of a real-time method for assessing subsurface drainage systems performance in cranberry production ........................................................................................................................ 116 Controlling water table depth for a sustainable cranberry production ............................................ 117 S17: Soils of Natural, Managed and Intensive Forest Systems/ Les Sols de Systems Forestiers Naturels, Aménagés et Intensifs .............................................................................. 118 Nutrient and trace metal leaching in boreal and temperate forest soils following wood ash applications ....................................................................................................................................... 119 Restoring a disturbed clayey forest soil using dehydrated sewage sludge ....................................... 119 Wood Ash as a Forest Soil Amendment: Seedling growth responses, and responses of red-backed salamander populations ................................................................................................................... 120 8|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Leaf litter and deadwood decomposition in boreal stands as a function of species, litter type and harvesting prescription: A 12-13 year litterbug experiment............................................................. 120 Environment and genotype control on foliar, fine root and litter traits in mature hybrid poplar plantations ........................................................................................................................................ 121 Forest floor heterogeneity modulates fungal activity and C mineralization in boreal forests .......... 121 Changes in soil conditions and foliar nutrition of sugar maple seedlings with increasing presence of conifers in a mixedwood of Southern Quebec .................................................................................. 122 Overstory and understory functional types drive mineral soil pH, C and N cycles, in mixedwood temperate plantation ........................................................................................................................ 122 Does Bioturbation Control the Chernozemic-Luvisolic Boundary in Central Saskatchewan?........... 123 Sandy soils of the Athabasca Oil Sands Region: what’s driving productivity? .................................. 123 Using historic soil survey data for spruce plantation sustainability assessments – a Nova Scotia case study.................................................................................................................................................. 124 Recreational fishing may increase greenhouse gas emissions: The earthworm connection............ 124 Tree response to organic-matter removal depends on soil properties at six Long-Term Soil Productivity (LTSP) sites in British Columbia, Canada ....................................................................... 125 Microbial communities and functioning in boreal forest soil under intensified biomass harvests .. 125 Using principal component analysis to link post-harvest soil nutrient decline to latent biogeochemical processes in an Ontario hardwood forest............................................................... 126 Poster Sessions ....................................................................................................................127 S1: Macro and Micronutrient Dynamics in Soil........................................................................ 128 Forms of phosphorus in animal manure composts .......................................................................... 129 Kinetics of phosphorus forms applied as inorganic and organic amendments during plant growth in a calcareous soil ................................................................................................................................ 129 Evaluation of phosphorus bioavailability according to the soil organic matter content – a pot experiment ........................................................................................................................................ 130 Relationship between soil organic carbon and elements under different intensity management .. 130 Soil matrix controls element cycling under alternating redox conditions ........................................ 131 Effect of raw and alkaline-stabilized biosolids on corn biomass and soil available P in three soils .. 131 Sulfur speciation in different sulfur fertilizers applied Saskatchewan soils ...................................... 132 Preliminary Assessment of Soil Quality in two contrasting Crop Rotations at the Breton Plots, Alberta............................................................................................................................................... 132 Soil mineral nitrogen released from the decomposition of green manure crops with different C/N ratios ................................................................................................................................................. 133 Soil fertility and fertilization practice influenced the transformation and loss risk of reactive N in vegetable greenhouse systems ......................................................................................................... 133 9|Page Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Seasonal soil mineral nitrogen dynamics and crop yields from a three year field based study using salmon-based silage .......................................................................................................................... 134 Phosphorus Substrate Utilization in Wheat and Canola Rhizosphere as determined by Phenotype Microarray during the Growing Season ............................................................................................ 134 Microbial Utilization of Substrates in Canola Rhizosphere ............................................................... 135 Are legume crops beneficial on soil productivity and N supply in cold eastern Canada? ................ 135 Potassium Dynamics in Sandy Soils Under Potato Crop.................................................................... 136 Soil Nutrients as Affected by Three Years of Tillage, Crop Rotation and Cover Crop Management . 136 Predicting Phosphate Adsorption by Agricultural Soils using the Component Additivity Approach and the Constant Capacitance Model ...................................................................................................... 137 Critical phosphorus concentrations and P saturation ratio levels under potato production in Atlantic Canada .............................................................................................................................................. 137 Availability of inorganic phosphorus fraction in soil amended with cow manure ............................ 138 Competitive interaction of selenium and phosphorus in wheat (Triticum aestivum L.) ................... 138 Effect of interseeding cover crops on corn biomass and nitrogen requirement............................... 139 Changes in phosphorus-fractions and phosphate-activity in ryegrass with two different phosphorus sources .............................................................................................................................................. 139 Nutrient release during litter decomposition in cold temperate forest: effects on the limitation of asymbiotic N2-fixation ....................................................................................................................... 140 Crop yield and nutrient uptake response to different rates and frequency of alkaline treated biosolid applications ....................................................................................................................................... 140 Rhizosphere phosphorus availability as affected by Al, Fe and Si content in volcanic grassland soils .......................................................................................................................................................... 141 Effects of Buckwheat as a Potato Rotation Crop on Soil and Water Quality ..................................... 141 Soils contaminated with trace metals for the production of bioenergy from biomass .................... 142 Low molecular weight organic acids reduce inorganic phosphorus adsorbed in biocarbonateextractable and Fe/Al-bound soil fractions ....................................................................................... 142 Net nitrogen mineralization enhanced with the addition of nitrogen-rich particulate organic matter .......................................................................................................................................................... 143 Short-term nitrogen dynamics in response to five rates of poultry litter with woodchip bedding .. 143 Residual readily mineralizable nitrogen responds differently to manure-type in contrasting soil textures ............................................................................................................................................. 144 The positive effects of Si on Al and Mn toxicity in sugar and silver maple ....................................... 144 Nitrogen cycling from legume and grass forages during forage phase and subsequent potato phase .......................................................................................................................................................... 145 S2: Dynamics of Pollutants in Soil .............................................................................................. 146 10 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Estimation of Volumetric Oil Content with Thermo-Time Domain Reflectometry Techniques ........ 147 Impacts of Competitive Sorption Processes on Pb Bioavailability in Urban Soils ............................. 147 Polycyclic aromatic hydrocarbons (PAHs) in sewage sludge compost in context of soil fertility ...... 148 Bioaccessible Nickel in Various Particle Sizes of House Dust from Communities Close to Nickel Mining and Smelting Operations ...................................................................................................... 148 Toxicity of silver nanoparticles in biosolid-amended soil to the earthworm Eisenia fetida ............. 149 The impact of a one-fold application of sewage sludge on the parameters of trace metals contaminated soil.............................................................................................................................. 149 The bioaccumulation of heavy metals in trees organisms during long-term field experiment on polluted soil....................................................................................................................................... 150 The impact of organic additives on the content of PAHs in soil ........................................................ 150 Rendement de zones tampons végétales aménagées pour atténuer la contamination des eaux de surface par le glyphosate et l’AMPA en champs agricoles ................................................................ 151 Small-scale horizontal variability of glyphosate and AMPA concentrations in top soil along three transects across two cultivated fields and their riparian buffer strips.............................................. 151 Determining detection limits for uptake of metals in mixtures from soils using PRSTM and DGT probes ............................................................................................................................................... 152 Arsenic dynamics in paddy rice fields in temperate climate............................................................. 152 Iron and arsenic co-precipitates: complex interfaces ....................................................................... 153 Remediation of salt and chlorinated organic contaminated fine textured soils and ground water . 153 Application of different bio-wastes as a fertilizers for degraded soil - a review ............................... 154 Using XAFS synchrotron radiation and CISED sequential extraction to identify the effect of speciation and mineral association of nickel on bioaccessibility in soil ............................................................. 154 Kinetic speciation of metal nanoparticles in presence of biosolids .................................................. 155 S3: Soil Microbiology ...................................................................................................................... 156 Root nodulation of lentil is enhanced by select phytohormone producing and H2-oxidizing bacteria .......................................................................................................................................................... 157 Effect of Plant Growth Promoting Rhizobacteria on Hyphal Growth of Arbuscular Mycorrhizal Fungi in Axenic Culture ............................................................................................................................... 157 Shifts in soil bacterial functional gene composition in response to willow planting and contamination level........................................................................................................................... 158 Methane oxidation dynamics and methanotroph community structures in peatlands across a sulphur and metal deposition gradient in Sudbury, Ontario ............................................................ 158 Value enhancement of municipal organics through the addition of effective micro-organisms...... 159 Occurrence and species richness of mycorrhizal fungi in soil under different management and use .......................................................................................................................................................... 159 11 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil hydrogenovorous bacteria – The rare biosphere in action mitigates the global emissions of atmospheric H2.................................................................................................................................. 160 Endophytic bacteria from wheat plants could be useful for Se biofortification and Gaeumannomyces graminis biocontrol ........................................................................................................................... 160 The Global Soil Biodiversity Initiative................................................................................................ 161 The role of microorganisms in a heavy metal polluted site in Mexico.............................................. 161 Does land use-intensity change microbial abundance and function on organo-mineral surfaces in grassland soils? ................................................................................................................................. 162 FLOGging a dead horse: linking decomposed organic matter carbon to nitrogen cycling in agroecosystems ................................................................................................................................. 162 Influence of environmental disturbance on microfungal communities in Israeli soils ..................... 163 Chronic N and nutrient loading in a bog: A peek into the microbial black box ................................ 163 Microbial Community Study in the Sediment of Oostanaula Creek Watershed ............................... 164 Bacterial diversity and profile characteristics of urban soils in New York City ................................. 164 PAH Bioremediation for Ecological Sustainability ............................................................................. 165 The effect of rotational and continuous grazing on soil microbiological properties: comparing the savanna and grassland biome ........................................................................................................... 165 Body size is a sensitive trait-based indicator of soil nematode community response to fertilization in rice and wheat agroecosystems ........................................................................................................ 166 Indications of shifting microbial communities associated with growing biomass crops on marginal lands in southern Ontario ................................................................................................................. 166 Soil microorganisms and enzyme activity at different levels of SOM complexity ............................ 167 Soil microbial community structure in the sacred groves of Epirus, Greece .................................... 167 Improvement of wine terroir management according to biogeochemical cycle of nitrogen in soil . 168 Soil microbial responses to wood ash addition and forest fire in managed Ontario forests ............ 168 Microbial community structures in different horizontal sub-surface flow constructed wetlands enriched with biochar as revealed by 454-pyrosequencing analysis ................................................ 169 Microbial Road Kill: How Roads Impact Bacterial Activity and Diversity .......................................... 169 Isolation and characterization of filamentous fungi from forest soil and their use for biotechnological production of immunomodulatory glycoproteins ................................................. 170 Phyto-stabilization of Sudbury mine tailings: important microorganisms in naturally colonizing plant rhizospheres ...................................................................................................................................... 170 Peatland Microbial Community Structure and Function along a Sulphur and Metal Contamination Gradient in Sudbury, Ontario ............................................................................................................ 171 S4: Organo-Mineral Interactions in Soil ..................................................................................... 172 Earthworm population dynamics in no-till corn and soybean agroecosystems in Quebec .............. 173 12 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Characterization of organic matter in density-size fractions of organically managed soils by diffuse reflectance infrared Fourier transform spectroscopy combined with NaClO oxidation ................... 173 Nanoclays from Andisols and Cambisols soils: their implication on carbon stabilization potential . 174 Effect of Organic and Chemical Fertilizers on yield and Quality Characteristics of Basil (Ocimuom basilicum L.) ...................................................................................................................................... 174 Organic matter content in different size aggregates from an Andisol .............................................. 175 Fe-C associations and soil organic matter stability in two tropical soils of contrasting parent materials ........................................................................................................................................... 175 Essential Soil Amendments for Soybean Production in Mozambique .............................................. 176 Mechanisms of organic matter accumulation and plant nutrient acquisition in permafrost soils of Northwest Territory, Canada ............................................................................................................. 176 Investigation of the relationship between total soil organic carbon (SOC) and mineralogical and physical attributes of an Amazonian Ferralsol-Podzol soil system, Brazil ......................................... 177 Physical protection of cutin and suberin in soil via organo-mineral associations ............................ 177 Evaluation of clay mineral and suberin and cutin protection of lignin in soil ................................... 178 Effect of aluminum on available carbon from an Andic and Metamorphic temperate rain forest soil .......................................................................................................................................................... 178 The effect of clay mineral composition on microbial residues in artificial soils as reflected by amino sugar content .................................................................................................................................... 179 Soil microaggregate formation as revealed by the bulk and spatial elemental composition ........... 179 A survey of Glomalin Related Soil Protein in relation to land-use and soil properties ..................... 180 Impacts of agricultural management on soil organic carbon changes in Danish mineral soils ........ 180 Soil chemicals attributes influenced by the use of spontaneous species as green manure ............. 181 Stability of soil nanoparticles as affected by natural organic matter in electrolyte solutions .......... 181 Interactions between oppositely charged surfaces in variable charge soils and the electrochemical properties at interfaces between them ............................................................................................ 182 Differential adsorption of phenolic- and nitrogenous compounds on mineral phases .................... 182 Interaction of lichen laccases and soluble phenolics with minerals: implications for humification . 183 S5: Analytical and Methodological Advances in Soil Study ................................................. 184 Prediction of soil phosphorus forms using visible near infrared reflectance spectroscopy ............. 185 Towards an understanding of precipitation dissolution mechanisms of inorganic P in calcareous soils using mineral stability diagrams ....................................................................................................... 185 Investigation of Soil Legacy Phosphorus Transformation in Long-Term Agricultural Fields Using Sequential Fractionation, P K-edge XANES and Solution P-NMR Spectroscopy ............................... 186 Identifying drought susceptible areas by using GIS: meteorological and soil properties approaches .......................................................................................................................................................... 186 13 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Comparison between mid-IR (ATR) and near-IR (DRIFT): Spectroscopy as a means of determining ten properties of soil employing partial least squares analysis .............................................................. 187 Développement et validation d’une approche d’évaluation en laboratoire de la santé globale des sols adaptée au marché agricole....................................................................................................... 187 Quantitative carbon speciation in soils using soft X-ray spectroscopy ............................................. 188 In situ quantification of canola root biomass in relation to canola growth and tolerance to climate stress in Québec ................................................................................................................................ 188 Methodological framework to predict soil hydraulic properties from a tomodensitometric analysis .......................................................................................................................................................... 189 Characterization of organo-mineral associations from tropical soil profiles using solid-state 13C NMR and thermal analysis ......................................................................................................................... 189 Portable Field Mass Spectrometer for Measurement of Gases in Soils ............................................ 190 Freeze-thaw cycle impact on macropore flow and nutrient transport through soil monoliths ....... 190 Advanced analytical techniques for the characterization of soil organic matter composition and biogeochemistry................................................................................................................................ 191 Comparisons of gap filling methods on nitrous oxide fluxes from a corn-soybean-wheat rotation over 6 years ....................................................................................................................................... 191 Microbial amino sugars of some Canadian agricultural soils ............................................................ 192 S6: Agricultural Greenhouse Gas Emissions ........................................................................... 193 Using proximal soil sensing to optimize assessment of agricultural greenhouse gas emission ....... 194 N2O emissions as affected by fertilization and water table management in south-western Ontario .......................................................................................................................................................... 194 Glycerol from the biodiesel industry: Can it reduce ammonia volatilization and nitrate leaching in soil treated with liquid manure? ....................................................................................................... 195 Soil-Atmosphere Exchange of Carbon Dioxide, Methane and Nitrous Oxide in Shelterbelts Compared with Adjacent Crop Fields ................................................................................................................. 195 Beneficial Management Practices for Greenhouse Gas Mitigation from Agroecosystems .............. 196 Factors Determining Low and High Emissions of Greenhouse Gases from Canadian Beef Cow-Calf Farms ................................................................................................................................................. 196 Changes in snow cover alter nitrogen cycling and gaseous emissions in agricultural soils .............. 197 Method and timing effect of field applied anaerobically digested and raw dairy manure on soil nitrous oxide emissions from corn production ................................................................................. 197 Associating the potential of organic amendments for soil N2O emissions to their chemical characteristics ................................................................................................................................... 198 Measuring and modelling the long-term impact of crop management on soil C sequestration in the semi-arid Canadian prairies .............................................................................................................. 198 Abundance of Ammonia-oxidizing Archaea and Bacteria in Woody Perennial Cropping Systems ... 199 14 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The role of water-table, soil depth, and nitrogen fertilizer on the interaction of soil microbial biomass and gas emission ................................................................................................................. 199 Green management of sugarcane and its effects on nitrous oxide emissions in Northeastern Brazil .......................................................................................................................................................... 200 Overall evaluation of solid waste composting and agricultural recycling: a methodological framework proposal .......................................................................................................................... 200 Development of a simplified and economical technology to measure N2O and CH4 emissions from livestock buildings ............................................................................................................................. 201 Comparison of Methods for Predicting Pore Space Indices in Corn-Soybean Field ......................... 201 Evaluation of the effect of depth and distance of subsurface drainage systems on methane gas emissions........................................................................................................................................... 202 The Effect of Nitrogen Fixation on Direct and Indirect Nitrous Oxide (N2O) Emissions in Dairy Crop Rotations ........................................................................................................................................... 202 Grazing influences C and N storage in the Northern Great Plains .................................................... 203 S7: Chemical and Biological Controls on Organic P Cycling in Terrestrial and Aquatic Environments .................................................................................................................................... 204 The influence of phosphorus fertilization on grassland soil phosphorus forms: A 31P-NMR study .. 205 An investigation of the origins of inositol hexakisphosphate stereoisomers in crested wheatgrass pasture soils ...................................................................................................................................... 205 Impact of long-term application of composted organic residue on soil organic and inorganic phosphorus dynamics ....................................................................................................................... 206 Short-term transport and transformation of phosphorus species from a poultry manure amended soil during leaching ........................................................................................................................... 206 Phosphorus transformations and mobility in the rhizosphere of phytase-exuding plants following a single cultivation cycle ...................................................................................................................... 207 C:P stoichiometry in Canadian peatlands and forest litter ............................................................... 207 P pools and microorganisms response to a 5-year P fertilization pot trial for wheat only in a ricewheat rotation in paddy soils in the Taihu Lake Region of southern China ...................................... 208 Long-term phosphorus fertilization and tillage impact soil phosphorus transformation and distribution........................................................................................................................................ 208 S8: Microbial Provision of Essential Services across Managed and Natural Ecosystems .............................................................................................................................................................. 209 Diversity and abundance of rhizobacteria encoding phosphatase gen from Chilean extreme environments .................................................................................................................................... 210 Thermodynamic profiles and carbon use efficiency of soil microbial communities in contrasting agroecosytems .................................................................................................................................. 210 The Use of a Conceptual Model to Determine Biological Soil Crusts as the First Terrestrial Ecosystem: Their Role in Embryophyte Land Colonization .................................................................................. 211 15 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 13 C cellulose assimilation in different transplanted Chernozems after 21 years of common management and climatic conditions ............................................................................................... 211 Microbial communities and nitrogen cycle in reclaimed oil-sand soils ............................................ 212 Abundance and gene expression of bacterial and archaeal ammonia monoxygenase (amoA) in a monoculture versus a diverse crop rotation, under conventional and no-till management ............ 212 Fungal Diversity Associated with Pulses and its Influence on the Subsequent Wheat Crop in a 2-Year Study ................................................................................................................................................. 213 Microbial Community Structure and Activity after Long-term use of Dairy Manure and Fertilizer Reflects Soil Properties and Impacts Soil N Transformations............................................................ 213 Evaluating the Efficacy of the Nitrification Inhibition Assay Method using 3, 5-dimethylpyrazole in Soils that Differ in Texture and Water Content ................................................................................. 214 Growth of Timothy root and associated arbuscular mycorrhizae as affected by phosphorus fertilization in North Québec ............................................................................................................ 214 S9: Soil Science Education and Outreach ................................................................................ 215 Developing an on-line nutrient management planner-training program in Atlantic Canada ........... 216 Web-based Educational Tool for Forest Floor Description and Humus Form Classification ............. 216 EasyGrapher v4.6: Software for Data Visualization and Statistical Evaluation of the DSSAT v4.x model and the CANB v4.0 Model ................................................................................................................. 217 Investigating Student Perceptions of Academic and Professional Learning Experiences in a FieldBased Course ..................................................................................................................................... 217 S11: Wetland Soils in a Changing Climate ................................................................................ 218 Examining the fate of carbon among wetlands reclamation trials in Fort McMurray, Alberta ........ 219 Detecting soil drainage and compaction issues by ground penetrating radar in Histosols .............. 219 Soil organic carbon in riparian ecosystems and the potential of C reservoirs in a context of environmental sustainability ............................................................................................................. 220 Impact of Short Rotation Willow on Prairie Wetland Soil Hydrology and Salinity ............................ 220 Variability of peat soil characteristics in boreo-nemoral environment (Latvia) ................................ 221 Nutrient dynamics along drainage ditches under recent, medium and long-term drainage in the Black soil zone of southeastern Saskatchewan ................................................................................. 221 S12: Proximal Soil Sensing ........................................................................................................... 222 Impacts of subirrigation and low water potential on soil salinity and its effects on cranberry development ..................................................................................................................................... 223 Comparing logistic model trees and multinomial logistic regression for the prediction of soil development in BC ............................................................................................................................ 223 A new model to predict soil pH at depths in agricultural fields ........................................................ 224 S13: Spatial and Temporal Dynamics of Soil Processes and their Interactions at Multiple Scales to Study Complex Soil Systems ..................................................................... 225 16 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The Relationship between Ion Exchange Membrane (PRS Probe) Measurements and Extractable Nutrient Concentrations ................................................................................................................... 226 Interactions between the microbial processes and nutrient transformations in beach sediments under dynamic flow regimes............................................................................................................. 226 Soil Phosphorus Distribution under Two Contrasting Grasslands (2 and 10 yrs old) ........................ 227 Effect of long-term tillage regimes on topsoil pore network dynamics and field saturated hydraulic conductivity....................................................................................................................................... 227 Interaction of nitrogen fertilizer application, crop rotation, and tillage system on long-term soil carbon and nitrogen dynamics ......................................................................................................... 228 Does Row Width and Harvest Date Influence Sugarbeet (Beta vulgaris L.) Nitrogen Requirements? .......................................................................................................................................................... 228 Nutrients in snowmelt and rainfall-generated runoff from the clay soils of the Red River Valley, Manitoba, Canada ............................................................................................................................. 229 Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic ........ 229 Evaluating the Impact of the Spatial Distribution of Land Management Practices on Water Erosion .......................................................................................................................................................... 230 Uncertainty and sensitivity analysis of the DSSAT model: soil water, management and weather parameters ........................................................................................................................................ 230 Coarse Woody Debris Increases Soil Respiration Rates and Microbial Function but Not soil Enzyme Activity in Cover Soils for Oil Sands Reclamation .............................................................................. 231 Effects of input management, crop diversity, environmental covariates and terrain attributes on crop yield in the semi-arid Canadian Prairie ..................................................................................... 231 Testing effectiveness of the Environmental Policy Integrated Climate Model on Predicting Wheat, Barley, and Canola Yield in the Canadian Prairie .............................................................................. 232 Interaction or a common entry: Soil organic carbon in soil water content measurement ............... 232 Water footprint assessment of crop production in Canada using a Canadian water budget model 233 Banded vegetation effects on soil water storage and temperature in Jornada Basin, New Mexico 233 Delineation of Fe-oxides Pedofeatures in Thin Section of Hydromorphic Soils ................................ 234 Scenario Analysis of Canadian Farming System to Residual Soil N using a CANB v4.0 model .......... 234 Modeling of Soil Water and Salt Dynamics with Shallow Water Table and Its Effects on Root Water Uptake and Heihe Arid Wetland, Gansu, China ................................................................................ 235 S14: General Soil Science ............................................................................................................. 236 Corn yield and quality as a function of nitrogen fertilization and soil texture ................................. 237 Predicting ammonia volatilization from swine slurry application using DNDC: Model development .......................................................................................................................................................... 237 Supervision of Nutrition, From Soil to Kitchen ................................................................................. 238 Excess more than deficiency of boron affects the physiological features in highbush blueberry .... 238 17 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of Tillage, Cover Crop and Corn-Soybean Rotation on Soil Pore Space Indices ...................... 239 Evolution of soil hydraulic properties during repeated cycles of drainage and recharge ................. 239 Strategies to improve the phosphorus uptake efficiency of Al-tolerant wheat cultivars grown in volcanic soils ..................................................................................................................................... 240 The relationship between compaction and structural properties of Québec soils .......................... 240 S15: Biochar in Agriculture and Environment/ Le Biochar en Agriculture et en Environnement ................................................................................................................................. 241 Effet de l’ajout de biochar sur la symbiose tripartite Ensifer meliloti-Rhizophagus irregularis-Luzerne (Medicago sativa L.) .......................................................................................................................... 242 Reconstructed topsoil using biochar or oxidized lignite for site reclamation ................................... 242 Comparing Black Carbon Measurements from Thermal Analysis and National-Scale MIR Calibrations in Minesoils ....................................................................................................................................... 243 Effects of biochars soil application on nitrogen and phosphorus availabilities ................................ 243 Evaluating the effect of biochar application on some biological quality and properties of vermicompost ................................................................................................................................... 244 Amendments to increase maize (Zea maize) yield in an alfisol in Sri Lanka ..................................... 244 Biochar Alters Activity of Extracellular Enzyme and Abundance of Bacterial and Fungal Populations in Subtropical Mangroves ................................................................................................................. 245 Biochar reduces loss of organic amendments in tropical field conditions ....................................... 245 S17: Soils of Natural, Managed and Intensive Forest Systems/ Les Sols de Systems Forestiers Naturels, Aménagés et Intensifs .............................................................................. 246 Mechanical site preparation treatment influences soil microbial community structure and function: Identification of multifunctional molecular stress indicators of sylvicultural practices ................... 247 Caractérisation des chemins (écoulements) préférentiels superficiels sur l’efficacité du piégeage des sediments d’une bande riveraine à l’aide de l’imagerie LIDAR et de la modélisation ...................... 247 Soil temperature changes can be a reliable indicator of global climate change under hot and desert ecosystems ........................................................................................................................................ 248 Baseline Assessment of Soil Chemical Properties and Nutrients in Ituri Forest, Democratic Republic of Congo ............................................................................................................................................ 248 Carbon losses from deforestation in Russia during 1990-2012 ........................................................ 249 Corresponding Authors ........................................................................................................250 Keynote Speakers ............................................................................................................................ 251 Oral Sessions .................................................................................................................................... 252 Index ......................................................................................................................................273 18 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Keynote Sessions 19 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 PLENARY SPEAKER SESSION 1 Changing Concepts of Organo-Mineral Interactions in Soils: Impacts on Soil Properties and Sustainable Development Thermodynamics and kinetics of plant iron acquisition Stephan M. Kraemer John Duxbury Interactions between organic compounds and minerals in soil has been studied from the perspectives of soil genesis, nutrient availability for plants, organic matter decomposition/stabilization and soil structure and porosity, all factors that affect crop growth and productivity. Over time the classic and rather static view of soil humic substances interacting with clay mineral surfaces and inorganic ions has evolved to include a much wider range of organic compounds and mineral phases, and dynamic interactions between soil fauna, microbes, plants and soil. Today, we have the capacity to study organo-mineral interactions almost at the atomic scale. The existence, and validity of the concept, of humic substances has been challenged and biochar has been proposed as both the stable form of organic matter in soils and a strong promoter of soil fertility. The rhizosphere has become recognized as a key zone for change during plant growth, including alteration of soil pH and redox potential in addition to exudation of organic phyto-metallophores. Yet, bulk soil properties remain important. The presentation will focus on discussion of 1) how can our new knowledge and new approaches to studying organo-mineral interactions be used to help meet the multiple challenges of sustainable development in an era of climate change?, 2) how can crop mineral nutrient quality be improved while also increasing productivity?, and 3) what can be applied in tropical developing countries where most of the future growth in population will occur. 20 | P a g e University of Vienna. Environmental Geochemistry Biological nutrient acquisition processes involve highly regulated biochemical responses to complex soil physical, chemical and microbiological properties and mechanisms. A key strategy of nutrient acquisition is the exudation of reactants that interact with the target nutrient directly or that change the geochemical environment in the soil in order to modify equilibrium states and rates of reactions limiting nutrient bioavailability. In order to elucidate or modify such acquisition processes, it is necessary to understand the soil chemistry of the target nutrient and of the biogenic reactants that are exuded. This includes key processes that limit nutrient availability and coupled reaction networks. As an example plant iron acquisition strategies are discussed. Iron deficiency symptoms are typically observed in plants growing on aerated calcareous soils, where the availability of iron is severely limited by the low solubility and slow dissolution rates of iron oxides, oxohydroxides or hydroxide phases. Iron efficient plants accelerate the mobilization of iron by rhizosphere acidification, exudation of ligands including phytosiderophores and exudation of reductants. These plant responses are capable of inducing proton promoted, ligand controlled and reductive dissolution mechanism. All of these mechanisms are at least partially inhibited by coupled reactions. Synergistic effects between different mobilization mechanisms that have the potential to overcome these limitations to some degree will be discussed. Also, the reactants exuded by the plant roots in order to promote these mobilization processes undergo various sider reactions that decrease their efficiency. A conceptual model will be presented that integrates soil chemical properties, key reactions and coupled reaction networks influencing time-dependence and intensity of plant iron uptake. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 2 SESSION 3 The Contributions of Heritable Variation, Soil Chemistry, and Meteorological Conditions in Accumulation of Cd by Glycine max in Ontario Soil microorganisms – architects and actors of biogeochemical interfaces Beverley Hale School of Environmental Sciences, University of Guelph. Doreen Babin1, Guo-Chun Ding2, Cordula Vogel3, Geertje J. Pronk3,4, Katja Heister3, Ingrid KögelKnabner3,4, Michael Schloter5, Kornelia Smalla1* 1 Julius Kühn-Institut, Epidemiology and Pathogen Diagnostics College of Resources and Environmental Sciences, China Agricultural University 3 Lehrstuhl für Bodenkunde, Technische Universität München 4 Institute for Advanced Study, Technische Universität München 5 Research Unit for Environmental Genomics, German Research Center for Environmental Health 2 There is variation in accumulation of trace elements by plants from soils, due to plant physiological characteristics (such as hyperaccumulation), soil chemistry, metal and metalloid speciation, and bulk transport through the soils. Cadmium is an interesting element for study, as it is very mobile in the soil-plant continuum, has heritable variation in accumulation by a number of agronomically important crops, and is not very phytotoxic yet is of concern for human health due to its long half-life in mammals. Foods from oilseeds and grains are a significant dietary source of Cd, present in agricultural soils as a result of geogenic sources, agricultural practices, and deposition from the atmosphere. Predicting the concentration of Cd that would be expected in the agricultural product from a particular soil concentration of Cd would be useful to agricultural producers. However, it is recognized that this approach is currently limited by the largely unquantified, additional influence of plant specific factors and meteorological effects on transport of Cd from bulk soil into soil solution, and finally into the seeds of the crops. Surveys of paired soils and soybeans across Ontario, coupled with meteorological data, define the contribution of evapotranspiratory demand and bioavailable Cd in soil, to Cd accumulation in the plants. Companion laboratory work identifies the potential for different varieties of soybean (high- and low-seed Cd accumulators) to enhance the bioavailability of Cd through root processes such as acidification of the root environment, or greater mass movement of soil solution through the plant. This information can be integrated into a Best Management Practice suitable for use by both agricultural producers and regulators, to understand the science bases and the options for mitigation, of Cd accumulation in field crops. 21 | P a g e Soil microorganisms perform many processes essential for the ecosystem such as nutrient cycling, pollutant degradation, regulation of plant growth, plant health and soil structure. They reside in a highly complex habitat characterized by the proximity of heterogeneous soil components resulting in the formation of large biogeochemical interfaces (BGIs). The presence of various micro-sites and –gradients goes along with a tremendous microbial diversity. The advent of cultivation-independent techniques (e.g. denaturant gradient gel electrophoresis, pyrosequencing of 16S rRNA amplicons) in microbial ecology allows exploring this diversity. Minerals and charcoal might be due to their abundance in soil and high surface activity important factors for microorganisms and BGIs. In order to elucidate the potential role of minerals and charcoal on the formation and functionality of microbial communities at BGIs, results from artificial soil experiments conducted under controlled conditions will be presented. Artificial soils received the same inoculum from a natural soil and the same nutrient input and differed only in type of clay mineral (illite, montmorillonite), metal oxide (ferrihydrite, aluminum hydroxide) and the presence of charcoal. A first short-term incubation experiment aimed at studying the initial formation of microbial communities. Charcoal was identified as early (90 days) shaping factor for Bacteria. However, after more than one year incubation, metal oxides were the main driver of the soil microbiota proving the ongoing development of BGIs. A second artificial soil experiment lasting for more than two years showed that microbial communities at BGIs long-term matured as a function of the soil composition differed in their quantitative and qualitative response to organic soil amendments with clay minerals being the main driver. Further methods beyond the 16S rRNA gene level will be discussed during the presentation that might provide additional information on functionality and spatial distribution of soil bacteria. Examples will be given how this knowledge can be applied. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 4 SESSION 5 Organo-mineral associations at different levels of soil aggregate hierarchy: What do we get from physical fractionation? Advances in the characterization of soil organic matter and speciation of major nutrient elements by the application of complementary mass spectrometric and synchrotron-based X-ray spectroscopic methods Rota Wagai National Institute of Agro-Environmental Science, C & Nutrient cycling division, Japan Organic matter (OM) in soil is subject to both microbial transformation and interaction with soil minerals, which presumably leads to the formation of soil aggregate. Due to the variations in mineral and OM compositions as well as the nature of the interaction between the two, organo-mineral particles or aggregates have a range of size and density. In fact, physical fractionation studies have been useful to study organo-mineral interaction and the factors controlling the storage and turnover of soil OM. However, it remains unclear how the findings from fractionation studies are related to the concept of aggregate hierarchy (e.g., larger aggregates are maintained by transient binding agents while smaller ones are held together by more persistent binders). Here we present three studies that use the fractionation approach to examine how short- and long-term soil OM dynamics are linked to the hierarchy concept using Japanese volcanic-ash soils that is known for strong aggregation and OM stabilization capacity. First, we demonstrated that the isolation of low-density fraction, a readily accessible OM outside of aggregates, was necessary to examine the factors controlling decomposition temperature sensitivity. Second, using sequential density fractionation, we isolated soil aggregates that are resistant to mechanical shaking and showed density-dependent changes in the chemistry of OM (δ13C, δ 15N, d14C as well as C:N ratio) and that of mineral phases (organically complexed metals and short-rangeordered minerals). Third, we found the particle size dependent changes in organo-mineral chemistry in the same soil only after achieving maximum dispersion of these aggregates by sodium saturation followed by sonication. Clay-sized particles after the dispersion, however, still showed aggregated features by SEM and TEM. We will discuss possible factors controlling OM stabilization in these fractions and the presumed relationship between the fractions obtained from different levels of aggregate hierarchy (sonicationresistant particles vs. shaking-resistant aggregates). 22 | P a g e Peter Leinweber1 & Adam Gillespie2 1 Soil Science, University of Rostock/Germany Canadian Light Source, Saskatoon/Canada 2 The characterization of bulk, non-extracted soil organic matter (SOM) and organic-mineral particles and reactive surfaces is a challenge that stimulates the development and refinement of analytical techniques. Since often the target molecules or compound classes that have been altered by agronomic or environmental impact are unknown, so called „non-targeted“ methods are applied for a first screening before individual compounds or compound classes are determined by more specific techniques. Analytical pyrolysis methods such as pyrolysis-field ionization mass spectrometry (Py-FIMS) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) have been widely applied in this research but recently the spectral resolution has been further improved to enable high-resolution measurements and a better spectral interpretation than before. Fourier-transformation ion cyclotron resonance mass spectrometry (FT-ICRMS) is another complementary technique that becomes more popular in soil research because of its ultrahigh resolution yielding the elemental composition and molecular formulae. Disadvantages of these methods can be partially overcome by the application of complementary synchrotron-based techniques such as X-ray absorption near-edge fine structure (XANES) spectroscopy, most recently in combination with elemental mapping and with a µ-focused beam. The latter techniques enable the speciation at high spatial resolution and observed where at the organic-mineral surfaces key chemical reactions take place. The value of applying these innovative techniques in conjunction will be exemplified by (1) the impact of heat on the SOM composition, (2) the characterization of mineralorganic matter associations in soil clay fractions and (3) the structure and functioning of biological soil crusts. Particular emphasis is payed to the speciation of the elements carbon, nitrogen and phosphorus. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 6 SESSION 7 Nitrogen Fertilization and Soil N2O Emissions Role of iron oxides in controlling organic P cycling in soil Philippe Rochette Luisella Celi Agriculture and Agri-Food Canada Università di Torino, DISAFA-Soil Biogeochemistry Nitrogen fertilization of agricultural crops is the more important contributor to soil N2O emissions. However, the fraction of applied N that is lost as N2O, or emission factor (EF), is highly variable. This variability is the result of factors related to the fertilization itself (fertilizer type, application mode, etc.) but also because of interactions with farming practices and soil environmental conditions, themselves influenced by soil properties, weather and crop growth. The objective of my presentation is to review the literature for summarizing our understanding of the impact of management practices on fertilizer-induced (emission factor, EF) N2O emissions. Several issues will be reviewed such as how the EF is impacted by 1) N application rate, 2) climate and selected soil properties, 3) fertilizer type (NH4- or NO3-based, specific commercial formulations, urease and nitrification inhibitors, controlled-release forms), 4) N placement (banding, depth), 5) timing of N application (split, spring vs fall), 6) presence of organic forms (manure, crop residues, etc.), and 7) other issues such as the use of biochars. In conclusion, the suitability of the global database for exploring options for mitigating soil N2O emissions will be discussed. 23 | P a g e Organic P cycling in soil is strongly controlled by abiotic processes, with a selective stabilization of inositol phosphates with respect to the other organic P species. This is linked to the high affinity of inositol phosphates for iron oxide surfaces that hamper their degradation and control their fate in soil. Thus the proportion of different organic P species and the retention by the solid phase is governed by Fe oxide characteristics, in turn controlled by pedoclimatic factors. This presentation is aimed to review the factors that control adsorption thermodynamics and kinetics of inositol phosphates on iron oxides differing for their mineral properties, such as the degree of crystallinity, the proportion of reactive sites for adsorption on the total area, and the distances between contiguous hydroxyls. Computational studies will show the optimal arrangement of the myo-inositolhexakisphosphate molecule on the mineral surface. Furthermore we will evaluate how the strength and extent of inositol phosphate binding to the different Fe oxides affect phytase activity and extractability determined by different agents. Finally NaOH-EDTA extractability, which is a crucial step of organic P characterization, will be considered. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 9 SESSION 11 Soil Science Education with K-12 students in Canada Ecosystem-scale methane fluxes in Canadian wetlands Doug Hayhoe Elyn Humphreys Tyndale University College Carleton University Soil scientists who visit school classrooms, or interact with K-12 students or their teachers in other venues, may benefit from knowing what their provincial curriculum says, what a typical classroom teacher knows, and what resources and programs are available regarding soil. Many provinces have a soil science unit at the Grade 2-4 level in their curriculum. In all provincial curricula, we find soil science concepts in units on living things, plants, and ecosystems, at elementary, intermediate, and senior levels. Moreover, hands-on soil programs can be effectively used to meet skills and attitudes expectations in many areas of the curriculum, from Kindergarten up. In this talk, we will look at science curriculum across the country in some detail, highlighting these opportunities. What use is it having soil science in the curriculum, however, if the teachers primarily responsible for student learning don’t understand the key concepts? With this in mind, we will briefly consider research results on the understanding of elementary teachers about soil, using a 25-item soil questionnaire we have developed and compare it with similar results elsewhere. We will also look at gains in teacher understanding, after learning more about soil science. This may encourage those involved with soil education outreach to teachers. Excellent resources for teaching hands-on soil science to children will be noted. Soil science through stories is another approach for reaching primary students, with the focus on literacy today. At the high school level, we have the national “Soil 4 Youth” program, supported by the CSSS. It supports the integration of soil science into school programs across Canada. Other high school resources are also available. Although there is no shortage of resources, however, it always requires additional energy and creativity to engage students in hands-on, fun activities with soil, both in the classroom and in the field. A number of long-term records of ecosystem scale carbon dioxide (CO2) exchange between wetlands and the atmosphere have been collected over the past two decades using the eddy covariance technique. Despite considerable inter-annual variability, many of the longterm peatland sites are overall, consistent sinks for CO2. However, these wetland ecosystems are also all sources of methane. With recent advances in methane analyzers suitable for eddy covariance measurements, multi-year ecosystem scale records are now being built. The multi-year records from a number of Canadian wetlands will be presented. The weather and peatland characteristics that are well known to relate to small chamber fluxes will be contrasted to the relationships (and lack of relationships) that are found when spatially variable and temporally sporadic methane emissions are integrated at the ecosystem scale. 24 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 12 SESSION 13 Proximal multi sensor system for measuring soil condition Scales and scaling in soils: Soilscope for soilscape Raphael Viscarra Rossel Yakov Pachepsky Commonwealth Scientific and Industrial Research Organization (CSIRO) In this presentation I will discuss the importance of soil measurement and review proximal soil sensing (PSS): the technologies that are currently available and their use for measuring soil properties. I will discuss the sampling dilemma and using the range of frequencies in the electromagnetic spectrum as a framework, describing technologies that can be used for PSS, including electrochemical and mechanical sensors, telemetry, geographic positioning and elevation, multisensor platforms, and core measuring and down borehole sensors. Because soil properties can be measured with different proximal soil sensors examples will be given of the alternative techniques that are available for measuring soil properties. The developmental stage of technologies for PSS will be reported and the current approximate cost of commercial sensors. The presentation will focus on the development of PSS over the past 30 years, on its current state and the future. I will report results of research to develop a multisensor system to measure soil organic carbon stocks. Results will show that the multi-sensor system can be used to derive accurate estimates of soil carbon stocks, which might then be used for baselining and with appropriate designs also monitoring. 25 | P a g e Beltsville, Agricultural Research Center The objective of this presentation is to provoke discussion on status of scale concepts and techniques in soil systems analyses that operate with data collected at different scales and have to overcome the scale mismatch among components of knowledge acquisition, packaging and use for societal needs. Three major definitions of scale – via hierarchies, measurement metrics, and similitude are discussed, and differences in scaling under each of the definitions are reviewed. Advantages and limitations of traditional scaling methods such as dimensional analysis and inspectional analysis are acknowledged. The power law scaling is reviewed with regard to mechanisms and models leading to it. Support change techniques via aggregation and weighted interpolation including wavelet decomposition and data assimilation are summarized. The fast growing field of scale change in spatio-temporal information is represented with scaling using empirical orthogonal functions and cumulative distribution matching. Special cases of scaling based on processes and phenomena, such as fragmentation, temporal stability, and Buckingham flow, are briefly summarized. The importance of scaling variability metrics and parameters of flux models is underscored. The role of scaling increases in the era of ‘big data’. The arsenal of scaling methods is expected to grow as it performs the important function of obtaining data we need from data we have. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 SESSION 15 SESSION 17 Historic Barriers to Biochar Utilization: Is there a way to avoid these same hurdles? Restoring organic matter processes in reconstructed soils Kurt Spokas Sylvie A. Quideau United States Department of Agriculture (USDA) – Agricultural Research Service Biochar (a form of black carbon) has been recently heralded as an amendment to revitalize wornout/weathered soils, increase soil C sequestration, enhance agronomic productivity, and enter into future carbon trading markets. Research since the dawn of modern science has demonstrated that biochar has variable properties, which greatly impacts predicted outcomes. This presentation will summarize what is known from a historical and recent perspective and then look forward to see if the past provides pathways for the future direction. With population expansion and finite area of tillable earth, improving nonproductive soils with biochar has been extolled as a solution to these issues and an agent of improving agriculture’s environmental stewardship. But how are we going to overcome the historic hurdles to its use? University of Alberta, Department of Renewable Resources Reclamation efforts following drastic land disturbance such as open-pit mining often involve reconstructing soils using materials that are salvaged prior to the start of mining. Re-establishing essential functions in reconstructed soils, such as efficient biogeochemical processes, is the basis of successful reclamation. A key component deserving special attention is the quality of the organic component (topsoil) used to cap reconstructed soils, and in particular its ability to supply nutrients to soil biota and plants. Clear linkages exist between soil organic matter, microbial communities and nutrient availability in native forests. However, these links can be disrupted in postmining soils. In the Athabasca Oil Sands Region of Northeastern Alberta, many attributes of reconstructed novel soils differ from native forested soils of the area, calling into question the usefulness of using a quality index based on criteria measured in undisturbed or less drastically disturbed soils. Instead, the following avenues are recommended to quantify organic matter processes in reconstructed soils: 1. Quantifying organic matter criteria along chronosequences of reclaimed sites to more accurately assess their rate of change in reconstructed soils, and help estimate the recovery trajectory of organic matter processes, 2. Using indicators of soil organic matter functioning, such as substrate induced respiration profiles, which may be more useful than structural attributes where no relevant reference values are available, and 3. Following elemental fluxes quantitatively in novel ecosystems labeling. 26 | P a g e using stable isotope Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Oral Sessions Abstracts are displayed by session order 27 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S1: Macro and Micronutrient Dynamics in Soil 28 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil properties and not inputs control the carbon, nitrogen, phosphorus relationships in cropped soils Emmanual Frossard1, N. Buchmann2, E.K. Bünemann1, D. Kiba3, F. Lompo3, A. Oberson1, F. Tamburini1, O.Y.A Traoré3 1 Institute of Agricultural Sciences, Group of Plant Nutrition Institute of Agricultural Sciences, Group of Grassland Sciences 3 Institut de l’Environnement et de Recherches Agricoles (INERA) 2 Stoichiometric approaches have been applied to understand the relationships between soil organic matter dynamics and biological nutrient transformations. However, most studies focused on unmanaged systems, whereas the impact of management on the C, N and P relationships in agricultural soils has been neglected. The aim of this work was to assess how inputs would affect the C:N:P ratios of soil organic matter and microbial biomass in cropped soils. Thus, we analyzed the results of three long-term experiments: the Saria soil fertility trial (Burkina Faso), the rotation/stubble management/soil preparation trial in Wagga Wagga (Australia) and the DOK cropping system trial (Switzerland). Increasing C, N and P inputs led to increased nutrient contents in soil pools in each trial. In contrast, different inputs affected the soil C:N:P ratios in two ways. In Saria, a positive correlation was found between the N:P ratio of the inputs and the N:P ratio of the microbial biomass, while the elemental composition of the inputs had no effect on soil organic matter composition. At Wagga Wagga, the C:P and N:P ratios of the inputs were positively correlated to the C:P and N:P ratios in soil organic matter, but had no impact on the composition of the microbial biomass. The DOK gave intermediate results. These responses were explained by differences in soil properties. In Saria, the soil is dominated by quartz, has a coarse texture, a fragile structure and a low nutrient content. There the microorganisms must feed on the inputs and organic matter is not protected against mineralization. On the opposite, in Wagga Wagga the soil contains also illite and hematite, it is richer in clay and nutrients, and has a more stable structure. In this soil, microorganisms can feed on soil nutrients and organic matter is better protected from mineralization. 29 | P a g e Following the Fate of Different Sulfur Fertilizers in Prairie Soils Jeff Schoenau, Tom King, Gourango Kar, Hasan Ahmed, Derek Peak University of Saskatchewan, Soil Science The form of sulfur fertilizer applied to soil can profoundly influence important attributes such as plant availability and mobility. Field studies were conducted in 2013 and 2014 in Saskatchewan in which different forms of sulfur fertilizer (ammonium sulfate, potassium sulfate, calcium sulfate, ammonium thiosulfate and elemental S) were applied in the seed-row of three crops (canola, wheat, peas) grown on three different soils: Brown Chernozem, Gray-Black Chernozem, Gray Luvisol. Samples of soil were collected from the seed-row at one, four and eight weeks after seeding and 0.01M CaCl2 extractable sulfate was measured in the samples. Supply rates of sulfate were assessed over eight weeks, in-situ using PRS probes. XANES spectroscopy was used to reveal sulfur forms present in the soil samples from selected treatments. Soluble sulfate forms produced the highest concentrations and supply rates of sulfate in the seed-row initially, with calcium sulfate maintaining the greatest concentration in the band over time due to its slightly soluble nature. Elemental S had the lowest sulfate content and supply rate in the seed-row throughout the season as a result of incomplete oxidation to sulfate. Thiosulfate converted rapidly to sulfate in the soil. The largest depletion of sulfate by plant uptake took place in the day 7 to day 28 time interval. Using XANES spectroscopy, thiols and ester sulfates were identified as S compounds formed in the seed-row of amended soils, presumably as a result of microbial immobilization. There was also evidence of oxidation of reduced sulfur forms. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A field microcosm study to investigate phosphorus release from Manitoba soils under prolonged flooding Soil Phosphatase and Phytase Activities in Canola and Wheat Rhizospheres during the Growing Season Kumudu Jayarathne1, Darshani Kumaragamage1, Don Flaten2, Srimathie Indraratne1, Doug Goltz3 Marcela González and Carlos Monreal* 1 University of Winnipeg, Environmental Studies and Sciences 2 University of Manitoba, Soil Science 3 University of Manitoba, Chemistry Reduced conditions resulting from flooding often lead to an enhanced release of phosphorus (P) from agricultural soils and natural wetlands to overlying water. In a field microcosm study using soils collected from flood-prone areas of Manitoba, we compared the magnitude and patterns of P released from 12 soils under flooded, reduced conditions. Soil texture varied from Sandy Loam to Heavy Clay and initial soil pH was varied slightly acidic to alkaline range. These soils were subjected to simulated flooding for period of eight weeks and soil redox potential (Eh), soil pH and concentrations of dissolved reactive phosphorus (DRP) in floodwater and pore water were measured weekly. Soil redox potential values varied between +490 and +270 mV initially and dropped to +70 to 67mV with flooding. Soil pH became to neutral range in almost all the soils with flooding. Initial DRP concentration in floodwater varied between 0.05-1.00 mg L-1 and increased up to 0.1-6.7 mg L-1. The pore water DRP concentration ranged from 0.09-7.2 mg L-1 and increased up to 0.6-15.5 mg L-1. Floodwater DRP concentration significantly increased in six soils whereas pore water DRP concentration significantly increased in seven soils. Some soils showed a decline in floodwater DRP concentration after 42 days of flooding. Results suggest that flooded reduced conditions enhance the phosphorus release to overlying water in most soils, and quick drainage of such soils before anaerobic conditions develop would be effective in reducing redox-induced P release to floodwater. 30 | P a g e Agriculture and Agri-Food Canada Little is known about the dynamic of soil phosphatase and phytase activities during crop growth stages. Plants and soil microorganisms have responsive mechanisms to obtain, mineralize and recycle soil phosphorus (P) to preserve cell homeostasis. Of the total soil P, organic P (Po) is the most abundant fraction, and phytic acid is the most abundant Po compound. Accordingly, Po is mineralized into soil solutions by phosphatases and phytase, respectively. A greenhouse study was conducted to examine weekly the acid phosphatase and phytase activities in the rhizosphere of a Melanic Brunisol planted to canola (Brassica napus) and wheat (Triticum aestivum). Four replicated treatments were established: soil alone; soil + crop (unfertilized); soil + crop + fertilizer-N; soil + crop + fertilizer-N-P. Overall, soil acid phosphatase activity was higher in wheat than in canola rhizosphere, and in planted versus unplanted soil. In both crop rhizospheres, the highest phosphatase activity occurred during tillering and heading in the N+P treatment. The lowest enzyme activity occurred in the soil alone and the unfertilized crops. Information on phosphatase and phytase activities contributes to enhance our knowledge of temporal soil P cycling in the rhizosphere of wheat and canola. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The effects of cover crops on phosphorus cycling in agricultural soils of California Gabriel Maltais-Landry1, Eric Brennan2, Emmanuel Frossard3, Kate Scow4, Peter Vitousek5 Tillage Practice and Phosphorus Fertilization Effects on the Distribution and Morphology of Corn Root Haixiao Li1, Noura Ziadi2, Leon-Étienne Parent3, Christian Morel4, Alain Mollier4 1 1 2 2 University of British Columbia, Land and Food Systems Agricultural Research Service (ARS), US Department of Agriculture 3 Institute of Agricultural Sciences, Group of Plant Nutrition 4 University of California, Department of Land, Air and Water Resources 5 Stanford University, Biology Cover crops affect phosphorus (P) cycling through several processes in agricultural systems. Cover crops can mobilize soil P found in pools of low plantavailability (via changes to soil pH, organic acids and enzyme activity), take up soil P (initiating a reequilibration of different soil P pools), and transfer P to soils and subsequent crops when cover crop residues decompose. We studied the effects of legume, cereal, and mustard cover crops on soil P cycling in intensive agricultural systems of California, using two long-term field experiments, two greenhouse experiments (one on P mobilization and one on P transfer from residues using 33P), and farm-gate budgets. Within these experiments, we measured plant biomass and nutrient content, soil properties (pH, enzyme activity, organic acids), soil P pools (resin, organic, microbial, Hedley fractions), and P fluxes to determine the effects of cover crops on soil P dynamics. In both field and greenhouse conditions, legume cover crops had a greater potential to mobilize soil P than other cover crops, although in practice they did not increase soil P availability. In contrast, cereals had larger P uptake than other cover crops, resulting in stronger effects on P cycling and higher soil P availability. Regardless of cover crop type, P taken up in cover crop biomass was recycled rapidly in these systems, as cover crop residues contributed similarly to soil pools and a subsequent crop P uptake than mineral fertilizer. However, cover crops had a relatively small effect on farm-gate P budgets and long-term soil P dynamics compared to P inputs (fertilizer, compost, manure) and crop P export. Therefore, while cover crops affected soil P cycling in these intensive agricultural systems, their impact was relatively minor. 31 | P a g e Université de Bordeaux, Science and Environment Agriculture and Agri-Food Canada 3 Université Laval, Soil and Agricultural Engineering 4 Institut National de la Researche Agronomique (INRA) UMR No-tillage (NT) is agricultural practice recommended in context of conservation agriculture. Consequently, the NT management systems often cause the stratification of phosphorus (P) with depth with high concentrations of P at the upper soil profile depending on the rate of P fertilization, as well as the alteration of soil properties. As a result, corn roots distribution and morphology could be modified. However, little is known about how the root system in soil profile responds to different combinations of tillage and P supply. A study was conducted at L’Acadie (Québec, Canada), on a clay loam soil in 2014 to quantify the effects of different tillages and P fertilization rates on corn (Zea mays, L.) root distribution and morphology. This long term field experiment, initiated in 1992, is a split-plot device with principal factor of tillage (mouldboard plow (CT) and no-till (NT)) and sub-plot factor of P fertilization (0, 17.5 and 35 kg P ha-1 biennially applied) under a cornsoybean rotation (Ziadi et al. 2014). Root samples were collected at R1 (silking) stage by 8 cm diameter soil cores. Cores were taken up to a depth of 40 cm at 5 cm, 15 cm and 25 cm perpendicularly to the corn row and were cut out at 5 depths: 0-5 cm, 5-10 cm, 10-20 cm, 20-30 cm and 30-40 cm. After washing and sieving, root length and surface area of 1 st order (diameter > 0.08 cm), 2nd order (diameter range from 0.02 to 0.08 cm) and 3rd order (diameter < 0.02 cm) roots were measured on scanned image with the software WinRHIZO (Regent Instruments Inc., Quebec, Canada). The root distribution and morphology pattern in the soil profile showed no significant differences between NT and CT. The 35 kg P ha-1, biennially applied, tends to increase RLD by 27% and 43% to the fertilization of 0 and 17.5 kg P ha 1 as well as the root surface area (27% and 49%, respectively). Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Impact of Phosphorus Fertilizer Placement on Crop, Soil, and Run-Off Water in a Brown Chernozen in South-Central Saskatchewan Crop agronomic responses to phosphorusbased swine manure application and manure phosphorous source coefficients under longterm corn-soybean rotation Blake Weiseth, Jeff Schoenau, Derek Peak Tiequan Zhang1, X.J. Hao2, C.S. Tan1, Y.T. Wang1, Tom Welacky1, J.P. Hong2 University of Saskatchewan, Soil Science An apparent dichotomy exists regarding Soil Test Phosphorus (STP) levels in agricultural soils on the Canadian prairies, where certain soils are classified as deficient for crop production and require P fertilizer addition while others are excessively enriched and can contribute to elevated P in run-off water. Crops with high P requirements such as soybean and canola often remove more P than can be safely applied with the seed, contributing to soil P depletion. A pot study was conducted where soybean was grown with varying rates of seed-placed fertilizer P. Rates of seed-placed P above 20 kg P2O5 ha-1 significantly reduced germination and emergence. However, higher than recommended rates of seed-placed fertilizer P (i.e. 40 kg P2O5 ha-1) did not significantly reduce soybean biomass production compared to the control treatment after 14 days of growth. A field study was conducted in 2014 to assess the effect that fertilizer P application method (seed row, deep banded, broadcast and incorporate, broadcast alone) had on soybean yield, P uptake, soil P forms, and residual P distribution. Seed placed and banded P fertilizer was more effective in increasing soybean yield and P uptake than broadcast fertilizer. Broadcasting resulted in higher concentrations of available P closer to the soil surface. The distribution of available P in the soil was assessed along with P forms using sequential extraction and XANES spectroscopy. Additionally, a quantitative assessment of the effect that fertilizer P application strategy has on influencing the off-site transport of P in runoff water was achieved through a simulated snowmelt runoff event followed by measurement of the dissolved and particulate P in the run-off water. Results of the P transport experiment will be discussed. 32 | P a g e 1 2 Agriculture and Agri-Food Canada Shanxi Agricultural University With increasing interest in adopting phosphorus (P)based manure application, a good knowledge of manure form-specific agronomic performance is needed to assure crop productivity and to safeguard the environment. We evaluated the effects of three forms of swine manure (Sus scrofa) (liquid, LM; solid, SM; and liquid manure compost, MC), each applied at 100 kg P ha-1 year-1, on crop yield, P uptake, and cumulative P agronomic efficiency (CPAE), in comparison with chemical fertilizer (CF), and the manure P source coefficients (PSC) under corn (Zea mays L.)-soybean (Glycine max L.) rotation in a Brookston clay loam soil for an eight-year period. Corn grain yield followed the order of LM > SM > MC, while soybean yield did not differ amongst the three forms of swine manure. Similar patterns were observed for total P uptake and grain P removal for both corn and soybean. Values of manure PSC were 1.14, 0.85 and 0.74 for corn, and 1.00, 1.02 and 0.93 for soybean, for LM, SM, and MC, respectively, when only crop yield was considered. When changes in soil test P (0-30 cm) were taken into account, the values of PSC were 1.10, 1.07 and 1.02 for LM, SM, and MC, respectively. The value of CPAE, defined as yield produced in a given year per kg of net P input since the first application, declined linearly with increases in net P input over time for both corn and soybean. It appeared that CPAE can be a useful measurement indicating use efficiency of long-term P application. Phosphorus-based manure application must be optimized with legacy P considered to maximize long-term use efficiency. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Organic matter distribution across particulate and mineral-associated fractions varies directly and interactively with cover cropping and tillage management Nitrification occurs in frozen agricultural soils – consequences on fate and management of fall-applied and soil residual N under cold climate Andrea Jilling, A. Stuart Grandy Martin Chantigny1, Denis Angers1, Philippe Rochette1, Claudia Goyer2 University of New Hampshire, Natural Resources and the Environment 1 2 The distribution of C and N across soil organic matter (SOM) fractions serves as an indicator for the nutrientproviding capacity of agricultural soils. Previous research has focused on the fractions deemed more labile or active, such as particulate organic matter (POM) or light fractions. However, there is increasing evidence that the fine fraction of agricultural soils may play a more dynamic role in short-term fertility. In this study, we examined whether contrasting tillage and cover crop regimes affected the quality and quantity of C and N in SOM fractions, with a specific focus on the silt and clay-associated component. Combining both sonication and wet-sieving techniques, we fractionated bulk soils into four distinct components: free POM (fPOM), occluded POM (oPOM), a coarse silt fraction, and mineral-associated organic matter (MAOM). The inclusion of a rye cover crop significantly increased the amount of organic matter recovered as fPOM, but decreased OM retained within the coarse silt fraction. The significant influence of management on oPOM and MAOM weights manifested as a tillage-by-cover interaction. With respect to C and N contents of fractions, both tillage and cover crop treatments produced significant effects, although in contrasting ways. The more conservative tillage approach significantly increased the C and N contents of oPOM by 27 and 22% respectively. This parallels the prevailing understanding that POM will respond quickly to changes in soil management. On the other hand, within the coarse silt and MAOM fractions, cover crops had a stronger influence, with rye increasing the N content across both by 38 and 22% respectively. The influence on MAOM C content was marginal, possibly reflecting a decoupling between C and N accrual in silt and clay fractions. In sum, cover crops and more conservative tillage approaches exert significant but variable influence on the distribution and potentially behavior of SOM. 33 | P a g e Soil & Crops Research and Development Centre, AAFC Potato Research Centre It was demonstrated that nitrification occurs in frozen agricultural soils, especially in clayey soils (Clark et al. 2009) and in soils where plant residues and animal manure are applied in the fall (Chantigny et al. 2002). As a result, nitrate gradually accumulates in the soil profile throughout the non-growing season, and is at high risk of being lost through leaching and denitrification during winter and spring melt. This would explain why in several field trials in Canada a major portion of soil residual N at harvest and fall-applied N was not recovered in the next spring (e.g. Nyiraneza et al. 2010; Chantigny et al. 2014). Moreover, it was found in some of those experiments that a significant portion of organic and clay-fixed N can also be lost during winter, indicating that other processes such as mineralization continue in frozen soils. Finally, recent research evidenced that 10 to 70% of annual N2O loss and 50 to 70% of annual N leaching loss occur in the non-growing season. The potential of some management practices to abate overwinter N losses, such as timing of manure application, presence of high C/N ratio crop residues, and use of nitrification inhibitors are currently tested. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Impact of Cover Crops and Organic and Mineral Fertilization on Canola Yields and Nitrogen Uptake Vaillancourt1, Vanasse1, Mathieu Anne Martin Chantigny2, Denis Pageau3, Denis Angers2 Nitrogen application rate, timing and history effects on corn nitrogen use efficiency Amal Roy1, Claudia Wagner-Riddle2, Bill Deen3, John Lauzon2, Tom Bruulsema4 1 Brandon Research Centre, AAFC University of Guelph, Environmental Sciences 3 University of Guelph, Plant Agriculture 4 International Plant Nutrition Institute 1 2 Cover crops are known to improve soil structure and to contribute to N fertilization in the case of legumes. The aim of this study is to evaluate the impact of a legume cover crop (mixture of Trifolium repens and T. pratense) combined with mineral and organic nitrogen fertilizer on canola (Brassica napus) N uptake and yields. The experiment will be repeated twice on three growing seasons (2013-2014 and 2014-2015) on a poorlydrained heavy clay and a well-drained sandy loam. The design is a factorial split-plot, with the presence or absence of cover crop as main plots, and as sub-plots, nine fertilizer treatments, either mineral or organic (pig slurry) at rates ranging from 0 to 150 kg N•ha-1. Cover crop biomass N, canola N uptake and yields, soil mineral N, aggregate stability, and microbial biomass have been measured; only the data on plant N uptake and yield will be presented. The data from the first experiment show that the cover crop biomass contributed 27.5 to 70.3 kg N•ha-1 on the heavy clay and 89.6 to 157.8 kg N•ha-1 on the sandy loam. Canola yield increased with increasing N fertilizer rate, the mineral fertilizer yielding more than the organic fertilizer. With the mineral fertilization, yields stabilized at a rate of 100 kg N•ha-1, whereas they kept increasing with rates up to 150 kg N•ha-1 with the organic fertilization. On the sandy loam, canola yields were higher following the cover crop, while on the heavy clay, the increase was limited to rates below 100 kg N•ha-1. Preliminary results show that a clover cover crop can contribute significant amounts to canola N uptake. The loss of the applied nitrogen (N) from crop fields to the environment causes both economic loss and environmental pollution; thus assessing the efficient use of N is crucial both for economic benefit and environmental protection. Previous studies suggest that the rate and the timing of N application can be finetuned to mitigate N losses from soil. This study examined the effect of timing, rate, and history of ureaammonium nitrate application on nitrogen use efficiency (NUE) over 5 years as part of a field trial that started in 2009 at Elora, ON, Canada. The five N rates investigated were 30, 58, 87, 145 and 218 kg N ha-1; the two timings were at planting and at the 8th leaf stage. The two histories studied consisted of applying the N rate treatments on plots that had received in the previous year (i) the recommended rate of 145 kg N ha 1, or (ii) the same N rate over the duration of the trial. The maximum economic rate of nitrogen (MERN) along with corresponding grain yield, and two NUE terms, agronomic efficiency (AE) and recovery efficiency (RE) were determined for each year for the studied treatments. In the five years of the experiment, neither the timing nor the history of N application exerted any significant impact on estimated MERN and the corresponding corn grain yields and AE. RE at low rates of application was significantly higher with N applied at the 8th leaf stage in 2011, and with long-term history of N application in 2012. Université Laval 2 Soil & Crops Research and Development Centre, AAFC 3 Agriculture and Agri-Food Canada 34 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of organic matter on nitrogenase metal cofactors homeostasis in the soil bacterium Azotobacter vinelandii under diazotrophic conditions Noumsi1, Origin of inositol phosphates in residual fractions derived from Hedley fractionation in Chilean Andisols Maria de la Luz Mora1, Gabriela Velasquez1, Cornelia Rumpel2, Leo Condron3, Benjamin Turner4, Marcela Calabi1 Pourhassan1, Christelle Jouogo Nina Romain Darnajoux1, Thomas Wichard2, Vincent Burrus1, Jean-Philippe Bellenger1 1 Universidad de la Frontera Université Paris VI, AgroParisTech 3 Lincoln University, Agriculture and Life Sciences 4 Smithsonian Tropical Research Institute 1 2 Biological nitrogen fixation (BNF) can be catalyzed by three isozymes of the enzyme nitrogenase: Monitrogenase, V-nitrogenase and Fe-nitrogenase. The relative importance of these isozymes to BNF in natural habitats likely depends on the ability of N2 fixers to acquire the metal cofactors (Mo, V and Fe). While V is in average 50 to 200 times more abundant in the earth crust than Mo (Hans Wedepohl, 1995), our understanding of Mo and V availability to N2 fixers in soil is still limited. Mo, and likely V, have been shown to be strongly complexed by tannin-like compounds in the topsoil (leaf litter layer), and by organic matter and iron oxides in deeper soils across a wide range of pH (Wichard et al., 2009). While, this complexation might help preventing Mo leaching, it can further limit Mo bioavailability to N2 fixers. Here, we show how metal bioavailability can be affected by the presence of tannic acid (organic matter), and the subsequent consequences on diazotrophic growth of the soil bacterium Azotobacter vinelandii. In the presence of tannic acid, A. vinelandii adapts its strategy of metal acquisition by producing more metallophores. Surprisingly, this overproduction leads to a regulated and simultaneous uptake of Mo and V until both reach optimal concentrations required to sustain BNF. The associated nitrogenase genes exhibit reverse expression, with a decrease in nifD expression and an increase in vnfD expression. Thus, in conditions of limited metal bioavailability, A. vinelandii takes advantage of its alternative nitrogenases to ensure optimal diazotrophic growth. Phosphorus (P) is a finite resource and continued inputs are required to maintain the productivity of agroecosystems, although most applied P is retained in soil. Sequential fractionation has been widely used to study the nature and dynamics of soil phosphorus (P). One of the main limitations of this approach is that in many soils a significant proportion of total P is not extracted, this P was defined as residual P. The nature and bioavailability of this ‘residual P’ is poorly understood. The objective of this study was to isolate, quantify, and characterize residual P following Hedley fractionation in a range of Andisols developed under grazed pasture by alkali extraction and 31P nuclear magnetic resonance (NMR) spectroscopy. Residual P accounted for 45–63% of the total soil P, of which 44– 70% was inorganic orthophosphate. Organic P accounted for 25–46% of the residual P, the majority of which occurred as orthosphosphate monoesters (predominantly myoand scyllo¬-inositol hexakisphosphate) while no orthophosphate diesters were detected. These results provide the first direct determination of the chemical nature of residual P in soils, demonstrating that is consists of a mixture of inorganic P and organic P in relatively stable forms. The findings of this study provide the basis for the development of new agronomic approaches designed to enhance the utilization of residual soil P and thereby contribute to improving overall P use efficiency and reducing P inputs. Université de Sherbrooke, Chemistry 2 Friedrich Schiller University, Inorganic and Analytical Chemistry 35 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S2: Dynamics of Pollutants in Soil 36 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Environmental model of P saturation for acidic soils of Prince Edward Island Rim Benjannet1, Judith Nyiraneza2, Lotfi Khiari1, Barry Thompson3 Application of the Root Zone Water Quality Model (RZWQM) to stimulate fate and transport of emerging substances of concern in soils receiving long-term biosolids application 1 Université Laval Crop & Livestock Research Centre, AAFC 3 PEI Department of Agriculture and Forestry Weixi Shu1, Gordon Price1, Rob Jamieson2 2 1 Dalhousie University, Agriculture Dalhousie University, Process Engineering and Applied Science 2 In the Prince Edward Island (PEI), the potato is one of the main agricultural productions. This crop is particularly demanding in phosphorus (P). However, P is applied in excess to the amount removed by potatoes in this region to compensate the P fixation by Al and Fe commonly found in acidic soils. This increases the risk of P accumulation in soils and of nonpoint pollution. To improve P management in PEI crop productions, it is essential to develop an agrienvironmental P saturation index as unifying criterion for agronomic and environmental interpretation for sustainable potato production. Our objective is to develop an environmental model of P saturation for agricultural PEI soils using a routine laboratory Mehlich-3 soil analyses procedure for assessing the P environmental risk. In this study, 141 soils from various agri-pedo-climatic regions of PEI were selected. A routine soil characterization was made: organic matter, pHwater, pHSMP and Mehlich-3 extraction (P, Al, Fe, Ca, Mg, Zn and Cu). The degree of P saturation (DPS) was determinated using the oxalate ammonium extraction procedure. A test of P desorption (Pw) using the Sissingh method was applied. Exchangeable aluminum was extracted by NH4Cl procedure. According to preliminary results, the environmental model expressing the ratio between [P/Al]M3 and Pw depends on the degree of soil acidity. For strong to very strong acid soils (4.5<pH<5.5), the model is expressed as follows: Pw=0.599[P/Al]M3-1.831 (n=54; R2=0.87; P<0.05) with an environmentally critical [P/Al]M3 percentage of 19%, corresponding to the critical DPS value of 25% proposed in the Netherlands. For moderate acid to neutral soils (5.6<pH<7.3), the model is Pw=0.729[P/Al]M3-0.661 (n=87; R2=0.85; P<0.05) and the critical [P/Al]M3 percentage is 14%. Mehlich-3 can be used as an environmental indicator of the risk of phosphorus pollution. Soil acidity degree is a good criterion to group soils from contrasting soil types. 37 | P a g e Biosolids contain emerging substances of concern (ESOCs) which are not removed by conventional wastewater treatment processes. Land application of biosolids can provide entry of ESOCs into the soil system. Better understanding of the fate and transport of ESOCs in biosolid-amended soils is required to assess and manage the risk of adverse effects on the environment and humans. The Root Zone Water Quality Model (RZWQM) is a comprehensive onedimensional, numerical agricultural systems model used to predict the effects of agricultural management on crop production and environmental quality. The pesticide transport sub-model of the RZWQM is a costeffective tool to simulate the behavior of the pesticides in the agricultural system. The purpose of the study is to test the potential to simulate the fate and transport of ESOCs by using the same sub-model. A set of field based lysimeter cells were used to collect water samples from biosolid-amended soils. The rates of ATB application included a 0, 14, and 42 Mg ATB ha-1 which were applied to microplots within each cell residing over a drainage port. The concentration of two types of ESOCs, ciprofloxacin and naproxen, were analyzed by GC/MS and used to validate the model simulation. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Dynamics of PAH and derived organic compounds in a soil-plant microcosm spiked with 13C-phenanthrene Assessment of triclosan toxicity to the earthworm Eisenia fetida under laboratory conditions using GC-MS metabolomics Johanne Cennerazzo1, Alexis deJunet1, JeanNicolas Audinot2, Patrick Grysan2, Corinne Leyval1 Daniel Gillis1, Gordon Price2, Shiv O. Prasher1 1 2 McGill University, Bioresource Engineering Dalhousie University, Engineering 1 Université de Lorraine, Laboratoire des Environnements Continentaux 2 Luxembourg Institute of Science and Technology In many former industrial regions such as in Lorraine (France) large areas of brownfield are contaminated by Polycyclic Aromatic Hydrocarbons (PAH). Despite a thorough research, there is still a lack of knowledge concerning the processes governing the fate of PAH in contaminated soils and in plant rhizosphere. These are the key issue to predict their dynamic in contaminated soil and to assess the feasibility of using plants for remediation. The objectives of this study were to specify the fate of PAH in soil–plant system by (i) estimation of transfer, retention and degradation processes, (ii) identification of derived organic compounds from PAH, and (iii) localization of PAH and these derived organic compounds in soils. To this end, a mesocosm experiment was conducted on a soil planted with perennial Ryegrass (Lolium perenne) and spiked with a labeled model PAH: 13C-phenanthrene (13C-PHE). IRMS analyses were performed on soil matrix before and after PAH extraction, and on dried plant tissues in order to evaluate the repartition of carbon originated from 13C-PHE between the different fractions of soil and plant. The first results highlighted an isotopic enrichment in the soil residue indicating the presence of 13C-bound residue into soil. NanoSIMS technique was used to provide a map of the 13C distribution in roots. The results revealed no signal inside the roots but a probably carbon labeled accumulation in adherent bacteria. We are also investigating (i) the molecular structures of these derived organics compounds entrapped in the soil matrix with 13C-NMR and pyGCMS, and (ii) the nature of nitrogen and oxygen PAH-metabolites present in the extract by using GCMS. 38 | P a g e Triclosan (TCS) is a prevalent contaminant in biosolids and has previously been detected in soil and earthworms where biosolids have been used in agriculture. The goal of this study was to evaluate the toxicity of TCS to earthworms using a metabolomicsbased approach. Toxicity of TCS was assessed using a filter paper contact test. Eight replicates were exposed to six concentrations (0, 0.0001, 0.001, 0.01, 0.1, and 1 µg TCS cm-2), with mortality assessed after 24 and 48 hours. Average weight loss decreased relative to the control at the two lowest concentrations and increased with the three highest. Alanine, glycine, valine, leucine, serine, putrescine, mannitol, glucose, and inositol were significantly affected by TCS concentration. Although not all differences are significant, in some cases metabolite concentrations followed the same pattern as weight loss, increasing in the two lowest exposure concentrations and decreasing at higher concentrations where mortalities were present. Putrescine followed an opposite trend, decreasing at low exposure concentration and increasing in high concentration. Amino acids were highly correlated with each other, as were the carbohydrates. Weight loss was negatively correlated with mannitol, glucose, and inositol, and positively correlated with alanine. Results show that triclosan can alter the metabolic profile of earthworms under laboratory conditions. Exposure concentration can affect the direction of the shift in metabolite concentration and needs to be considered when looking for biomarkers of exposure. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Conservation of insecticidal activity of CrylAc adsorbed on three contrasting soils and persistence with time Sorption and Desorption Kinetics on Mixtures of Non-Steroidal Anti-Inflammatory Drugs in Different Textured Agricultural Soils Truong Phuc Hung1, Yasmina El Khoulali1, Roger Frutos2, Hervé Quiquampoix1, Siobhan Staunton1* Yu Zhang, Gordon Price, Rob Jamieson 1 INRA, UMR Eco & Sols Cirad, UMR Intertryp 2 The insecticidal proteins known as Bt proteins or Cry proteins are also produced by the soil-endemic bacterium, Bacillus thuringiensis and more recently by genetically modified crops. After release into soil the fate of these proteins and their ongoing biological activity depends on their interactions with soil. The amount of Cry protein detectable in soil by immuneassay after chemical extraction is known to decline with time. There is ongoing debate as to the balance between biotic and abiotic factors in the environmental fate of Cry and the soil factors that determine persistence remain poorly understood. We incubated Cry1Ac Bt toxins in contrasting soils subjected to different treatments to inhibit microbial activity, in order to establish the importance of biotic and abiotic processes in Bt toxin fate. The toxin was chemically extracted from each soil and immunoassayed. Biotests using the target insect larva, Manduca sexta, were also carried out. There was a marked decline of extractable toxin after incubation for up to four weeks at 25°C. Toxicity was maintained in the adsorbed state for each of the soils, but had been lost after 2 weeks incubation at 25°C. The decline in extractable protein and toxicity were much slower at 4°C but there was no effect of soil sterilization. The major driving force does not appear to be microbial. The major cause is probably time-dependent fixation of adsorption protein, leading to a decrease in the extraction yield in vitro, which is paralleled by decreasing solubilization in the larval gut. 39 | P a g e Dalhousie University Non-steroidal, anti-inflammatory drugs (NSAIDs) are widely used pharmaceutical products with analgesic and anti-inflammatory effects. Land application of biosolids as a source of crop nutrients and organic matter is a common agricultural practice worldwide, but can also potentially introduce pharmaceuticals into the soil environment. The presence of pharmaceuticals in terrestrial and aquatic environments, even at very low concentrations, is emerging as an issue of concern for ecosystem health. Sorption and desorption are important processes that affect a multitude of environmental behaviors of a chemical, including movement, plant uptake, and bioavailability. In this study, the sorption-desorption behavior of a mixture of NSAID pharmaceuticals was studied in two different soils from Ontario and Nova Scotia. The sorptiondesorption experiments were performed according to the OECD test Guideline 106, and the experimental data obtained were analyzed to gain more insight regarding the processes involved in adsorption and desorption. Current data showed that the adsorption affinity and desorption rate of the four pharmaceuticals found in soil on Mt. Hope, Ontario, was in the following order: ketoprofen > diclofenac > naproxen > ibuprofen. Competitive sorption between naproxen and other three compounds in the mixture condition was not significant in Mt. Hope soil. A larger portion of naproxen was desorbed when it existed individually. Further work will be conducted on the adsorption and desorption of a mixture of NSAIDs as a function of soil type. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluation of soil microbial communities as influenced by cruel oil pollution Eucharia Nwaichi1, Eugene Onyeike2, Lasbrey Opara3 1 University of Massachusetts Amherst 2 University of Port Harcourt 3 Macphed Ventures Ltd. The impact of petroleum pollution in a vulnerable Niger Delta community ecosystem was investigated by making a reasoned assessment of interactions in a first generation phytoremediation site and a crude oil freshly spilled agricultural soil. A community-level approach for assessing patterns of sole carbon source utilization by mixed microbial samples was employed to differentiate spatial and temporal changes in the soil microbial communities. Genetic diversity and phenotypic expressions were also measured for a more holistic perspective. The 5’-terminal restriction fragments generated after Csp digestion of 16S rRNA gene correlated with observed DNA concentrations in the community profile and revealed loss of diversity with pollution. Crude oil pollution significantly reduced the phosphomonoesterases and respiratory activities and values were pH dependent. There were no expressed dehydrogenase activity in initial spill site but were enhanced with phytoremediation. Factor analysis of predictors and independent variables indicates that respiratory, alkaline phosphatase and α-glucosidase activities could be used to explain underlying factors. Positive soil – microbial plant interactions were observed. 40 | P a g e The assessment of non-point-source of contamination on the Kinetics of some potentially toxic elements desorbed from contaminated soils Alaa Zaghloul, M. Sader, Soad El-Ashry, E. Hoballa National Reseach Center, Dokki, Cairo, Egypt After building of Grand Ethiopian Renaissance Dam (GERD), potential hazards were established through the Nile water shortage, especially at the end of Egyptian irrigation canals. This situation enforced farmers to use low quality water sources vulnerable to many types of potential toxic elements PTEs arising from variety sources. The aim of this work is to compare between four Egyptian types of contaminated soils collected from Kafr El-Shekh, Abo-Rawash, and Sinai governorates received different types of low quality waters with different residence times ranged between 35 and 70 years, in their PTEs release capacities. The calculated Zinc Equivalent ZE values of soil samples, as a soil contamination parameter, ranged between 550 and 680 with critical value equal to 250, which represent a bad situation and prohibit the use of such soils in producing edible plants. The obtained results revealed that with exception of 1st order equation, all used kinetic models were well described the rate of potential toxic elements desorption from the studied soils by having high and significant coefficient of determination (R2) and low standard error SR varied according to type of model used. The fat of PTE's desorption from soils were mainly depended on the mechanisms of sorbates such as type of pollutants studied, ionic radius, electronegativity, valance charge, concentrations in soil ecosystem and ionic strength, and others related to sorbents such as organic matter OM content, pH, Eh, amorphous materials, type and content of clay minerals in used soils which played an important role in accumulation and release of PTEs, also it could be a good indicator for soil pollution status. Concerning the effect of residence time or the time of soil exposed to pollutants in irrigation water, data showed that this parameter consistently influenced the concentrations of pollutants in soils and influenced the rate of PTE's desorption. Different mechanisms influenced the rate of PTEs desorption took place were discussed. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Heavy metal concentration in soil in the Tailing Dam Vicinity of an Old Gold Mine in Johannesburg, South Africa Experimental assessment of copper and cobalt phytoavailability in soils from metalliferous ecosystems in Katanga Roseline Olobatoke, Manny Mathuthu Kaya Muyumba Donato1, Olivier Pourret2, Amandine Liénard1, Michel-Pierre Faucon2, Gregory Mahy1, Gilles Colinet1 North-West University, CARST Soil contamination with heavy metals is a serious concern to food production and human health. Heavy metals are released into the environment through natural and anthropogenic sources. However, man’s industrial engagements such as mining and its associated activities have often resulted in elevation of heavy metal concentrations in soil, particularly in areas around mining waste pile and tailings, leading to soil degradation. The present study was conducted to evaluate the impact of tailings from an old mining site on heavy metal contamination of soil. Using a GPS to map out different sites around the tailing dam, soil samples were taken from under grassland at the different sites, at depths of 5 cm and 1 m, using a shovel/hand-held auger. The samples were prepared, acid-digested and analyzed for a multi-element suite by Inductively Coupled Plasma Atomic Emission Spectrometry. Results showed heavy metal concentration in order of Cr > As > Zn > Mn > Cu > Ni > Pb > Sr > Hg. Most of the soil samples contained high concentration of As (13.46 – 234.6 mg/kg). Soil concentrations of As, Hg, Cr and Mn also decreased with distance from the dump material. Variations in metal concentrations between the different soil depths did not suggest any definite movement pattern of the metals within the soil strata. Single contamination index of each pollutant, calculated according to the Canadian Environmental Quality Standards for Soils revealed high and medium pollution grades for As (index = 3.6) and Cr (index = 2.0) respectively. Arsenic is a metal associated with gold ore and soil pollution by such metals can make it infertile and unsuitable for plants. Thus this study showed that lack of proper control or management of mine wastes could pose a serious threat to food security as well as human health in the mining areas. 41 | P a g e 1 2 Université de Liège, Gembloux Agri-Bio-Tech HydrISE, Institut Polytechnique A pot experiment was conducted in order to evaluate factors driving bioavailability of Cu and Co in soils from metalliferous ecosystems of Katanga. Anisopappus davyi is a common species among vegetation from copper hills. Soil samples were taken according to vegetation units and plants of A. davyi were grown during four months on eight soils from ecosystems and two reference soils. The geochemical and chemical characterization of soils showed clear links the nature of vegetation they support on the field and with the degree of soil development. The swards and rocky steppe were clearly different from the other steppes and from forest, because of nature of parent material and differences of Cu and Co contamination but also differences in acido-basic and nutrient status. The time since contamination was another discriminating factor. The highest levels of contamination in soils generated important death of A. davyi. The order of magnitude of bioavailable content in Cu and Co above which the growth of the plants was drastically stopped was 1 000 mg•kg-1 and 50 mg•kg-1 for Cu and Co, respectively. This accessorily showed that A. davyi could be used as indicator of trace element bioavailability but more work is needed to define the range of ecological conditions for that species. The comparison of plant and soil content (measured and modelised with WHAM) showed that the chemical extraction solution used was appropriate to predict the plant content. The geochemical modeling is also potentially useful to discriminate soils according to predicted distribution of Cu and Co among soil constituents and especially on the most mobile fractions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A correlation between nickel/ metal mineralogy and its bioaccessibility in artificial (OECD) spiked soils Adding silver nanoparticles to soils directly or in biosolids leads to differences in Ag speciation. Luba Vasiluk1, Michael Dutton2, Andrea Amendola3, Lisa Van Loon4, Beverley Hale1 Heather V.A. McShane1, Dina M. Schwertfeger2, Timothy D. Schwinghamer3, William H. Hendershot1 1 University of Guelph, Environmental Sciences Vale Ltd. 3 Golder Associates Ltd. 4 University of Saskatchewan, Canadian Light Source Inc. 2 In Ontario, Site Condition Standards for soils are based on the “total” metal in soil and it is the exceedance of those that may prompt an ecological RA; therefore knowledge of a change and transformation of metals in sites that are exceeding these standards is critical. The effect of field-ageing on nickel (Ni) in soil was studied using artificial OECD soils spiked with four Ni forms (NiSO4, NiO, NiS, Ni3S2) and Ni mixtures (NiO/Ni3S2 and NiS/Ni3S2). The mineralogy of the Ni in artificial soils after ageing was characterized using XANES and Zatka leaching protocol, with the goal of explaining variation in Ni bioaccessibility among soils. Total Ni recovery after artificially ageing the soils, was variable among Ni forms and Ni was more readily leached from soils amended with NiSO4. The XANES for the NiO- soil indicated that the oxide remained unaffected. In all other samples, the predominant species were Ni2+ salts and NiO. The XANES indicated that ageing resulted in an oxidation of the Ni in the samples. Zatka leaching analysis of soils spiked with NiO alone was in a good agreement with the XANES. Zatka analysis showed that Ni2+ salts were not soluble in the water, but soluble by ammonium citrate and likely to be NiCO3. To evaluate the bioaccessibility of Ni and its correlation with mineralogy, two in vitro methods were used – PBET and SBRC. Overall, Ni bioaccessibility using SBRC was almost twice as high as Ni bioaccessibility using gastric PBET. Linear regression between bioaccessible Ni and ionic Ni estimated by XANES had a better correlation with SBRC values, thus likely to be more useful in discerning differences among soils. Ni "accessibility" from soil is a function of speciation, particle structure, and dissolution kinetics. Speciation analysis, sequential extraction provides the underlying scientific context supporting the use of bioaccessibility in RA. 42 | P a g e 1 Dept. of Natural Resource Sciences, McGill University Biological Assessment and Standardization Division, Environment Canada 3 Dept. of Plant Science, McGill University 2 Silver nanoparticles (nAg) are being added to an increasing number of commercially available products. A proportion of these will enter the waste water system and may be applied to agricultural soils in biosolids (sewage sludge). The potential bioavailability and effects of these novel particles to terrestrial organisms are under investigation. Most fate and toxicity studies to date have focused on direct application of nAg to soils, but the prior exposure to biosolids is likely to modify nAg fate, and potentially bioavailability. In this study we compared the fate of a commercial source of nAg following its addition to soils either directly or in biosolids. The speciation of Ag in soil extracts was measured using a variety of techniques including potentiometry, single particle inductively-coupled mass spectroscopy, transmission electron microscopy, and EXAFS. Extracts from soils receiving the nAg+biosolid treatment had significantly lower Ag+ activity, but a 30 times higher occurrence of Ag-containing nanoparticles, than soils amended directly with nAg. EXAFS analysis revealed that nanoparticle surfaces in the biosolid treatments were composed of Ag2S. These results demonstrate that nAg nanoparticle transformations depend on the exposure medium. They suggest that nanotoxicity tests in which nAg is applied directly to soils are unlikely to replicate organism responses to soils which receive nAg through application of biosolids. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Influence of Mowing and Narrow Grass Buffer Widths on Reductions in Sediment, Nutrients, and Bacteria in Surface Runoff Jim Miller1, Tony Curtis1, David Chanasyk2, Sharon Reedyk1 1 2 Agriculture and Agri-Food Canada University of Alberta Little research has been conducted on the effect of mowing and buffer width on the effectiveness of shortwidth (< 10 m) native grass buffers to filter sediment, nutrients, and bacteria. A two year (2011-2012) field study was conducted on native rangeland in southern Alberta. The treatments of mowing and buffer width (1.5, 3, 6 m) were evaluated using a randomized complete block design with four replicates. The buffer plots were pre-wet with distilled water. A spiked solution was then applied to each plot using a run-on distribution device and the runoff collected every 10 min for 30 min once the runoff started discharging from the plot. The volume of runoff, and percent reduction in concentration and mass of sediment (total dissolved solids or TSS), phosphorus (dissolved reactive P or DRP, total P), nitrogen (total N), and bacteria (E. coli, total coliforms) in runoff were determined. The findings did not support our hypothesis that percent reductions in concentrations and mass for sediment, nutrients, and bacteria were greater for mowed than unmowed buffers. In contrast, the findings supported our hypothesis that increasing buffer width would significantly (P < 0.05) decrease mass (but not concentration) of sediment, nutrients, and bacteria in runoff. The significant mass reduction was attributed to a reduced runoff ratio caused by longer residence time and greater infiltration in the wider buffers. Mass reductions for the three buffer widths ranged from 29 to 92% for TSS, 22 to 93% for DRP, 38 to 93% for total P, 23 to 92% for total N, and between 61 and 94 % for E. coli and total coliforms. These findings suggest that buffer width but not mowing may reduce runoff quantity and improve runoff quality over the short-term. 43 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S3: Soil Microbiology 44 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial Resource Partitioning in Microhabitats of Soils Ellen Kandeler, Franziska Ditterich, Aurelia Gebala, Susanne Kramer, Sven Marhan, Christian Poll Influence of substrate availability and environmental conditions on microbial communities and enzyme activities in topsoil and subsoil habitats Sebastian Preusser, Sven Marhan, Christian Poll, Ellen Kandeler University of Hohenheim, Soil Science and Land Evaluation University of Hohenheim, Soil Science and Land Evaluation Microbial assimilation of soil organic carbon is an important process in global carbon cycling, since it determines the magnitude of microbial biomass in soils and controls processes leading to soil carbon stabilization. Mechanisms and controls in microbial carbon assimilation play also a fundamental role in regulating land-atmosphere interactions. Nevertheless, microbial biogeochemistry is still one of the greatest uncertainties in Earth system models. Therefore, capturing key aspects of microbial mechanisms (e.g. the differences in bacterial and fungal physiology) is an urgent requirement to improve these models. Whereas direct linkage of genomes to global phenomena is still a great challenge, many connections at intermediate scales are viable with integrated application of powerful analytical and modelling techniques. This integration could enhance for example our capability to develop microbial strategies for capturing and sequestering atmospheric CO2 and/or evaluate thermal adaptation of decomposer communities in warming soil. Recent studies of our group disentangle the herbivore and detritivore pathways of microbial resource use at biogeochemical interfaces of soils, identify the key players contributing to these two different pathways, and determine to what extent microbial substrate use is affected by environmental controls. To follow the kinetics of litter and root decomposition and to quantify the contribution of key players, we used isotopic approaches like PLFA-SIP and ergosterol-SIP. It was shown that bacteria and sugar consuming fungi initiated litter decomposition in a microcosm experiment during the first two weeks, whereas higher fungi started to grow after the depletion of low molecular weight substrates. Analyses of PLFA-SIP revealed that fungi assimilated C directly from the litter, whereas bacteria took up substrates from the soil and therefore depended more on external transport processes than fungi. 45 | P a g e Microorganisms involved in carbon cycling face different habitat conditions in topsoil and subsoil environments. While the habitat conditions influencing the abundance of microorganisms in topsoil are well investigated, these dynamics have been largely unexplored in deeper soil horizons. We investigated both the effect of different substrate availabilities and the influence of altered environmental conditions on the enzyme activity and the abundance and composition of microbial communities in topsoil and subsoil samples of a podzolic Cambisol from a European beech (Fagus sylvatica L.) forest in Lower Saxony, Germany. Therefore, we conducted a reciprocal soil transfer experiment with microcosms filled with soil from 20 cm and 120 cm soil depth and with the addition of different amounts of 13C labelled cellulose. In order to follow the temporal development, soil samples were taken after one, four and twelve months. Environmental measurements included pH, soil water content, carbon and nitrogen content. 13C microbial biomass was determined using the CFE method. The composition of the microbial communities was analyzed with the 13C PLFA method. Additionally, abundances of bacteria, fungi, archaea and seven of the most important taxa specific groups of bacteria were evaluated with qPCR. Moreover, the activities of seven enzymes (Xylanase, Peroxidase, Phenoloxidase, β-Xylosidase, N–Acetyl– α–Glucosaminidase, α-Glucosidase, Cellulose 1,4-βCellobiosidase) were determined. Both topsoil and subsoil samples show a temporal development with the greatest significant changes at the second sampling date. However, the causes of these changes are different. While in the subsoil samples most changes in the microbial communities and enzyme activities are caused by the transfer and the associated changes of the environmental conditions, the amount of added substrate is the main driving factor in the topsoil samples. This study provides a deeper understanding of the influencing factors on abundance and composition of microbial communities in topsoil and subsoil habitats. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Stability of buried soil organic matter in cropland: What are the mechanisms? Bert VandenBygaart1, Bobbi Helgason2, Hannah Konschuh2, Angela Bedard-Haughn3, Adam Gillespie3, Ed Gregorich1 Methanogen community responses to a gradient of sulfur and metal contamination in Sudbury, ON peatlands Michael Carson, Nathan Basiliko Laurentian University 1 Eastern Cereals and Oilseeds Research Centre, AAFC 2 Saskatoon Research Centre, AAFC 3 University of Saskatchewan, Soil Science In cropland soils prolonged erosion can result in the deposition of an inverted soil profile downslope, burying original and upslope A horizon materials at depth. These buried soils have been shown to represent a large stock of soil organic C which may be vulnerable to loss due to changes in management or climate. Our aim in this research was to characterize biodegradability of C in buried A horizon soils at 6 sites in diverse agricultural regions across Canada. Phospholipid fatty acid (PLFA) profiling indicated the presence of substantial (ca. 15 - 20 nmol PLFA g-1 soil) viable microbial biomass in the buried material at St. Denis, SK which was correlated with SOC (r = 0.40; p < 0.001) through the profile. Community composition was related to the origin of the soil in the landscape but was not correlated with current SOM composition as measured by C-K-edge-XANES which showed an enrichment of microbially-processed SOM biomarkers in the buried A horizons. High-throughput sequencing showed that there were changes in the bacterial and fungal community composition with depth and a strong dominance of the Verrucomicrobia Phyla in the buried C-rich material which suggests a potential ecological niche for these organisms. Intact and disturbed fresh soil cores incubated for 62 d showed that C decomposition was significantly restricted in the C-rich buried soils, thus confirming the stability of this C. While there was an increase in abundance and a shift in microbial community composition over the 62 d incubation, these changes did not appear to result in enhanced SOM decomposition. 46 | P a g e Peatlands cover a disproportionately high amount of land area in Canada and represent an immense global store of biospheric carbon and freshwater, serving critical ecosystem functions that link terrestrial and aquatic systems. However under current and future environmental change, peatlands are at high risk for altered hydrology and plant community composition, both which can lead to substantial losses of stored carbon. More recently, interest in the microbial communities responsible for carbon turnover in peatlands has increased. In particular the methanogens are of great interest due to their potential to produce large amounts of the potent greenhouse gas methane. However our current understanding is limited. Prior studies have shown that pH, organic matter quality, temperature, active vegetation, and water table position play significant roles in C and specifically CH4 cycling. Fewer studies have looked at the role metals and sulfur play in methane production. Sudbury, Ontario offers a unique study system with a history of metal smelting (primarily Ni and Cu) and subsequent metal and sulfate deposition that has accumulated in regional upland soils and wetland systems. This research used an established pollution gradient across ten peatlands to determine how methane production and the methanogen communities have responded to past chronic high metal and sulfur input. Preliminary data indicate that distance from smelters plays a key role in potential methane production, functional gene (mcrA) abundance (quantitative PCR), and methanogen community composition (T-RFLP and MiSeq). In general methanogen abundance and methane production increase with distance from smelters. Additionally methanogen community composition is more similar across sites with similar levels of deposition. Taken together these data suggest that a history of high metal and nutrient deposition has significantly altered methanogen community composition, abundance, and methane production, with potential impacts on broad regional scales reflecting historic and contemporary anthropogenic deposition. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of Zeolite and Bacteria on Straw Decomposition and Greenhouse Gas Emission from Paddy Field Kazuyuki Inubushi, Shunsuke Hanazawa, Maasa Takahashi Chiba University, Horticulture Greenhouse gases, such as methane (CH4) and carbon dioxide (CO2), are released from paddy field, derived from organic matter decomposition by soil microorganisms. Particularly during flooding period, significant CH4 emissions are observed with organic matter-amended field, such as rice straw incorporation. In single crop system, rice is growing during summer time, harvesting in autumn and fallow in winter. Rice straw is chipped and is spread on the field at harvesting, then incorporated either autumn or early spring depending on soil moisture. When straw is incorporated into soil during warm aerobic condition, it is decomposed to be CO2, while during wet anaerobic condition, it creates CH4, which is 24 times stronger global warming potential as CO2. Therefore it is important to decompose straw effectively before flooding rice growing season. Microbial materials are available to enhance straw decomposition, but so far no study to examine the effect of microbial material on greenhouse gas emission from paddy field. We examined a commercial bacterial material “A” composed of Bacillus subtilis and Clostridium acetobutylicum and zeolite to measure the gas emission, soil redox condition and rice growth. Three types of paddy soils, sandy, clay and peaty, were collected around Sanmu city, Chiba, Japan and pot experiment was conducted with rice straw (RS), RS + bacterial material A, RS+ autoclaved A or no amendment. Similar experiment was also conducted in farmer’s field. We found that CO2 emitted more with bacterial material A, and slightly more with autoclaved A than RS only during aerobic pre-cultivated period, while more CH4 emitted during flooded rice growing period with RS only than with A and autoclaved A. Total global warming gas mainly attributed to CH4, so bacterial material with Zeolite could reduce global warming gas emission from paddy field. There was significant increase in rice yield with the material. 47 | P a g e Short-term shifts in fungal community structure accompanying soil disturbance: observations from a six-month microcosm study Nicole Sukdeo, Ewing Teen, P. Michael Rutherford, Hugues B. Massicotte, Keith N. Egger University of Northern British Columbia, Natural Resources and Environmental Studies The arrangement of naturally-occurring soil horizons endows ecosystem functions that rely upon the integrity of soil structure and organic matter reservoirs. How soils continue or shift in their role as microbial habitats is an important consideration when soil profile disturbances are introduced on a large spatial scale, as is the case with pipeline right-of-way installations. The objective of our short-term microcosm study was to evaluate whether manipulations of the mineral soil/LFH interface results in fungal community structure differences over a six-month period. We created combinations of mechanically disrupted LFH and mineral soil layers from soil core samples collected from coastal western hemlock and sub-boreal spruce forests that were incubated under identical light/dark, temperature and humidity conditions in a growth chamber. Analysis of Illumina tag sequence data for the fungal ITS2 region indicated a pronounced shift, including controls cores, to Zygomycota-dominated fungal communities, consisting predominantly of operational taxonomic units belonging to the saprotrophic genus Mortierella. Abundant Basidiomycota reveal a predominance of ectomycorrhizal genera at T = 0 months with markedly reduced abundance at T = 6 months. This shift reflects the disruption of mycorrhizal structures, with the flourishing of Zygomycota likely related to nutrient availability from dying mycelium. We present this data along with profiles of soil litter decomposition activities and discuss their implications for soil handling/storage practices, in addition to insights on mechanical disturbance-associated changes in soil fungal diversity. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Carbon limitation constrains soil microbial activity and influences microbial community composition in soils under organic management Rhizospheric bacterial proteolytic communities under the influence of plants with different nitrogen uptake rates Divyashri Baraniya1, Edoardo Puglisi2, Maria Teresa Ceccherini1, Giacomo Pietramellara1, Laura Giagnoni1, Mariarita Arenella1, Paolo Nannipieri1, Giancarlo Renella1 Melissa Arcand, Bobbi Helgason Saskatoon Research Centre, AAFC Agricultural practices (e.g., tillage, fertilizer inputs) and crop rotation can influence soil organic matter (SOM) and soil microbial communities, which are the primary regulators of soil nutrient processes. Despite the importance of crop residue inputs to soil organic carbon balances and SOM formation, the role that microbial community composition plays in decomposition processes is not well understood. The objective of this study was to examine the influence of differing cropping systems on soil microbial community abundance and composition and its reciprocating effects on C utilization and residue decomposition. Soils under reduced-input conventional and organic management systems planted with a diversity of annual grain crops or with a mix of annual crops and three years of perennial alfalfa over six-year rotations were collected from a long-term (18 y) field study at Scott, SK. These soils were incubated with and without 13C-labelled barley residues in a 98 d laboratory study. Respiration rates were consistently higher in residueamended soils and in soils from the conventional compared to the organic system. Total microbial abundance and extracellular enzyme activities were highest in soils from the conventional-annual system, similar between the two perennial systems, and lowest for the organic-annual system. The pattern of 13C flow through the decomposer community over time differed between organic and conventional systems, highlighting the importance of management history in shaping microbial succession during decomposition. Decomposer community composition was correlated with soil respiration rates and enzyme activities. Results from this study indicate that microbial abundance and activities were lower and microbial community composition were different in soils under organic compared to reduced-input conventional management. However, residue amendment appeared to temporarily alleviate differences in community composition and activity among management systems—likely due to reduced C and nutrient limitation. 48 | P a g e 1 University of Florence, Agriculture and Environmental Sciences 2 Catholic University of the Sacred Heart, Microbiology & Agricultural Sciences Nitrogen utilizing efficiencies (NUE) of plants are an important factor that is governed by a complex interplay of various genetic and environmental factors. Recent studies highlighted the importance of extracellular microbial proteases in NUE (Mooshammer et al., 2014). Hitherto not much is investigated about the microbial proteolytic genes and sequences in soil. With present studies we have tried to get a picture of microbial proteolytic communities in rhizospheric soil under the influence of root exudates from plants differing in NUE. We have studied the microbial proteolytic communities in rhizosphere and bulk soil of two maize (Zea mais L.) in-bred lines L05 with high NUE and T250 with low NUE. Abundance of proteolytic microbial genes npr and apr have been studied using quantitative PCR and these were compared with the total proteolytic potential of the soil. To study diversity of these genes, amplicons were sequenced by Illumina high-throughput technology. Results indicate that high NUE cultivar is associated with both, higher proteolytic potential and a higher abundance of microbial genes for extracellular proteases, particularly rhizosphere is found to be rich in proteolytic genes. Analyses of several million apr and npr amplicons revealed a high diversity of proteases genes in soil and rhizosphere, with many sequences that are still unknown according to current sequences database information. We found that plant nitrogen metabolism and proteolytic potential of soil are directly or indirectly associated and bacterial proteolytic communities play an important role here. Furthermore, rhizosphere soil exhibits higher abundance of proteolytic bacteria, particularly Pseudomonas and Bacillus sp. This study provides useful information to improve the NUE of plants for global agronomic importance even at crop scale. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Genotype-specific variations shape the structure of root fungal communities and determine the response of chickpea to symbiotic fungi Navid Bazghaleh1, Chantal Hamel1, Yantai Gan1, Diane Knight2, Bunyamin Tar’an3 1 University of Saskatchewan, Semiarid Prairie Agricultural Research Centre 2 University of Saskatchewan, Soil Science 3 University of Saskatchewan, Plant Science The formation of root symbioses with soil microorganisms can impact plant growth and health. However, it is unclear whether variations in the symbiosis exist among plant genotypes and if they affect crop productivity. A 2-year field experiment was conducted in southwestern Saskatchewan, the central zone of the chickpea-growing region of the Canadian prairie. We tested the effects of 13 cultivars of chickpea, comprising a wide range of phenotypes and genotypes, on the structure of root-associated fungal communities, based on internal transcribed spacer (ITS) and 18S rRNA gene markers, using 454 amplicon pyrosequencing. We found genotype-specific variations in the structure of root-associated fungal communities and in the response of chickpea to arbuscular mycorrhizal (AM) fungi and non-AM fungal endophytes. Chickpea cultivar consistently influenced the structure of the root fungal community across years. The roots of cultivars CDC Corrine, CDC Cory, and CDC Anna hosted the highest fungal diversity and CDC Alma and CDC Xena the lowest. Fusarium sp. was dominant in chickpea roots but was less abundant in CDC Corrine than other cultivars. A bioassay showed that certain of these fungal taxa, including Fusarium species, can reduce the productivity of chickpea, whereas Trichoderma harzianum can increase chickpea productivity. A greenhouse study showed that fungal symbioses promote plant growth most effectively in CDC Cory, CDC Anna and CDC Frontier. Co-inoculation of AM and non-AM fungal endophytes had additive effects on CDC Corrine, CDC Anna and CDC Cory, but non-AM fungal endophytes reduced the positive effect of AM fungi on Amit and CDC Vanguard. The large variation in the profile of growth-promoting and -inhibiting species in chickpea roots, and in its response to symbiotic fungi support the possibility of selecting chickpea genotypes that associate with improved root mycota and form more efficient symbioses with soil fungal resources. 49 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S4: Organo-Mineral Interactions in Soil 50 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 1 2 Spatial distribution of soil organic matter across density fractions of soil day nanoparticles: STXM chemical mapping Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles Sofia Oufqir1, James Dynes2, Brandy Toner1, Paul Bloom1 Qiaoyun Huang1, Huayong Wu1, Wenli Chen1, Jeremy Fein2, Peng Cai1 University of Minnesota, Soil, Water and Climate University of Saskatchewan, Canadian Light Source Inc. The current research interest lies on the interactions between soil organic matter and clay minerals because of their important role in sustaining the fertility and tilth of soils. With this study we seek to provide original knowledge about the spatial distribution of soil organic matter across soil clay particles. Our goal was to probe the speciation and distribution of carbon and its association with aluminosilicate elements in density fractions of the whole soil clay (< 2 µm) and fine clay (< 0.2 µm) using scanning transmission x-ray microscopy (STXM). We isolated a surface soil from a mollisol in Southwest Minnesota from which we fractionated whole clay and fine clay samples. These fractions were then subjected to density separation combined with low energy ultrasonic dispersion to separate the free and physically protected organic matter. The results indicated an abundance of proteins, polysaccharides, and black carbon in the whole clay with proteins only in the light fraction and black carbon only in the light and the middle fractions. In contrast, only polysaccharides appeared in any of the three fine clay density fractions. Polysaccharides appear to be preferentially associated with the fine smectitic clays in this mollisol. Peptides are abundant in the whole clay, especially in the light fraction, they are not contained in the fine clay density fractions. Black carbon constitutes a major component of the light fraction of the whole clay, is scarcely present in the middle fraction and is totally absent in the fine clay density fractions. These findings clearly elucidated the nature and the fate of soil organic matter components associated with clay minerals in a mollisol soil. 51 | P a g e 1 Huazhong Agricultural University, Agricultural Microbiology University of Notre Dame, Civil and Environmental Engineering and Earth Sciences 2 Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of -3.0 ± 0.4 nN and -330 ± 43 aJ (10-18 J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Character of Organic Matter in Deep Soils of Temperate Forest Ecosystems Carmen Enid Martinez1, Michael Schmidt1, Aubrey Fine1, Joseph Dvorak2 1 Cornell University, Soil and Crop Sciences 2 Brookhaven National Laboratory, National Synchrotron Light Source Soil organic matter is found throughout soil profiles, with content typically decreasing from the surface to the bedrock. Despite this decrease in SOM content with depth, global estimates of soil organic carbon (684-724 Pg C at 0-30 cm and 1462-1548 Pg C at 0100 cm) and total soil nitrogen (63-67 Pg N at 0-30cm and 92-140 Pg N at 0-100 cm) suggest deep soils are the largest terrestrial C and N pool. Still, the majority of studies on the content and character of organic C and N have focused on surface soils, leaving the chemical forms and composition of SOM in subsoils in question. We employed coupled carbon and nitrogen x-ray absorption near edge structure (C-XANES and NXANES) spectroscopy and biomolecule (protein, DNA, chlorophyll) extraction methodologies to characterize the chemical structures of organic matter in profiles (0100 cm) from forest soils (an inceptisol and a spodosol) in central Pennsylvania. The XANES spectra of these forest soils reveal amide analogues (i.e., in proteins, chitin, nucleobases) predominate in litter layers whereas pyridine/ porphyrin analogues (i.e., heterocyclic C-N containing compounds) were dominant in mineral soils. Furthermore, within the mineral soil layers, we observed a consistent decrease in amide analogues and a consistent increase in pyridine/ porphyrin analogues with soil depth. This trend is consistent for all soil columns, except when an accumulation of particulate organic matter occurs in deep soil layers. Where organic matter accumulates the spectral features corresponding to phenolic-C, aliphatic-C, C in N-substituted aromatics, and C=N are more pronounced. Biomolecule extraction results are consistent with XANES analyses and show, in a pergram of carbon basis, an increase in DNA and protein and a decrease in chlorophyll content with soil depth. Our results indicate heterocyclic C-N containing compounds are likely to persist and accumulate at depth in terrestrial ecosystems as mineral-stabilized soil organic matter. 52 | P a g e Choice of extraction cocktail to remove contrasting proteins from reference soil minerals with a view to soil metaproteomic analysis Siobhan Staunton, Maguelone Nogaret, Laurie Amenc, Hervé Quiquampoix Institut National de la Researche Agronomique (INRA) UMR Eco & Sols Proteins are macromolecules with a strong tendency to adsorb strongly, quasi-irreversibly to various surfaces. The biogeochemical cycles of essential elements including C, N, P and S are largely controlled by soil proteins. Nevertheless soil proteins are poorly characterized. Various chemical extractants have been proposed to desorb proteins, including enzymes, from soils, but there are few data on the efficiency of extraction as a function of the protein characteristics and the mineral surface. This is one of the hurdles preventing the advance of the emerging field of soil metaproteomics. The aim of this study was to explore the experimental biases in the extraction of proteins from soil. This is the first systematic study of protein extraction. Six commercially available proteins with contrasting isoeletric points and molecular masses were adsorbed onto three reference soil minerals that differ in their specific surface area, surface charge and hydrophobic properties: montmorillonite, kaolinite and talc. Surface coverage and incubation period were varied. The extraction yields of four extraction cocktails differing in pH, buffer and presence of surfactant were compared. The extraction yields were low and mineral dependent. We shall discuss the best strategy for protein extraction from soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The role of temperature and soil texture in decomposition: findings from a physical fractionation study Amanda Diochon1, E.G. Gregorich2, B.H. Ellert3, H.H. Janzen3, B.B. Helgason4 1 Lakehead University, Geology Eastern Cereal and Oilseed Research Centre, AAFC 3 Lethbridge Research Centre, AAFC 4 Saskatoon Research Centre, AAFC Kinetic, Thermodynamic and Conformational Insights of BSA Adsorption onto Montmorillonite Revealed Using In-Situ ATRFTIR/2D-COS Michael Schmidt, Carmen Martinez Cornell University, Soil and Crop Sciences 2 Carbon dioxide produced during the decomposition of recently added plant residues accounts for most of the CO2 emitted annually from soils. The rate at which decomposition occurs is controlled primarily by climate (i.e., temperature and moisture) but factors such as soil texture and the chemical composition of the litter may also play a key role. As decomposition of an annual litter cohort proceeds, the quantity of residues remaining typically declines exponentially with time. During the process, residues are transformed, eventually becoming stabilized on mineral surfaces where they may persist for long periods of time. Soil organic matter fractionation is a useful tool for following the dynamics of residue decomposition in the soil. In this investigation we followed decomposition of isotopically enriched barley residues (13C, 10 atom %) mixed with soil at 9 sites across the agricultural regions of Canada, spanning a range of climate and soil properties. At each site, barley straw was applied at 200 kg C m-2 to soil microcosms (15 cm long, 10 cm diameter) inserted to a depth of 10 cm. All microcosms received additional unlabeled residue every fall (200 kg C m-2) and ammonium nitrate every spring (40 kg N ha1). Hourly soil temperature was logged throughout the year at each site and soil water content was also monitored during the frost-free period at one of the sites (Ottawa). Four replicate microcosms were removed from each site about 0, 0.5, 1.0, 2.0, and 3.0 years and the soils were physically separated on the basis of size into sand-, silt- and clay-sized fractions. The quantity of residues remaining in the sand fraction declined exponentially with time across all sites, with temperature explaining most of the variation. We did not observe a common trend in the dynamics of residue in the silt or clay fractions, which may reflect differences in mineralogy and/or organo-mineral interactions among the sites. These results indicate a shift in the key controls on decomposition as the process proceeds. 53 | P a g e Proteins in soils provide many functions essential to soil and environmental health. Cycling of contaminants, functioning of soil biota and nutrient dynamics are all influenced by soil proteins. Adsorption onto soil minerals may impact availability and activity of proteins and thus their functioning in soils. Adsorption of proteins onto mineral surfaces represents a dynamic interplay of kinetic, thermodynamic and structural factors, resulting in a complex adsorption mechanism. Coupled in-situ attenuated total reflectance infrared (ATR-FTIR) and two dimensional (2D-COS) spectroscopic analyses are implemented to address these factors in real time, revealing insights on the behavior of a model protein (bovine serum albumin (BSA)) at a model mineral (montmorillonite)/aqueous interface. Our results highlight a multistep kinetic process, with adsorptive controls limiting rates early in the process and diffusion of BSA to the interface controlling later. This shift in reaction kinetics is paralleled by transformations in BSA structure, showing conversion of α-helical secondary structure into disordered (random coils, extended chains and turns) and β structures during adsorption. Transitions between intermolecular and intramolecular β structures suggest reduction in surface crowding by BSA is of considerable importance. Adsorption isotherms follow the Langmuir model, yielding a μG of 30 kJ/mol. This value, taken with BSA structural changes and displacement of H2O evident in FTIR spectra, suggests an adsorption driven by a gain of BSA conformational entropy as well as dehydration of BSA and/or the montmorillonite surface. This work establishes a framework for future studies of protein behavior at mineral surfaces. These results also enhance our understanding of protein environmental chemistry, with implications including remediation and carbon stabilization in soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S5: Analytical and Methodological Advances in Soil Study 54 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The Structure, Associations and Interactions of Soil Organic Matter in-situ using Comprehensive Multiphase NMR Spectroscopy Andre Simpson, Myrna Simpson, Hussain Masoom Unbiased statistical analysis of soil 31P-NMR forms using compositional concept Dalel Abdi1, Barbara Cade-Menun2, Noura Ziadi1, Léon-Étienne Parent3 1 Soil and Crops Research and Development Centre, AAFC Semiarid Prairie Agricultural Research Centre, AAFC 3 Université Laval, Soils and Agri-Food Engineering 2 University of Toronto Nuclear magnetic resonance (NMR) spectroscopy has played a critical role in defining soil organic matter but traditional approaches remove key information such as the distribution of components at the soil-water interface and conformational information. Here a novel form of NMR with capabilities to study all components in all phases (solids, gels and liquids) termed Comprehensive Multiphase (CMP) NMR, is applied to study soil in its natural swollen-state. The key structural components in soil organic matter are identified along with their arrangement. The study identifies that the soil-water interface is dominated by carbohydrates and lipids while microbes and lignin are buried beneath the soil surface. The lipids are arranged with their polar heads towards the water and their tails are buried and may represent a conduit between the polar interface and more hydrophobic interior for organic contaminants. Lignin domains cannot be penetrated by aqueous solvents even at extreme pH indicating they are the most hydrophobic environment in soil and ideal for the sequestration of hydrophobic contaminants. Microbes are not exposed at the soil interface at neutral pH, but become more exposed at high pH and completely lysed in organic solvent. Finally the molecular interactions of hydrophobic organic contaminants in whole soil are considered. This includes monitoring kinetics, binding mechanisms and binding sites as the contaminant moves from the liquid state (post spill) to the fully sequestered state (true solid). CMP-NMR represents an extremely powerful approach for environmental research as it permits samples to be studied without extraction or drying and provides unprecedented molecular information on both structure and interactions in the native state. CMP-NMR spectroscopy will likely find widespread application not only in environmental research but also in fields such as medicine, biochemistry, biology, heterogeneous catalysis, or any other area that deal with samples containing more than one phase. 55 | P a g e Phosphorus (P) forms determined by 31P nuclear magnetic resonance spectroscopy (31P–NMR) are compositional data (i.e., parts of some whole bounded between 0 and the unit of measurement). Because compositional data are intrinsically related to each other within a closed pre-defined compositional space, a simple log transformation, variable by variable, or any other transformation of the compositional variables may produce statistically erroneous results. However, most studies analyze P forms as single components rather than parts of some whole such as total P (TP) or soil dry mass, leading systematically to methodological biases and conflicting interpretations. Compositional data analysis using centered log-ratio (clr) or isometric log-ratio (ilr) coordinates avoids such difficulties and preserves sub-compositional coherence in the analysis. The objective of this study was to compare classical and compositional methods for the statistical analysis of 31P–NMR P data expressed as proportions of TP or concentrations relative to soil dry mass. Two published datasets were used. Analyses of variance and regression analysis with soil pH were conducted on P species percentages scaled on TP or as untransformed concentrations scaled on a soil dryweight basis as well as their ordinary log, centred logratios (clr) and isometric log-ratios (ilr). Contradictory F-statistics values and coefficients of correlation with soil pH were obtained for the untransformed and ordinary log transformed 31P-NMR P data expressed as proportions or concentrations. In contrast, statistical results were the same regardless of the measurement unit when P compound percentages were clrtransformed. Using orthogonal ilr coordinates, 31PNMR P data were correlated to soil properties and to each other and synthesized into a multivariate distance without methodological bias. We conclude that the variance and regression analyses of molecular P species are scale-dependent and that the clr- and the ilr-transformations should be used to unbiasedly analyze the P fractions and avoid conflicting interpretations. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Integrated Light Element X-ray Excitation Emission Spectroscopy: Speciation, Diffraction, Quantitation in one soil analysis Determination of phthalates in soils and biosolids using accelerated solvent extraction coupled with SPE and GC-MS Adam Gillespie1, David Chevrier1, Teak Boyko1, James Dynes1, Tom Regier1, Derek Peak2 Kambiz Khosravi, Gordon Price Dalhousie University, Engineering & Agriculture 1 University of Saskatchewan, Canadian Light Source Inc. 2 University of Saskatchewan, Soil Science The stability of soil organic matter, nutrients and contaminants depends in part on the chemistry, environment and biology of a particular ecological system. Synchrotron-based X-ray spectroscopy is a useful and important tool to reveal chemical speciation of single elements in environmental samples. Depending on a particular system or research question, more information on multiple elements and/or mineralogy is typically sought. For example, a study on organomineral interactions may target carbon, aluminum, iron, and silicon chemistry, along with a separate mineralogical determination. Presented here is the development of a new synchrotron-based technique which allows simultaneous measurement of multiple elemental speciation, diffraction patterns, and total elemental amounts in a single analysis using a soft X-ray spectroscopy and energy resolving detectors. This method currently accesses the chemistry of most major macro-elements important to biological systems (C, N, O, P), major nutrient cations (K, Ca, Na, Mg), mineralogical components (Al, Si, Fe) and all first line transition metals (2p edges up to Selenium). For mineralogical and structural identification, soft X-rays used in this analysis can access d-spacings between 0.3 to 3 nm. This range covers the diagnostic basal spacings for many soil minerals. Finally, total elemental concentrations can be extracted using summed X-ray fluorescence across the entire X-ray excitation range. Together, this analytical tool has the potential to offer an analysis which integrates the chemistry of all important components of the soil system, including the chemical relationships between organic matter, cations, metals and minerals. 56 | P a g e A rapid highly sensitive method based on accelerated solvent extraction (ASE) coupled with solid phase extraction (SPE) and gas chromatography mass spectrometry (GS-MS) has been developed for the analysis of seven commonly identified phthalates found in soil and biosolids including: Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Benzylbutyl phthalate (BBP), Bis(2-diethyhexyl phthalate)(DEHP), Di-n-octyl phthalate (DnOP), Dipentyl phthalate(DPP) and Di-nbutyl phthalate (DnBP). Parameters for ASE were investigated to render maximum efficiency of phthalate recovery using a tri-solvent extraction (ethyl acetate, hexane, dichloromethane) in a 2:3:2 ratios along with different temperatures and static periods. A detailed oven program was developed for the GC-MS analysis in which seven major phthalates were separated. The results obtained for recovery of phthalates ranged from 85 to 111% in tests on field soils and an alkaline treated biosolid. The method was successfully validated for the SPE extraction efficiency and the loss of content. The optimized method resulted in high sensitivity of measurement with the LOD ranging from 0.03 ngkg -1 to 0.27 μgkg-1 and the LOQ ranging from 0.1 ngkg-1 to 0.87 μgkg-1 with the RSD ranging from 4.4 to 9.8%. Concentrations of phthalates recovered in an agricultural field soil ranged from0.03 ± 0.01 to 0.15 ± 0.04 ngg-1 but were measured at 0.63 ± 0.1 to 4.3 ± 0.48 ngg-1 in the same soil receiving an alkaline treated biosolid (ATB) amendment. The concentrations of phthalates found in the ATB used in the field soil ranged from 2.8 ± 0.81 to 8.3 ± 0.73 ngg-1, and the concentrations of phthalates in the raw untreated sewage solids (w/w) ranged from 3.4 ± 0.79 to 14.9 ± 1.3 ngg-1. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Propericiazine as a Selective and Sensitive Reagent for the Spectrophotometric Determination of Microgram Amounts Platinum in Minerals Comparison of in vitro estimates of bioaccessible Ni in field-contaminated soils and identification of mineralogy Luba Vasiluk1, Joanna Wragg2, Mark Cave2, Michael Dutton3 Ankapura Gowda Haranahalli Ramaswamy Institute of Higher Education 1 University of Guelph, Environmental Sciences British Geological Survey 3 Vale Ltd. 2 Propericiazine (PPC) is proposed as a new sensitive and selective reagent for the spectrophotometric determination of microgram amounts of platinum. PPC forms a pink complex with platinum (IV) at room temperature (26 + 20°C) in hydrochloric acid - sodium acetate buffer medium containing copper (II) ions. The complexation is complete within 10 min. The complex exhibits an absorption maximum at 520 nm with a molar absorptivity of 1.204 X 104 liters mol -1cm-1. Beer’s law is obeyed over the concentration range 0.5 - 12.2 ppm of platinum. A 50-fold molar excess of the chromogenic regent is necessary for the development of maximum colour Intensity. Job’s method of continuous variation, the molar ratio method, and the slope- ratio method indicate a 1:1 composition for the complex. The effects of pH, time, temperature, reagent concentration, order of addition of reagents and interference for various ions are reported. The reagent has been used successfully for the determination of platinum in minerals and alloys. Procedure: To an aliquot of the sample solution containing 12.5 – 305 µg of platinum (IV) were added 5 ml of hydrochloric acid- sodium acetate buffer of pH 2.1, 1 ml of 0.1M Cu(II) sulphate solution, and 3.0 ml of 0.5% propericiazine solution. The solution was diluted to 25 ml with distilled water, mixed thoroughly, and the absorbance measured at 520 nm against a reagent blank solution after 10 min. The platinum concentration of the sample solution was determined using a standard calibration curve. 57 | P a g e The bioaccessibility of a contaminant mixed with the soil matrix depends upon the soil properties, the contaminant and the manner by which the contaminant entered the soil. This study considers soil Ni contamination around smelting and refinery sites - the Vale complex in Sudbury (SUD) and Port Colborne (PC), ON, Canada. The objective was to determine a relationship among particle size, mineralogy and bioaccessibility. At each location, two naturally weathered soils were collected and separated into 2 fractions (150 – 250 μm and < 70 μm). Identifying the mineralogy was achieved with a non-specific sequential extraction CISED, SEM-EDS and XANES. Once the predominant minerals in the soil associated with Ni were identified, its relative chemical “solubility” was compared to the in vitro assay (PBET). In the SUD soils, the smaller particle fraction had the greatest [Ni]; in one soil the difference was 8 fold while the other 3 fold. Total [Ni] in PC soils were not different between the fractions, but were much higher than in SUD. The comparison of bioaccessible Ni and cumulative CISED extraction, showed that PC soils reached the PBET estimates at a lower nitric acid, while SUD soils required higher strength. Chemometric analysis identified the majority of Ni was co-eluted with high Ca soil component, suggests that it could be carbonate material in a humic acid exchangeable fraction or claylike matrix if Si is present. This material is the likely source of the bioaccessible fraction. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Approximating Soil Respiration and Belowground Biomass on the Qinghai-Tibet Plateau with Different Empirical Models Bosch1, Doerfer1, Anna Corina Jin-Sheng Karsten Schmidt1, Thomas Scholten1 Studying Natural Root Systems in Soil of the Semi-Arid Region of Brazil Rejane Pimentel1, Richard Heck1, Gabriela Almeida2 He2, 1 1 University of Tuebingen, Geosciences 2 Peking University, Ecology Soil respiration strongly interacts with climate change representing a significant process in global carbon dynamics. The release of carbon dioxide to the atmosphere accelerates global warming as well as global warming influences soil processes related to greenhouse gas emissions. The high, large and sensible Tibet Plateau is a key region for studying climate-induced soil processes. Soil respiration on the Tibet Plateau is fundamentally influenced by the amount of belowground biomass. For both, however, data are extremely scarce. The plateau´s large and complex terrain points to the need of predictive tools to derive estimates of root biomass and soil respiration for time and cost reasons. Various models have been developed to approximate them, often still requiring high-resolute, area-wide input data sets. Therefore, alternative approaches are necessary with less requirements concerning input variables. We applied different regression models developed from empirical studies with obtainable data sets for the input variables in order to find the most optimum available one to approximate belowground biomass and soil respiration at large scale on the Tibetan Plateau. Our comparison with field data shows that our results are consistent to other studies´ direct measurements. This allows us to provide a more accurate basis to the pixel-based, areawide estimation of root biomass and soil respiration on the Tibet Plateau with obtainable data sets. This so supports the assessment of potential greenhouse gas emissions on the Tibet Plateau, overcoming limited data at a large scale. 58 | P a g e 2 University of Guelph Universidade Federal Rural de Pernambuco Information relating interactions between soil structure and root system under natural conditions in semiarid environments are scarce, especially using X-ray microcomputed tomography (uCT). We investigate the segmentation of interface of soil structure and root system under natural conditions in the field. This study is been developed in soil covered with caatinga vegetation in Northeastern Brazil under two conditions, one preserved and another under restoration without anthropic actions for more than 50 years. Sampling occurred during dry season using acrylic tubes (7 cm high x 7 cm diameter) and digital images acquired with a Nikon XTH255ST CT scanner. Imaging processing was done in ImageJ ver. 1.49. Specifically, attention was given to segmentation air, mineral and root phases. Analysis is focused on quantification the morphology of the root system and associated soil pores. It was possible identify that the resolution used was efficient to distinguish the pore and solid phase easily. However, a third phase that seems to be a mix of pores and diminutive fragments of soil is under investigation. Root segments identified in the images were not segmented. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Permanganate-oxidizable carbon as a soil quality indicator in agricultural upland systems of Southeast Asia Impact of changes in sample preparation parameters (drying, grinding and sieving) on soil characterization of coarse-textured results in Quebec C. M. Hepp, T. B. Bruun & A. de Neergaard Hakima Chelabi1-2, Lotfi Khiari2, Jacques Guallichand2 Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen Land use intensification of agricultural upland systems is rapidly occurring in Southeast Asia. The sustainability of such transitional systems is questioned as (i) external inputs are minimal as farmers are resource-poor, and (ii) tropical soils are of inherent low quality. Soil carbon is often used as an indicator of soil quality as it relates to soil organic matter content (SOM) and thus to many biological, chemical and physical processes. The labile carbon fraction reflects the pool of SOM that is readily oxidizable, has a short turnover time and hence is sensitive to altered land use practices (Weil et al, 2003; Blair et al., 1995). In this study, the potential of permanganate-oxidizable carbon (Pox C), a measure of labile carbon, as a soil quality indicator was investigated in upland systems of Northern Lao P.D.R. Additionally, the influence of charcoal (Skjemstad et al., 2006) and Fe/Al (hydr-) oxides was investigated as it has been suggested that high contents of these parameters affect the validity of the method. Results show that Pox C is strongly correlated to total soil carbon. Both carbon parameters are correlated to the soil nutrients: Total N %, P Avail and K Exch; differences exist in the correlation strengths, supporting the claim that they represent different carbon pools. Regression analysis identified Pox C as an influencing factor for variations observed in upland rice yields. A clear relationship between land use intensity and Pox C was not defined; likely due to the field variation in biomass accumulation during fallow. Charcoal did not influence the validity of the permanganate oxidation method; the influence of Fe/Al (hydr-) oxides is currently still under investigation. Method inaccuracies are more likely due to inconsistent soil preparation or shaking and settling times. It is concluded however that Pox C is a suitable indicator of soil quality for tropical soils. 59 | P a g e 1 Agro-Enviro-Lab Université Laval, Département des Sols et de Génie Agroalimentaire, Faculté des Science de l’Agriculture et de l’Alimentation, 2 Routine analyses of characterization of agricultural soils in Quebec are usually made on soil samples either air-dried or oven-dried, crushed and sieved before being analyzed. A heterogeneous preparation of these samples could influence the results and therefore the recommendations of fertilizers and lime. The objective of this study is to evaluate the effect of the preparation techniques employed by five laboratories in Quebec on the homogeneity of the analysis results. In this experiment, a quantity of 8 kg of G3-texture soil (Sandy Loam, Beaurivage in Saint-Lambert, coordinated 46.63365 to 71.16191) taken from a depth of 20 cm was well homogenized, divided into 15 equal parts and sent to 5 different laboratories. Each laboratory had received three bags of about 500 g each. These samples were dried, ground and sieved according to routine procedures of preparation of each laboratory. Then, all 15 samples prepared were returned to a single laboratory to be analyzed in triplicate, for organic matter and exchangeable bases extracted by Mehlich-3 (K, Ca, Mg, and estimated CEC). The method of ANOVA nested structure has been applied to separate error terms. According to the results, the change in sample preparation procedures by different laboratories affects significantly the exchangeable bases (KM-III, CaM-III and MgM-III and the estimated CEC) and organic matter (loss on ignition). These five parameters showed variations both significant and superior to CEAEQ (2003) control limits or NAPT (2001). These errors reflect that these five characterization parameters are much less reproducible between laboratories (% error > 72%) than within the same laboratory (% error <9%). It is perhaps more appropriate to change the mechanical grinding parameters to obtain grading curves similar to those from a manual grinding mortar or ground (the technique of grinding research laboratories). Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Determination of the fixation sites of metal trace elements in lake sediments from taïga and toundra forest with a scanning electron microscope Melanie Aubin1, Maxime Paré1, Réjean Girard2 1 Université du Québec à Chicoutimi, Sciences Fondamentales 2 IOS Services Géoscientifiques Inc. Divers sites de fixation dans les sédiments de lac sont susceptibles de cumuler les éléments traces métalliques (ETM), tels que les oxydes et les hydroxydes de Fe et de Mn, la matière organique (MO), les argiles minéralogiques, les sulfures, les carbonates, etc. L’identification des ETM associés à chacun de ces sites de fixation à l’aide de méthodes analytiques non destructives, contrairement aux extractions séquentielles actuellement utilisées, pourrait permettre de mieux comprendre et de prédire leur dynamique de dispersion et de transformation biogéochimique dans les sédiments lacustres. Les objectifs de cette étude sont de : (i) identifier et quantifier les ETM (As, Co, Cu, Mg, Mn, Na, Ni, Pb, U et Zn) associés à chacun des sites de fixation dans des sédiments de lac; (ii) vérifier si les ETM associés à chacun des sites de fixation sont les mêmes entre les sédiments provenant de lacs situés dans la sous-zone de la taïga et dans la sous-zone de la toundra forestière; et (iii) comparer la signature géochimique obtenue avec celles préétablies à l’aide des résultats d’analyses partielle à l’aqua regia . Pour ce faire, un total de trente-six échantillons de sédiment ont été sélectionnés soient : trois échantillons de bassin versants différents et de même signature (diatomées, ferrochimique, MO, gyttja, détritique et silice) dont dixhuit provenant de la toundra forestière et dix-huit de la taïga. Les échantillons ont été soumis à des analyses au microscope électronique à balayage (MEB) muni d’un spectromètre à dispersion des énergies (EDSSDD), soit une méthode analytique non destructive. À l’aide du logiciel Aztec, des cartographies de distribution des éléments chimiques, couvrant la surface de chaque échantillon, ont permis de localiser les sites de fixation des divers ETM présents. La présentation traitera des résultats obtenus, c’est-à-dire un survol de la composition chimique des différentes signatures ainsi que des associations entre les sites de fixation des sédiments lacustres et certains ETM. 60 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S6: Agricultural Greenhouse Gas Emissions 61 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Farm-scale assessment of greenhouse gas mitigation strategies in dairy livestockcropping-systems Claudia Wagner-Riddle1, Kari Dunfield1, Craig Drury2, Robert Gordon1, John Lauzon1, Bill Van Heyst1, Andrew VanderZaag2 1 2 University of Guelph, Environmental Sciences Agriculture and Agri-Food Canada As a part of the Government of Canada's Agricultural Greenhouse Gases Program (AGGP), we initiated a study on greenhouse gas (GHG) mitigation strategies in dairy-cropping systems in fall 2011. Several projects are underway to examine GHG emissions associated with barns, manure management, and cropping systems management. Several measurement campaigns have been conducted at two commercial farms to quantify baseline emissions from two dairy barns, and the effect of diet manipulation. Results indicate a modest effect of 3.7% (P < 0.065) reduction in methane barn emissions when adding 30% corn dried distillers’ grains with solubles to the diet. For GHG emissions from manure storage, the mitigation practices evaluated were: (i) complete vs. partial emptying of the manure tank and (ii) anaerobic digestion. Complete emptying significantly reduced greenhouse gas emissions by 49% compared to partial emptying. Methane emissions from digestate were 80% lower than from stored untreated dairy manure during the first year of anaerobic digester operation. Soil emissions were quantified from agronomic studies using chambers as well as from field scale plots using micrometeorological methods. Factors studied were application timing (fall vs. spring), method (injected, surface applied and incorporated), manure treatment (raw vs. anaerobically digested) and crop type (annual vs. perennial) over 3 years. We will provide an overview of this project and highlight of results. 62 | P a g e Net ecosystem exchange of dairy cropping systems Muhammad Sulaiman, Claudia Wagner-Riddle, Shannon Brown School of Environmental Sciences, University of Guelph A better understanding of net ecosystem exchange (NEE) in annual and perennial cropping systems used in dairy production is needed for greenhouse gas emission model developments and life cycle analysis. A three-year study was initiated to determine the net CO2 fluxes from corn and hay, the two main feed crops used in dairy production. Two 4-ha plots were continuously monitored using the flux-gradient method deployed with a tunable diode laser trace gas analyzer and sonic anemometers. One plot consisted of a 5-year old hayfield and the other plot was planted in a continuous cycle corn from 2012 to 2014. All plots received dairy manure as fertilizer applied according to common practice. Average half-hourly daytime and nighttime NEE during the growing (May to October) and average half-hourly daily NEE during non-growing (January to April and November to December) season is presented. For corn during the growing season, daytime NEE (mean ± standard deviation) are -7.86 ± 0.41, -5.20 ± 0.45 and -5.74 ± 0.55 μmol CO2 m-2 s-1 while nighttime NEE are 3.16 ± 0.28, 3.49 ± 0.30 and 2.92 ± 0.34 μmol CO2 m-2 s-1 for years 2012, 2013 and 2014 respectively. During the non-growing season, daily NEE are 0.71 ± 0.41, 0.53 ± 0.43 and 0.82 ± 0.45 μmol CO2 m-2 s-1 for years 2012, 2013 and 2014 respectively. For hay during the growing season, daytime NEE are -6.14 ± 0.48, -7.58 ± 0.44 and -2.99 ± 0.44 μmol CO2 m-2 s-1 while nighttime NEE are 5.22 ± 0.29, 6.29 ± 0.29 and 3.21 ± 0.32 μmol CO2 m-2 s-1 for years 2012, 2013 and 2014 respectively. During the non-growing season, daily NEE are 0.31 ± 0.45, 0.44 ± 0.44 and 0.26 ± 0.45 μmol CO2 m-2 s-1 for years 2012, 2013 and 2014 respectively. Inter-annual variability of the NEE will be discussed in relation to biomass production, climatic conditions and crop physiological characteristics during each respective year. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effects of dairy manure management in annual and perennial cropping systems on N-cycling microbial community structure and associated in situ N2O fluxes Farm-Scale Estimation of C Sequestration and Greenhouse Gas Mitigation by White Spruce Shelterbelts: HOLOS, 3PG and CBMCFS3 simulations Karen Thompson, Elizabeth Bent, Shannon Brown, Diego Abalos, Claudia Wagner-Riddle, Kari Dunfield Chukwudi Amadi, Richard Farrell, Beyhan Amichev, Ken Van Rees University of Saskatchewan, Soil Science University of Guelph, School of Environmental Sciences Agricultural management, such as liquid dairy manure application and tillage, may affect soil microbial community functioning differently between perennial and annual cropping systems due to plant-specific characteristics influencing carbon and nitrogen inputs, potentially stimulating changes in microbial community structure. Nitrifying and denitrifying soil microbial communities are the major drivers of terrestrial N2O emissions and encompass a large range of functional diversity. Our objectives were to contrast changes in the population sizes and community structures of genes associated with nitrifier (amoA, crenamoA) and denitrifier (nirK, nirS, nosZ) communities in differently managed (liquid dairy manure application and tillage) annual or perennial fields demonstrating variation in N2O flux, and to determine if changes in N-cycling gene abundances or community structures were linked to levels of N2O flux. Continuous field-scale N2O fluxes were measured from 2012-2014 in a 2-ha springapplied liquid dairy manure hay/alfalfa (perennial) plot and two 2-ha corn (annual) treatments under fall (F) or spring (S) liquid dairy manure application. Soil was sampled in 2012 and in 2014; soil DNA was extracted and used to target N-cycling genes via qPCR (n=6) and for next-generation sequencing (Illumina Miseq) (n=3). Significantly higher field-scale N2O fluxes were observed in the corn plots compared to the perennial system, however, increased flux occurred after tillage in the perennial plot. Community composition ordinations indicated differences in N-cycling communities between annual and perennial cropping systems, and convergence of some N-cycling communities (notably nosZ) post-tillage. Shifts in Ncycling gene communities (size, or structure) demonstrated relationships with N2O flux in Mantel tests, and which communities demonstrated relationships varied between differently managed fields. Nitrifying and denitrifying soil bacterial communities are sensitive to agricultural management (annual vs. perennial crop type, liquid dairy manure management, and tillage) and communities will respond differently to variations in management, driving shifts in N2O fluxes. 63 | P a g e Shelterbelts have been reported to sequester atmospheric C in plant biomass and soil, reduce soil N2O emissions from adjacent crop lands and increase soil CH4 oxidation. The impact of five levels of white spruce (Picea glauca) shelterbelts (i.e. 0%, 0.3%, 0.6%, 0.9% and 1.2% shelterbelt to farm area ratio) planted at a spacing of 2 m, on the global warming potential (N2O, CH4 and C change) of a 688 ha model wheat farm cultivated for 60 years was simulated. HOLOS (i.e., a whole farm model based on Intergovernmental Panel on Climate Change methodology modified for Canadian conditions that considers all significant CH4, N2O and CO2 emissions from the farm) was used to calculate soil N2O fluxes. Data from the Physiological Principles in Predicting Growth (3PG) tree growth simulation model and the Carbon Budget Model of Canadian Forest Sector (CBM-CFS3), a carbon flux and stocks simulation model, was parameterized and validated for white spruce shelterbelts in Saskatchewan to simulate C additions in tree biomass and soil, respectively. Fertilizer N input to wheat field was 45 kg ha-1 yr-1 while N input to shelterbelt was a function of annual foliar and below ground biomass N concentration. Soil C change and CH4 flux in the wheat field were set to zero to reflect soil C equilibrium state after long term cultivation. Soil N2O and CH4 exchange in the ecotone area was modified to reflect a transition from the shelterbelt area to the cropped field. Cumulative total farm emissions after 60 years of cultivation decreased in the order 7483, 6677, 5871, 5066 and 4169 Mg CO2e, for 0%, 0.3%, 0.6%, 0.9% and 1.2% shelterbelt cover, respectively. An initial loss of soil C was compensated by biomass C associated with tree growth. Biomass and soil C accounted for 10 to 41% of decrease in cumulative total farm emissions. Reduced soil N2O as well as increased soil CH4 sink in shelterbelts accounted for 0.5 – 3.2 % of decrease in farm emissions. Shelterbelt planting therefore, may be a useful strategy for reducing greenhouse gas emissions associated with agricultural production. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Contribution of Soil N2O Emissions from Fall Alfalfa Plow-down in Organic Cropping Systems Nitrous oxide gas flux, emission factor and emission intensity following termination of perennial grass Megan Westphal1, Mario Tenuta1, Martin Entz2 Mayowa Adelekun, Wole Akinremi, Mario Tenuta University of Manitoba, Soil Science University of Manitoba, Plant Science University of Manitoba, Soil Science 1 2 Agriculture is the major contributor of soil N2O emissions due to nitrogen (N) additions, primarily from the use of synthetic and animal manure N sources. Perennial legumes (i.e. alfalfa) are used in organic cropping systems to provide N and other nutrients to the soil for subsequent crops. However, the amount of N2O emitted from the fall plow down of alfalfa in organic systems is not well understood. In this study, the Glenlea Long-Term Organic Crop Rotation Study near Winnipeg is used to monitor N2O emissions from the perennial alfalfa and wheat crop in the organic mixed forage system. In 2014 alfalfa and spring wheat which receives the alfalfa plow down phase of organic system were monitored as well as a conventional system comparison. The static vented chamber method was used to determine N2O emissions, soil conditions and agronomic measures were also obtained. Wheat spring N2O flux emissions were low with a maximum flux of 8.3 g N2O-N/ha/day. Plow down of alfalfa occurred in early fall. Flux data following the plow down showed minimal N2O emission episode with the peak flux of 0.52g N2O-N/ha/day occurring three days after the plow down. Field sampling followed until soil freeze up showing minimal emissions. Post thaw and spring until seeding (2015) emissions will be presented along with full crop year emissions from alfalfa and wheat that received the alfalfa plow down. 64 | P a g e Perennial forage grasses are efficient in utilizing soil nitrogen (N) and water; minimizing the loss of N to the environment. However, perennial forage grasses are often grown in rotation with annual crops. This study was conducted to compare the amount of N2O fluxes and plant available nitrogen (NH4+-N and NO3--N) in the surface (10 cm) soil from liquid pig manure (LPM) and solid pig manure (SPM) applied to soil cropped to canola (Brassica napus L), after timothy (Phleum pratense L.) and orchard grasses (Dactylis glomerata L.) were killed and ploughed down. The study was conducted at University of Manitoba Ian N. Morrison Research Farm in Carman, on a sandy loam soil, initially in a split-plot experimental design of two cropping systems (annual and perennial) as the main plots, and subplots of manure treatments (SPM, LPM and control). Each treatment was replicated four times. The perennial forage grasses were incorporated in the fall of 2012 and seeded to canola in the spring of 2013, the year of this study. Nitrous oxide fluxes were collected using static vented chamber technique from the canola on the annual-perennial rotation plot and the canola on the regular annual plot. The results showed that nitrous oxide flux was greater with canola on the recently terminated perennial forage than continuous annual cropping. The cumulative flux was 0.4, 3.8, 2.4 kg N2O-N/ha for the control, LPM and SPM on the annual-perennial rotation plots, respectively. The corresponding cumulative flux on the continuous annual plots, was 0.5, 1.2, 0.9 kg N2O-N/ha for the control, LPM and SPM, respectively. The differences in nitrous oxide fluxes between the cropping systems were due to the application of different amounts of available nitrogen. The emission factor and emission intensity of these treatments will be presented and discussed. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Silvopastures and trees increase the size and stability of carbon pools in agroforestry systems of western Canada Mark Baah-Acheamfour1, Scott Chang1, Edward Bork2. Cameron Carlyle2 Storage and stability of soil organic carbon under shelterbelt agroforestry systems Gurbir Singh Dhillon, Derek Peak, Ken Van Rees University of Saskatchewan 1 University of Alberta, Renewable Resources 2 University of Alberta, Agricultural, Food and Nutritional Science Agroforestry systems are common land-uses across Canada and could play a substantial role in sequestering carbon (C) as part of efforts to combat climate change. We studied the impact of component land-uses (forest vs. adjacent herbland) in three agroforestry systems (hedgerow, shelterbelt and silvopasture) on organic C distribution in three density fractions of soils at the 0-10 and 10-30 cm layers. The study evaluated 36 sites (12 hedgerows, 12 shelterbelts and 12 silvopastures) in Alberta, Canada, distributed along a soil/climate gradient of increasing moisture availability. At the 0-10 cm layer, total soil organic C (SOC) stock in the bulk soil was significantly greater in the silvopasture system (101) than in either the hedgerow (77) or shelterbelt systems (67 Mg C ha1). Soil organic C stock in both soil layers (0-10 and 1030 cm) was also significantly greater in forest (89 and 119 Mg C ha-1, respectively) than in adjacent herbaceous lands (76 and 77 Mg C ha-1). Across all sites, 31.5, 29.1, and 35.5% of SOC was found in the light fraction (<1.6 g cm-3), occluded fraction (ultrasonic dispersion at 360 W for 5 min, <1.6 g cm-3), and heavy fraction (>1.6 g cm-3) of soils, respectively. The largest pool of SOC in the more labile light fraction of the 0-10 cm layer was in the silvopasture system (50 Mg C ha 1), whereas the smallest labile light fraction component of SOC was in the shelterbelt system (17 Mg C ha -1). The largest pool of SOC in the more stable heavy fraction of both the 0-10 and 10-30 cm depth classes was in the shelterbelt (33 and 35 Mg C ha-1, respectively), while the least SOC was in the silvopasture system (26 and 20 Mg C ha-1, respectively). We conclude that the presence of silvopastures can increase total C storage in surface mineral soils, and that the establishment of shelterbelts in an otherwise annually cropped agricultural landscape enhances the size of the stable SOC pool. 65 | P a g e Implementation of agroforestry practices such as shelterbelt plantation is identified as one of the major strategies in the sequestration of carbon and reduction of greenhouse gases. Land management practices such as shelterbelt plantation also influence soil organic carbon (SOC) composition and stability due to changes in quality of litter input and microclimate. This study determines the potential of hardwood and conifer shelterbelts across the soil zones of Saskatchewan for belowground sequestration and stability of SOC at the farm landscape scale. We found that the average SOC content under the shelterbelts was significantly higher compared to the adjacent cultivated fields thus indicating that shelterbelt plantations can be an effective strategy for carbon sequestration. The average increase of SOC under the shelterbelts compared to fields ranged from 9-33 t ha-1. Tree density and age of shelterbelts, along with the amount of litter underneath the shelterbelts were the major factors affecting the amount of carbon sequestered. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy was used to study the effect of shelterbelt plantation on the composition and stability of SOC. The changes in speciation and stability of SOC were not consistent among the sites and were more strongly controlled by the site conditions compared to the shelterbelt management practices. However, an increase in the proportion of aliphatic C was observed under Scots pine (Pinus sylvestris) shelterbelts compared to hybrid poplar (Populus spp.) shelterbelts indicating that the litter biochemistry impacts the speciation of SOC under the shelterbelt. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of microirrigation type, N-source and mulching on nitrous oxide emissions in semi-arid climate: An assessment across two years in Merlot grape vineyard Managing fertilizer nitrogen application methods and N sources to improve crop performance and reduce ammonia volatilization and nitrous oxide emissions Mesfin M. Fentabil1, Craig F. Nichol1*, Gerry H. Neilsen2, Kirsten D. Hannam3, Denise Neilsen2, Tom A. Forge2, Melanie D. Jones3 Craig Drury, Xueming Yang, W. Dan Reynolds, Wayne Calder Agriculture and Agri-Food Canada 1 Department of Earth and Environmental Sciences and Physical Geography, University of British Columbia 2 Agriculture and Agri-food Canada, Pacific Agri-Food Research Centre, AAFC 3 Department of Biology, University of British Columbia Micro-irrigation, fertigation and mulching have been proposed to improve the nutrient and water-use efficiency of crop production. The effect of these management practices on the emission of nitrous oxide (N2O) from vineyards is not well understood and most prior studies were short-term (< 1 year). To investigate longer-term effects, a study was conducted in grape (Vitis vinifera L.; Merlot) planted in a sandy loam soil in British Columbia, Canada. The experiment was a factorial treatment design consisting of two microirrigation types (Drip or Micro-sprinkler), two nitrogen sources (surface applied Compost or fertigated Urea at a rate of 40kg N ha-1), and two vineyard floor managements (bark Mulch or “Clean” - meaning bare soil). Frequent measurements of N2O flux and soil and environmental variables were made over two complete years (2013 and 2014). A considerable portion (37% in 2013 and 61% in 2014) of the annual cumulative N 2O emission (∑N2O) occurred during the pre-growing season particularly within the thaw period. In 2013, the annual area-scaled ∑N2O emissions for Drip was ≈ 1.8 x Micro-sprinkler, Urea was ≈1.5 x Compost and Clean was ≈ 1.7 x Mulch. In 2014, ∑N2O emissions were over 14% higher, likely due to more freeze-thaw events, higher soil mineral N availability (47% higher), but treatments differences were not significantly different. Analysed over two-years, micro-sprinkler reduced growing season emissions by 41% and surface application of bark mulch decreased annual areascaled and yield-scaled ∑N2O emissions by 38% and 30%, respectively, suggesting bark mulch as a strategy for mitigating N2O emission. The observed interannual variability in the total N2O emissions suggests that at least a minimum of 2-yrs of continuous study may be required to estimate representative annual N2O emission budgets and to recommend N2O mitigation strategies in vineyard systems. 66 | P a g e In Canada, there were 4.2 million tonnes of N fertilizer products sold in 2010 at a cost of over $4.4 billion with urea and UAN representing 46% and 22.5% of all of the N fertilizer sales. A field study was conducted in 2013 and 2014 to evaluate the effect N fertilizer sources and additives (i.e. with/ without a urease inhibitor or with/without a urease and nitrification inhibitor) and N application methods (broadcasting, streaming or injection) on ammonia volatilization, nitrous oxide emissions and plant N uptake. Broadcasting urea resulted in the greatest ammonia volatilization losses followed by streaming and injection. There was 130 kg N/ha applied as a sidedress application when the corn was at the 6-8 leaf stage. On average, broadcast urea resulted in 60.4 kg N ha-1 loss, followed by streaming at 21.9 kg N ha-1 with injection having the lowest loss at 8.4 kg N ha-1. The addition of urease inhibitors decreased ammonium volatilization losses by 64% with broadcast urea, 26% with streaming and by 97% with injection. Injecting sidedress N fertilizers increased N uptake in both grain and total above-ground biomass compared to either broadcasting or streaming N fertilizers. The inclusion of inhibitors (urease with/without a nitrification inhibitor) resulted in greater yields and above-ground biomass than the control especially when the N fertilizer was broadcast or streamed. Nitrogen application methods were found to influence nitrogen losses from soils and the inclusion if inhibitors reduced losses and enhanced N uptake and crop yields. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S7: Chemical and Biological Controls on Organic P Cycling in Terrestrial and Aquatic Environments 67 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 On new opportunities and techniques for advancing the study of soil phosphorus Gross P mineralization and microbial P uptake in forage field soils along a soil test P gradient T.D. Fraser1, L.M. Condron2, P.M. Haygarth3 Kim Schneider1, Paul Voroney1, Derek Lynch2, Astrid Oberson3, Emmanuel Frossard3, Else Bünemann3 1 Colorado State University, USA Lincoln University, New Zealand 3 Lancaster University, UK 2 1 As soil scientists our understanding of phosphorus has always appeared to lag behind our knowledge of nitrogen and carbon, not least because of the complex chemical and biological processes involved. Here we use a meta-analysis and conceptual modelling approaches to refresh our (i) global perspectives and opportunities for phosphorus, with particular focus on the fate and transport of organic compounds and the relation to soil biodiversity. In doing this we shall also take stock of the armory of (ii) tools and techniques that are available. The high level drivers that have influenced our perspective have changed over the years. Phosphorus played a role as a macronutrient in plant and food production, particularly since the late 1940s. During the 1980-90s, the perspective shifted with the realization that phosphorus was being transferred to, and damaging, aquatic waters. Most recently in the 2000s, scares over long term security and access to global fertilizer supplies have shifted the perspective back to crop and food production. Although the importance of soil organisms has been acknowledged, the role of soil biodiversity in P transformations has received little attention with consideration for organisms at multiple trophic levels. There have also been changes in the types of tools available to soil scientists for studying soil phosphorus compounds. Original techniques used batch chemistry; thereafter nuclear magnetic resonance techniques, chromatographic separation and most recently molecular approaches have emerged. These techniques, combined with advances in nextgeneration sequencing of soil organisms, DNA barcoding and measures of function, present us with the opportunity to gain valuable insight into these complex relationships. We conclude that opportunities for studying phosphorus have never been greater, with food production, water quality and biodiversity all high on the agenda, combined with the emergence of molecular techniques for understanding soil chemistry and biology. 68 | P a g e University of Guelph, Environmental Sciences Dalhousie University, Plant and Animal Sciences 3 Swiss Federal Institute of Technology, Agricultural Sciences 2 Soil phosphorus (P) tests are indicators of plant available inorganic orthophosphate (Pi), but fail to account for Pi that may become available through biologically-driven processes of organic phosphorus (Po) mineralization. This P source may be especially important for crops in soils with low available Pi. In this experiment, gross Po mineralization and microbial P cycling rates were assessed using isotopic techniques in 4 calcareous soils having varying levels of Olsen soil test P. The soils were collected from dairy farm forage fields in Ontario, Canada. In an incubation experiment, rapid microbial 33P uptake was found for the soils with the lowest available Pi. Amounts of 33P incorporated into the hexanol-labile P pool (microbial biomass) ranged from 7 to 44% after 8 days and were significantly negatively correlated with water soluble Pi following a power type relationship. This suggests accelerated P cycling in the microbial biomass pool at solution P values < 0.1 mg P kg-1 soil, or about 4 mg P kg-1 Olsen P, as a result of biologically-induced P uptake. Daily gross Po mineralization rates ranged from 0.37 to 2.87 mg P kg-1 d-1 and contributed 11 to 58% of the isotopically-exchangeable P in 8 days (mean = 35%). Contrary to our hypothesis, no relationship was found between gross Po mineralization rates and available Pi concentrations. The results of this study suggest that Po mineralization has the potential to make a significant contribution to forage P nutrition, which would be of greater importance when available Pi is limiting. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Influence of soil pH and inorganic phosphate levels on glyphosate sorption Phosphorus containing water dispersible nanoparticles in arable soil Sirajum Munira1, Annemieke Farenhorst1, Don Flaten1, Cynthia Grant2 Xiaoqian Jiang1, Roland Bol1, Volker Nischwitz2, Nina Siebers1, Sabine Willbold2, Harry Vereecken1, Wulf Amelung1, Erwin Klumpp1 1 University of Manitoba, Soil Science Brandon Research Centre, AAFC 2 1 Institute of Bio- and Geosciences (IBG-3) Engineering, Electronics and Analytics (ZEA-3) 2 Glyphosate [N-(phosphonomethyl) glycine] is a broad spectrum, non-selective systemic, post-emergent herbicide. Glyphosate is the most widely used pesticide in western Canada. The objective of this study was to examine the competitive behaviour of inorganic phosphate (P) and glyphosate for sorption sites in soil. Soil samples were collected near Carman, Manitoba in 2013 from research plots that had received long-term field applications of P and Cd as chemical fertilizers. Treatments were plots with annual applications of monoammonium phosphate (MAP) at 20, 40 and 80 kg P ha-1 with Cd added at low, medium or high rates, and plots without annual P and Cd applications (control). A batch equilibrium sorption study was conducted in the laboratory to determine glyphosate sorption in soil under a range of scenarios. Results showed that glyphosate sorption decreased with increasing P levels under some of the pH conditions studied, regardless of whether P levels arose from long-term applications in the field, or from fresh applications in the laboratory. Analytical-grade glyphosate (typically used in scientific studies) showed similar results as a commerciallyavailable glyphosate formulation. Cadmium had no significant effect on glyphosate sorption. 69 | P a g e It is important to understand P-bonding in water dispersible nanoparticles for forecasting P dynamics and losses in agricultural systems. We hypothesized that water-dispersible P is detected as nanoparticles, in which Fe plays a crucial role for P binding. To test this, we isolated water-dispersible nanoparticles with average size about 180 nm from an arable topsoil (Haplic Luvisol, Germany), and assessed nanoparticulate P forms after field-flow fractionation (AF4UV-ICP-MS), with and without removal of amorphous and crystalline Fe-oxides with oxalate and dithionite, respectively. We found that nano-particulate P was present in two dominant sizes: (i) in complexes of organic matter and amorphous Fe (Al)-oxides in nanoparticles < 20 nm, and (ii) in aggregates of fine clay, organic matter and more crystalline Fe-oxides with a mean diameter of 170-225 nm. Solution 31Pnuclear magnetic resonance (NMR) spectra indicated that the organically-bound P predominantly comprised orthophosphate-monoesters. Approximately 65% of P in the nanoparticles was liberated after the removal of Fe-oxides (especially amorphous Fe-oxides). The remaining P was bound to larger-sized water dispersible nanoparticles and Fe bearing clays. Intriguingly, the removal of Fe by dithionite resulted in a disaggregation of the nanoparticles, evident in higher portions of organically-bound P in the < 20 nm nanoparticle fraction, and a widening of size distribution pattern in larger-sized nanoparticles fraction. We conclude that the crystalline Fe-oxides contributed to soil P sequestration by: (i) acting as cementing agents contributing to soil nanoparticles aggregation, and (ii) binding not only inorganic but also organic P in larger soil water dispersible nanoparticles. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Fate and transport of labile DNA- and Phospholipid-phosphorus through a grassland catchment transfer continuum Phosphorus of colloidal forest soil fractions as revealed by Field Flow Fractionation and liquid-state 31P-NMR Ying Wang, Ben Surridge, Philip M. Haygarth* Anna Missong1, Roland Bol1, Volker Nischwitz2, Sabine Willbod2, Jan Siemens3, Erwin Klumpp1 Lancaster University, Lancaster Environment Centre, UK 1 This paper focuses on the potential mobilization of DNA-phosphorus (DNA-P) and phospholipidphosphorus (PLD-P) from soil in a grassland catchment. DNA-P and PLD-P are among the most labile and biodegradable (and hence interesting) of organic phosphorus compounds. Our study was conducted to assess the flow of these compounds along the continuum from soils to surface flowing water pathways and ultimately into the stream water channel, in River Eden catchment in Cumbria, England. The aims of the study were to (i) quantify the magnitude of different P compounds, including DNA-P and PLD-P, in grassland agricultural soils, (ii) determine the forms and ranges of P compounds in surface and subsurface flow pathways (e.g. farmyard standing water, field gate area, field standing water, drain flow, spring and borehole water) under storm flow conditions; (iii) quantify the amounts of DNA-P and PLD-P in the water column and bed sediment of the River Eden. DNA-P represented between 5% and 17% of total soil P in the study areas; PLD-P accounted for less than 1%. The majority of the P exported through the various pathways under storm flow conditions was in particulate form, presenting 31 to 67% of total P. The proportions of DNA-P in total particulate P transported in these pathways ranged from 6% to 13%, and the proportions of PLD-P ranged from 1% to 2%. In the stream, DNA-P represented 5% to 16% and PLD-P presented 2% to 6% of the total particulate P. DNA-P and PLD-P also accounted for considerable proportions of total P in the stream bed sediment, ranging from 2 to 15%. These compounds could potentially be an important pool to support plant nutrition, as well as a potential contributor to P transfer and therefore water pollution risks. 70 | P a g e Research Centre Jülich, Bio- and Geosciences (IBG-3) Agrosphere 2 Research Centre Jülich, Engineering, Electroinics and Analytics 3 University of Bonn, Crop Science and Resource Conservation Environmental nanoparticles (diameter: 1-100 nm) and colloids (diameter: 100 nm- 1 µm) are the smallest natural particles in soils. Due to their surface charge and high specific surface area, they exert a decisive control on the mobility and bioavailability of strongly sorbing compounds, such as P. We investigated the fine colloids present in forest soils with the focus on the role of P in small particulate soil fraction. Therefore water dispersible colloids in a size range < 500 nm were extracted from field moist soil samples and analyzed by Field Flow Fractionation (FFF) and liquid state nuclear magnetic resonance spectroscopy (31P-NMR). The FFF technique coupled online to UV-, DLSdetector and inductively coupled plasma mass spectrometry (ICP-MS) enabled a size resolved characterization of the colloidal and nanoparticulate fractions and their elemental composition (Si, Fe, Al, P, Ca, Mn). To identify the different colloid associated P species, we performed liquid-state 31P-nucelar magnetic resonance (NMR) measurements on forest bulk soil extracts, on colloid extracts and on the electrolyte phase of their soil suspensions. The results confirmed that P is associated to the colloidal fraction of the forest soil (colloidal P). The types of nanoparticles and colloids present in the soil differ depending on soil origin and depth. The 31P-NMR spectra indicated that organic P are bound in, or sorbed to nanoparticles and colloids more strongly compared to inorganic P forms. Especially phosphate diesters were enriched in the colloidal fraction when compared to the total soil. The colloidal P-diester to monoester ratios were 2-3 times higher in the colloidal fraction. In contrast, relatively large percentages of inorganic P were found to be truly dissolved. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Temporal characterization of phosphorus forms, bioavailability, and mobility in Lake Champlain sediments Phosphorus Nanoparticles and Colloids of Forest Stream Waters – Fractionation and Potential Role in Ecosystems Courtney Giles1, Lydia Lee2, Elizabeth Rutila3, Peter Isles4, Yaoyang Xu3, Andrew Schroth3, Barbara Cade-Menun5, Jane Hill6, Gregory Druschel7 Nina Gottselig1, Thomas Meyn2, Volker Nischwitz3, Cynthia Halle2, Harry Vereecken1, Wulf Amelung1 Roland Bol1, Jan Siemens4, Erwin Klumpp1 1 James Hutton Institute University of Vermont, Geology 3 University of Vermont, Vermont Experimental Program to Stimulate Competitive Research 4 University of Vermont, Rubenstein School of Environment and Natural Resources 5 Agriculture and Agri-Food Canada 6 Dartmouth College, Thayer School of Engineering 7 Indiana University – Purdue University Indianapolis, Chemistry & Chemical Biology 2 Lake sediments represent a potentially significant source of phosphorus (P) in eutrophic waters. The organic P (Porg) fraction of sediments may become mobilized or hydrolyzed to orthophosphate during periods of high biological productivity or redox cycling; however, few studies have investigated the interseasonal or annual variability of these processes. We employed 31P NMR spectroscopy and enzymatic hydrolysis to assess the forms and latent bioavailability of Porg in sediments collected from a shallow eutrophic segment of Lake Champlain during multiple algal bloom stages and years (Missisquoi Bay, USA). In 2007-2008, bloom onset and peak bloom sediments contained the largest proportion of enzyme-labile-P, whereas pre- and post-bloom sediments were primarily composed of non-labile-P. Large proportions of monoester-P in detritus indicate the enrichment of P in surface sediments due to organic matter deposition. Multiple stereoisomeric forms of inositol hexakisphosphate (myo-, D-chiro-, neo-) in the sediments indicate in situ microbial epimerization or depositional processes from agricultural soils. Large proportions of enzyme-labile Porg corresponded to increased sediment P flux and the presence of reduced manganese and iron in pore water. In 2012-2013, bimonthly sampling revealed significant changes in the distribution of enzyme-labile Porg and reducible P and metals in surface sediments. Inter-seasonal changes in Porg may contribute to P mobility in sediments and important feedback dynamics between biological productivity and sediment-water-interface geochemistry. 71 | P a g e 1 Research Center Jülich, Insitute for Bio- and Geosciences (IBG-3), Agrosphere 2 Norwegian University of Science and Technology (NTNU), Hydraulic and Environmental Engineering 3 Research Center Jülich, Central Institute for Analytics (ZEA-3) 4 University of Bonn, INRES Soil Science and Soil Ecology Natural nanoparticles (NP, 1 - 100 nm) and fine colloids (FC, > 100 – 450 nm) have been assigned central roles in ecosystems due to the high relevance in global nutrient cycling. This is especially relevant for limiting nutrients such as phosphorus (P). Nanoparticles and fine colloids are important for the transport of phosphorus in aqueous phases and thus for the turnover of P containing nutrients in ecosystems. Small headwater catchments within undisturbed forest ecosystems provide stream water samples reflecting the natural load of nutrients and minerals cycled or released from the ecosystem. Through Field Flow Fractionation (FFF) coupled online to a multitude of detectors, the size resolved analysis of the NP and FC fraction is possible. Elemental concentrations in the fractions were recorded through an Inductively Coupled Plasma Mass-Spectrometer (ICP-MS) and through innovative measurements with an online Organic Carbon Detector (OCD). Single catchment NP and FC analysis has previously been performed. To continue on an upscaling approach, five streams in forest catchments were analyzed for the relevance of Fe, Al, Mn, Si and organic C for P binding in the particle fractions. Depending on fractionation, differing particle sizes preferentially containing P sorbed to metal (hydr)oxides and organic C can contribute substantially. Further, it is examined if the relevance of nanoparticles and fine colloids for P fluxes through stream water increases with decreasing easily available phosphorus content between the sites. This study has shown that a size dependent binding to different chemical compounds derived from soil or ecosystem components occurs. Further, sites that are classified as phosphate limited, have a higher binding of phosphorus in the nanoparticulate fractions of stream water samples than phosphate rich sites. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A comparison of phosphorus forms and concentrations in midden samples and forest soils from Calvert Island, BC arable soil Barbara Cade-Menun1, Paul Sanborn2, Farid Rahemtulla3, Myrna Simpson4, Corey Liu5 1 Semiarid Prairie Agriculture Research Centre, AAFC University of Northern British Columbia, Ecosystem Science & Management Program 3 University of Northern British Columbia, Anthropology 4 University of Toronto, Physical and Environmental Sciences 5 Stanford University, Magnetic Resonance 2 Long-term human habitation can alter nutrients and other soil characteristics, especially in buried sites such as middens. We compared soil samples from a large shell midden (waste disposal site) from Calvert Island, BC, in the traditional territory of the Heiltsuk and Wuikinuxv First Nations, to soils from the adjacent forest. The surface of the midden was > 300 years old, while deeper layers were > 5000 years old. Refuse in the midden reflects a coastal diet of clams, mussels, salmon, herring, sea lions and seals. Samples from the midden were collected at 1.75, 2.1, 3.0, and 4.3 m depths; samples in the two forest profiles included forest floor and mineral soil to 175 cm depth, sampled by horizon. Total phosphorus (P) ranged from 1540823745 mg kg-1 in the midden samples and 10-162 mg kg-1 in the forest soils. Total organic P was 11-27% of total P in the midden samples, increasing with depth, but was 11-81% of the forest soils, decreasing with depth. Fractionation showed P to be associated with calcium in the midden samples, and with aluminum and iron in the forest soils. And preliminary 31P-nuclear magnetic resonance (NMR) spectroscopy showed a greater range of P forms in forest soil samples than in the midden samples. These results suggest that buried middens can significantly alter nutrient cycling in forest soils. 72 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S8: Microbial Provision of Essential Services across Managed and Natural Ecosystems 73 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Interactions of ammonium oxidation pathways in soil environments from Southern China Apatite and orthoclase forest fertilization: insoluble phosphorus and potassium made available by ectomycorrhizal fungi and associated bacteria Chen Chen1, Shan Huang2, Xiaochun Peng1 Fontaine1, Paré2, Laurent David Nelson Thiffault3, J. André Fortin1, Yves Piché1 1 Université Laval, Sciences du Bois et de la Forêt Canadian Forest Service, Laurentian Forestry Center 3 Ministère des Forêts, Recherche Forestière 2 Most coniferous trees of the boreal forests are associated with ectomycorrhizal fungi. This association is responsible for supplying host trees with minerals and water while the fungal symbiont receives photosynthates. In the context of boreal forests, most of the mineral nutrients available to the ecosystem originate from bedrock weathering by ectomycorrhizal fungi and associated bacteria. This rock weathering is the result of soil microorganisms dissolving minerals by releasing organic acids and siderophores. The present study sought to investigate the value of apatite and orthoclase as phosphorus and potassium insoluble fertilizers in Picea glauca Moench (Voss) and Pinus banksiana Lamb. stands. Forest floors were amended with apatite and orthoclase at a rate of 650 and 900 g/m2 either separately or in combination. Changes in tree growth and nutrition were assessed with dendrometric measurements and foliar analyses. The contribution of selected microorganisms to the weathering of apatite and orthoclase has been tested in pure culture; we found both minerals to be readily used as P and K sources by common ectomycorrhizal species when no soluble sources were supplied. The presence of phosphate solubilizing bacteria in the mycorrhizosphere of Picea glauca Moench (Voss) has been confirmed. 74 | P a g e 1 South China Institute of Environmental Sciences Princeton University, Civil and Environmental Engineering 2 Ammonium oxidations are important pathways in soil environments. Various of ammonium oxidation pathways have been studied during last 20 years, including aerobic ammonium oxidation, anaerobic ammonium oxidation (anammox), ammonium oxidation by archaea (AOA), and ammonium oxidation coupling iron reduction (Feammox); however, our knowledge of the interaction of ammonium oxidations in soil environments are not adequate. Objectives of the study are 1) to investigate ammonium oxidation pathways in soil environments in Southern China because soil environments in this region have high ammonium concentration and low pH ; 2) to determine the interaction of ammonium oxidation microorganisms in different ecosystems; and 3) to investigate the linkage between the distribution of ammonium oxidation pathways and environmental factors. Soil samples were taken from subtropical forest, urban freshwater sediment, orchard, paddy and agroecosystem in Southern China. Main soil properties were measured, including soil moisture, pH, Fe content, nitrogen concentration (ammonium, nitrite, nitrate) and TOC. QPCR was used to quantify microbial abundance that responsible for ammonium oxidation, including ammonium oxidation bacteria (AOB), anammox bacteria, AOA, and Feammox bacteria. We hypothesize that 1) AOA and Feammox would have active abundance in soil environments in Southern China; and 2) pH and redox condition would be the key factors that affect the interaction of ammonium oxidation microorganisms. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The role of arbuscular mycorrhizal fungi in carbon cycle of agroecosystems The amplitude of soil freeze-thaw cycles influence temporal dynamics of N2O emissions and denitrifier transcriptional activity and community structure Francesca Scandellari, Elisabetta Tome, Massimo Tagliavini Free University of Bolzano Arbuscular mycorrhizal fungi (AMF), symbionts of many important crops, are known for their involvement in biogeochemical cycles, including that of carbon. In agroecological research this is of particular interest because AMF could contribute to boost the carbon sink capacity especially in long-term agricultural systems, therefore leaning toward the worldwide concern related to CO2 increase in atmosphere. In this work we present the results of studies carried in apple orchards and vineyards aiming at quantifying carbon allocation to AMF and their contribution to the emission of carbon dioxide (CO2) from the soil. We measured the degree of mycorrhization and soil respiration (Rsoil) as affected by different agricultural practices and we evaluated the contribution of mycorrhizal hyphae to CO2 emission. We also used strawberry plants labeled with 13CO2 in controlled conditions to measure the allocation of newly fixed C to AMF and to the plant structures. The results show that agricultural practices affect the degree of mycorrhization, although this remains relatively high even with disruptive techniques such as chemical soil sterilization, regaining the natural level within 3 years from treatment. Under controlled conditions plants allocate to roots roughly 6% and to AMF hyphae roughly 4% of the recently fixed C in 24 hours. Part of this is then released in the atmosphere through soil respiration. Roots and mycorrhizal hyphae together contribute to Rsoil 41-47% and we estimated that roots and hyphae almost equally contribute to Rsoil. Our research support the hypothesis that agricultural practices impact the mycorrhizal community and that this might affect the carbon balance of agricultural systems. These results consequently suggest the possibility to boost the natural presence of mycorrhizal inoculum by tuning the field management with the aim of fully exploiting natural resources of these systems. 75 | P a g e Claudia Goyer1, Sophie Wertz1, Bernie Zebarth1, David Burton2, Enrico Tatti1, Martin Chantigny3, Martin Filion4 1 Potato Research Centre, AAFC Dalhousie University, Environmental Sciences 3 Soil Crops Research and Development Centre, AAFC 4 Université de Moncton, Biology 2 In northern agricultural fields, a large proportion of the annual emissions of the greenhouse gas nitrous oxide (N2O) can occur during freeze-thaw (FT) cycles. Most studies investigating FT focused on the freezing temperatures and lengths but not on the thawing temperatures. The objective of the study was to determine the effects FT cycles of different amplitudes on N2O emissions, denitrifier transcriptional activity and the abundance and structure of the total and active denitrifier communities. Soil microcosms amended with NO3- (N) or NO3- plus red clover residues (N + RC) were subjected to freezing at -5°C followed by thawing at either +4°C or +15°C. N2O emission rates and the abundance and diversity of nirS and nirK genes and transcripts were measured immediately after soil thawing and 1, 2, 4 and 7 days after thawing. Peaks of N2O emission rates following FT were ~two fold greater in N + RC than N only amended soils. In N + RC amended soils, N2O emissions reached similar maximum rates (average of 29 μg N2O-N kg-1 dry soil h-1) under both FT based on the sampling points used, but was delayed by one day when thawing occurred at +4°C compared to +15°C. In general, the abundance of nirS and nirK denitrifiers were similar in N + RC and N soils. In N soils only, a lower abundance of nirS denitrifiers and nirS RNA:DNA ratio were observed under the -5°C/+4°C regime compared with 5°C/+15°C regime while nirK abundance and RNA:DNA ratio did not change significantly. Structures of the total and active nirS and nirK denitrifier communities varied with thawing temperatures and between N and N + RC amended soils. Results indicate that thawing at +4°C compared to +15°C led to a slower induction of denitrification and induced change in the diversity of nirS and nirK denitrifiers. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Influence of 4-Year Crop Rotations on the Structure and Function of the Root Endosphere Community and Performance of Wheat Borrell1,2, Historical Rotation ABC: changes in microbial community dynamics over 100 years of wheat production Bobbi Helgason1, Sarah Kuzmicz2, Henry Janzen3, Adam Gillespie4, Sean Hemmingsen5, Etienne Yergeau6, Charles Greer6, Jim Germida7, Peter Leinweber8 Hamel1,2, Adriana Navarro Chantal Yantai Gan1, Jim Germida2 1 2 Semiarid Prairie Agricultural Research Centre, AAFC University of Saskatchewan, Soil Science 1 Saskatoon Research Centre, AAFC University of Saskatchewan, Saskatchewan and Department of Food and Bioproduct Sciences, AAFC 3 Lethbridge Research Centre, AAFC 4 University of Saskatchewan, Canadian Light Source Inc. 5 The National Research Council, Saskatoon 6 The National Research Council, Montréal 7 University of Saskatchewan, Soil Science 8 University of Rostock 2 Crop rotation enhances agroecosystems performance, but it is unknown how different legume-cereal rotation systems may impact soil fungal communities and wheat productivity. In this study, (i) we determined the relative efficiency of eight legume-cereal rotation systems involving pea (PEA), lentil (LEN), chickpea (CHP) and wheat (WHT), based on wheat performance, and (ii) defined the influence of the eight crop rotation systems on plant-associated fungi. Wheat plant density was highest after PEA-WHT-WHT and LEN-WHT-LEN and lowest in the wheat monoculture. Wheat yield was highest after LEN-WHT-LEN and after PEA-WHT-PEA. Wheat monoculture was the least productive systems. Wheat seed carbon content was highest in the rotation PEA-WHT-LEN-WHT and lowest in CHP-WHT-WHT-WHT. Diversified rotations had higher levels of mycorrhizal root colonization in phase III (3-year) of the rotations as compared with rotations involving growing wheat on wheat. However, pyrosequencing results showed that the changes in the root-associated AM community were mainly driven by year/site of cultivation, whereas the non-AM fungal community was influenced by both, crop rotation sequence and year/site. The roots of wheat at anthesis in phase IV (4-year) of the rotations were similarly colonized by AM and non-AM fungi in all rotation systems and there was no crop rotation effect significantly affecting the fungal community composition, suggesting that wheat as host plant has a large effect on determining microbial community structure in the agroecosystems. 76 | P a g e The Lethbridge Rotation ABC Historical Plots were established in 1910 to evaluate the effect of fallow frequency on wheat yields. Beginning in 1967 plots were split to include N and P fertilizer treatments, providing a rare opportunity to examine soils which have undergone decades of adaptation to different management practices. Variation in fallow frequency (C input) and N fertilization revealed distinct microbial dynamics after 100 years of wheat production. Total biomass and functional group abundance in Nfertilized, continuously cropped soils were approximately twice that of soils which were fallowed every 3 years. Relative abundance of bacterial and archaeal ammonia oxidizers depended on the interaction of cropping frequency with N addition; denitrification functional genes nirK and nosZ varied only with cropping frequency. Further, high-throughput sequencing of bacteria, archaea, and fungi revealed diverse and distinct communities in the plantassociated bulk, rhizosphere, and endophytic communities among N and P fertilizer treatments. DNA recovery from archived soils was variable (8.2 – 28.4 μg g-1 soil; Fig. 2), but was not linearly related to sample age and all DNA profiles were relatively diverse. Soil organic matter analysis using PY-FIMS and XANES showed changes in organic N and C composition linking management, microbial dynamics and soil quality. The legacy of the Historical Rotation ABC experiment uniquely explores the long-term adaptation of microbial communities, lending insight into the effects of agronomic practices on agroecosystem sustainability. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Study of soil bacterial, fungal and microfauna diversity in potato agroecosystems using high throughput sequencing Jeanne1, Richard Hogue1, Thomas Jeanne1, Samuel Morissette2 Hogue1, Thomas Richard Nicolas Sanson2, Léon- Étienne Parent2 1 Institut de recherche et de développement en agroenvironnement (IRDA) 2 Université Laval In a study aiming to develop ecosystem services at farm level, two goals were targeted: to improve nutrient management in potato agro-ecosystems and to identify soil health and potato quality indicators. For this project, 16 sites located in 4 areas of the Province of Quebec were used. Each site was divided in 4 plots which were georeferenced in 2013 and 2014. The following crops rotation in a potato production system were evaluated: 1:1 (grain maize/ potato); 2:1 (oats/ raygrass/ potato; oats/mustard/potato and barley/oats/potato). These variables have been measured: yield, above-ground biomass, tuber quality, soil granulometry and porosity, pH, % O.M., macro and micro elements, microbial diversity (bacteria, fungi, microfauna) and quantification of nirF, nifH and amoA genes in the nitrogen cycle. Soil samples were collected at the flowering and maturing stages. Total DNA were extracted then PCR amplified with primers targeting the 16SrADN et 18SrADN areas. The resulting amplicons were sequenced using 2X300 pb reads strategy on a MiSeq Illumina plateform. Bioinformatics pipelines were used to treat the millions sequences obtained and enabled to accurately compare the microbial diversity of plots with the relative abundance of each microbial group and evaluated to identify diversity indices (Shannon; Choa1, Simpson), that can be connected to agronomic traits. The project continues in 2015 in order to complete the data base required for the meta-analysis used to identify soil health and potato quality indicators. 77 | P a g e Effect of four previous crops on potato yield and tuber quality and their impact on soil and rhizosphere bacterial community 1 Insititut de recherche et de développement en agroenvironnement (IRDA) 2 Agrinova We studied the effect of four previous crops (oat + clover; mustard; ryegrass; buckwheat) at three potato production sites. The objectives were to improve the potato yield and the tuber quality, and to evaluate the impact of each management system (rotation crop potato) on bacterial communities in soil and rhizosphere. Previous crops at sites B and C had no impact on potato yields. The highest potato yields were obtained at site B in buckwheat and oat + clover sub-plots. The highest yields obtained at sites A and C from the ryegrass sub-plots were almost similar to the lowest yield obtained at site B. The bacterial communities were extracted from soil and rhizosphere samples. Their DNA were extracted and amplified using primers targeting 16SrDNA V6-V8 region. The amplified products were analyzed by pyrosequencing. Based on rarefaction curves, richness bacterial index (RBI) values were calculated. Soil samples obtained higher RBI values. Previous crops showed lesser impact on RBI values than the sites. At site A, where the potato yields were the lowest, the previous crop had an impact on the richness of bacterial populations. Principal component analysis (PCoA) differentiated bacterial diversity settling in the soil and in the rhizophere, while relative abundance of several bacterial families, (Xanthomonadaceae; Flavobacteriaceae; Streptomycetaceae; Hyphomicrobiaceae; Chitinophagaceae; Oxalobacteraceae; Sphingobacteriaceae), could be putatively linked with few agronomic traits. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S9: Soil Science Education and Outreach 78 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Innovation and Creativity: Practical Application in Soil Science Field Courses Envirothon: Hands-on soils education for secondary schools students – a soils professional perspective Ken Van Rees Paul Hazlett University of Saskatchewan Where do innovative ideas come from? Are they random or systematic occurrences? Once you have a creative idea what do you do with it? Forget about it because it would be too difficult to see the idea through or do you step out of your comfort zone and give it a try. For those of us in educational environments what role does creativity have in our classroom or field activities and how do we incorporate these innovative ideas into our teaching? This talk will discuss the innovative ideas that have resulted from my experience to combine art with science. My innovation centered on trying to engage students in connecting with their environment through not only the traditional things we do in science whether in the lab or field but also with visual arts. For the last 10 years I have been examining different ways of incorporating art into my soil science field courses. For our undergraduate students in addition to the classical soil classification and tree mensuration techniques they are also incorporating drawings from the landscapes. It is hoped that this will provide students with another means of connecting with their environment, a more emotional attachment. Currently, students are painting the landscapes with acrylics and having the opportunity to be creative in their visual interpretation of the environment. Another aspect of incorporating art with soil science is the progress that we have made in learning how to create pigments from soils and using them to visually interpret landscapes. This process appears to be very appealing to students as it is more personal, organic and allows the students the freedom to be more creative. Natural Resources Canada, Canadian Forest Service, Great Lakes Forestry Center Envirothon is a secondary school team competition that focuses on forests, soils, wildlife, aquatic systems and human impacts on the environment. One unique aspect of Envirothon is that it is a practical, hands-on educational experience that teaches field techniques to develop critical thinking and problem solving skills. This approach exposes students to soil pits and profiles, and a broad array of experiential knowledge that cannot be taught in the classroom. A soils professional partnering with the Envirothon program has an excellent opportunity to influence students that are interested in environmental sciences but at a stage of uncertainty as to which specific discipline to pursue at college or university. This presentation will describe a first-hand experience of involvement with the Ontario Envirothon. It will outline the goals of partnering in terms of messages to impart and some of the techniques used to engage and excite students about soils in general, and about education and careers in soil science. Environthon: Hands-on soils education for secondary school students – a student perspective Lindsey Andronak Western Ag Innovations Envirothon is an annual hands-on environmental education competition that occurs across North America. Students from grades nine through twelve develop problem-solving skills, public speaking skills and the ability to work as a team while learning about current environmental issues. The competition is divided into two main parts: the trail test and the oral presentation. To prepare for both aspects students are encouraged to study educational material on four main topics: soils and land use, aquatic ecology, forestry and wildlife, along with a theme topic that changes every year. This presentation will focus on a general overview of Envirothon from a student perspective, with an emphasis on the soils and land use topic. Sample questions from previous Envirothon tests will be provided, so put on your thinking caps and see if you are smarter than a high school student! 79 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil Science Education for Non Soil Science Professionals Real life soil stories: an untapped resource Jane MacIntyre David Kroetsch1, Richard Heck2, Harold Lee3 Tyndale University College 1 Science and Technology Branch, AAFC 2 University of Guelph, Environmental Science 3 Ontario Ministry of Natural Resources and Forestry, Science and Research Branch There is a need to develop soil science education materials and programming to support the professional needs of environmental scientists, consultants and other non-soil trained users. The need to support pedology and soil landscape description and characterization skills and education for a broader community is evident and has been part of soil conferences over the last years. There is a requirement to describe and characterize soils as part of other projects. One such example is the teaching of a soils module as part of a larger Ecological Land Classification course presented by the Ontario Ministry of Natural Resources. When the course was being developed pedologists and ecologists defined what type of soil information needed to be collected and how this should be presented to complement and enhance the ecological concepts and methodologies. Soils are presented as the variable fundamental substrate upon which the vegetation responds with respect to soil moisture and nutrition. The development of a graduate diploma course in field soil inventory was identified as a priority for the School of Environmental Sciences, University of Guelph. It was determined that additional instruction in field pedological techniques was required for students in graduate programs to enhance and support collection of soil and soil landscape data for their thesis research. This course supports other students and professionals seeking to enhance their field soil and soil landscape description and characterization skills. It is important to develop the capacity to provide elements of soil science education to support a broad and diverse group of environmental and other professionals that have the requirement to describe and characterize soils in all parts of the landscape as part of their data collection activities. 80 | P a g e One of our science goals is to help our primary students become aware of the importance of soil. We want students to understand the properties and characteristics of soil so that they can use this knowledge to effectively care for soil. Unfortunately, with the present day emphasis on literacy and numeracy in our schools, science may be pushed to the background. To compensate for lack of time, science may be taught through a sterile textbook and children may begin to view science as a confusing jumble of irrelevant facts and unfamiliar vocabulary. To prepare our children for the environmental challenges they will face, they will need a strong, hands-on, inquiry-based science program. As science educators, the challenge is to find materials that will stimulate the imagination, inspire and motivate students to investigate scientific topics while at the same time building strong literacy skills. We want to start students on their journey into the world of soil investigation in a safe and engaging way and what better way to do this than through the use of stories. Throughout history people have passed down stories which have helped future generation learn concepts, values and strategies. The familiar story format would ease children into the sometimes unfamiliar world of soil science. As I asked people to share their own personal real-life soil stories, I discovered that these stories were a dynamic and powerful “untapped resource” for introducing children to the scientific knowledge, concepts and vocabulary found in the more formal soil activities and experiments. The stories serve as a bridge that would lead children into the scientific world in a non-threatening and familiar way. In this presentation I will examine the important role “bridging stories” may play in the development of soil concepts and vocabulary prior to beginning more formal science experiments. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 “La forêt m’invite”: A wild leek conservation project for high school students Planting Seeds of Knowledge in Soil. How to Get Children’s Hand (Scientifically) Dirty Claire Vasseur, Jocelyn Gagnon Jacynthe Masse Biodôme de Montréal University of British Columbia Presently, 81% of the population of Quebec is living in urban areas (statistic-Canada, 2011). Young people are less exposed to natural environment and some high school students have never been in the forest. Walking on smooth humus, breathing forest plants, observing the scale and diversity of trees, allows one to experience a sense of well-being and appreciate the contribution of forested areas. Future generations will protect what they know and love. Wild leek is an indigenous, slow growing, ephemeral spring plant, threatened by overharvesting in Quebec. Sowing wild leek is a way to raise awareness of students to local forest biodiversity and get them involved in conservation. Preliminary activities to spring field class involve sampling a maple forest soil and measuring acidity to determine if the site is appropriate for wild leek (pH 5-7). Students will prepare a virtual herbarium of spring wild leek companion plants in order to identify them in the spring and appreciate local understory diversity. Furthermore, they will be introduced to an experimental design, a seeding protocol and drawing a map of the seeding site. Involved students will see the fruit of their work after several years. The project is just beginning. So far, teachers appreciate that proposed activities are related to the academic program (habitat, ecological niche, tree identification, acidity, soil type and texture) and are integrated in a concrete experiment with a PBL (Problem-based learning) approach. Students enjoy manipulation and observation in nature which is the first step to awareness. When a child thinks about soil, what comes to its mind? Maybe dirt, mud, fertilizer, a garden? But is there something more to this brownish-coloured substrate beneath our feet? Of course there is! Once your eyes are opened to the wonders that lie beneath our feet, you see a rich, complex and vital ecosystem at the confluence of the biosphere, the hydrosphere and the atmosphere. During my PhD I wanted to be involved in environmental outreach activities. That's why I "outreached myself" to the UBC's Botanical Garden Education Coordinator. Together with the coordinators team we've developed an activity called "Subterraean life" on soil biodiversity. A few months following this enterprise, Evan's Lake summer camp contacted the Pacific Regional Society of Soil Science in order to help them develop educational soils activities. Once again, I've jumped on the train! Descriptions of the different activities developed for both organisms and rationale of why we should get involved, as grad students, with activities directly involving community will be discussed. I believe that getting the hands of children (scientifically) dirty is a great way to get precious allies for soils. 81 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S11: Wetland Soils in a Changing Climate 82 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Impacts of soil drainage conditions on soil heterotrophic respiration along a temperate agricultural hillslope transect Agricultural Surface Drainage and Changes in Soil Properties in Eastern Saskatchewan Robin Brown, Angela Bedard-Haughn Valérie Viaud, Emmanuel Tete, Pauline Buysse, Christophe Flechard Institut national de la recherche agronomique, UMR Hydromorphic minerals soils characterized by the alternation of water saturation and non-saturation conditions are the places of specific biogeochemical processes, and they play an important role in carbon cycle. Global warming is expected to affect soil water regime and its impact on soil heterotrophic respiration in these soils. This study aims at quantifying heterotrophic respiration at the annual scale, as affected by soil drainage conditions along an agricultural hillslope in a temperate oceanic climate. The studied hillslope is located in the Kervidy-Naizin headwater catchment (ORE AgrHys, France, 48°00’N 2°50 W). Soil CO2 efflux were measured about every seven to fifteen days from February 2013 to March 2015, using the dynamic closed chamber system Li-COR 8100A (Li-Cor, Lincoln, USA) in three locations contrasting by soil drainage conditions: (i) well-drained mineral soils in upslope position (WD), (ii) soils presenting transient saturation conditions in mid-slope position (MD), and (iii) poorly-drained mineral soils, which undergo continuous or periodic saturation and reduction conditions in downslope position (PD). The 9- m2 measurement sites were equipped for continuous measurement of soil water content (TDR probes) and soil temperature. The annual soil CO2 emissions were assessed with two empirical models using different moisture functions. Over the year, the soil CO2 efflux measured and predicted in WD was 2 to 5 times higher than in PD and MD, except in late summer. Annual CO2 emissions were 47% and 37% higher in WD compared to MD and PD, respectively, showing a significant reduction of soil respiration in poorly-drained conditions. The modeling approaches suggest that the range and magnitude of soil water content impact on soil CO2 efflux depends on soil drainage conditions. 83 | P a g e University of Saskatchewan Recent flooding of agricultural land in the northern and eastern Saskatchewan Prairies has resulted in increased agricultural drainage. Drainage is used to increase land available for farming, reduce costs associated with manoeuvring equipment around wetlands, allow for earlier seeding and improve growing conditions. Given that low-lying areas tend to have higher nutrient and organic matter concentrations than the surrounding uplands, drainage may create some of the best agricultural land. The aim of this study is to determine if agricultural drainage improves growing conditions and nutrient availability by measuring physical (i.e. structure and bulk density) and chemical properties (i.e. C, N and P). Sampling was completed in the fall of 2014 following harvest. Fortytwo wetlands were selected in the Prairie Pothole Region in the Black soil zone of Eastern Saskatchewan. The drainage age of wetlands ranged from 0 – 50 years. A corresponding midslope was sampled with each wetland. Intact cores were collected to a depth of 60 cm for analysis of bulk density, macronutrients and aggregate stability. Initial results suggest that drainage may change physical properties by increasing bulk density at the 0-15 cm depth. Drainage has also been found to increase the proportion of macroaggregates and decrease the proportion of microaggregates in drained soils compared to undrained soils. It is meaningful to understand how drainage affects key soil fertility related properties in order to determine if drainage is a suitable management practice for long term soil quality. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Assessing pedogenic controls on carbon mineralization, organic matter composition and microbial community dynamics in a mountain peatland Differences in CH4 production, storage and transport among plant community types during a wet summer at Mer Bleue bog, Ottawa Xiaoyue Wang1, Cherie Westbrooke2, Bobbi Helgason3, Angela Bedard-Haughn1 Elizabeth Cowan Carleton University 1 University of Saskatchewan, Soil Science 2 University of Saskatchewan, Geography and Planning 3 Saskatoon Research Centre, AAFC Peatlands in the Rocky Mountain area are usually formed on mineral sediments or developed with interbedded mineral lenses. Carbon (C) dynamics in peat are microbially driven and influenced by the chemical composition of organic matter. Our previous work showed that the presence and types of mineral horizons affect soil properties such as volumetric water content, pH, TOC and TN. Therefore our objectives were to examine whether the horizons present within soil profiles (i.e., horizonation) and their relative depths affect C mineralization and microbial community dynamics and to determine whether there are correlations among C cycling, microbial community and C composition. This research was conducted in Sibbald Research Wetland, a valley-bottom peatland drained by Bateman Creek in the Kananaskis area of Alberta. In this peatland 3 soil profile classes were identified according to soil profile horizonation and the types of mineral layers present: peat/mineral/calcareous sediment profiles (PMC), peat/mineral/peat profiles (PMP), and sedge peat/moss peat profiles (PP). Carbon mineralization was measured by incubation over 63 days. Microbial community composition and relative abundance were assessed using phospholipid fatty acid (PLFA) analysis. Carbon fractions were determined by water extractable organic C (WEOC) and Fourier transform infrared (FTIR) spectroscopy. Results indicated that relative depth had a greater effect than profile horizonation on C mineralization rate, microbial biomass and community structures. Only C mineralization rates were significantly affected by horizonation, whereas both C mineralization and microbial biomass decreased with depth. Compared with labile C fractions, microbial biomass was more correlated with C mineralization rates. This study contributes to our understanding of impacts of peat chemistry and microbial community dynamics on C mineralization, particularly in less-studied mountain peatlands with mineral horizons. 84 | P a g e The composition of the plant community, which reflects environmental variables such as nutrient availability and long-term water table depths, is often used as an indicator of the potential magnitude and spatial variations in methane (CH4) emissions among and within peatlands. The dominant vegetative communities of northern peatlands may also directly impact CH4 exchange by influencing substrate availability for methane-producing bacteria and gas transport above and below the water table via aerenchymous tissues, for example. To further investigate the relation between peatland vegetative community and CH4 production, storage and transport processes, we measured CH4 fluxes and their corresponding isotopic signatures (i.e. δ13C values) and collected pore water using sippers along depth profiles (< 50 cm, 50 cm, 65 cm, 80 cm) from June through mid-September, 2014, for three vegetative communities at the Mer Bleue bog in Ottawa. Mer Bleue is a relatively ‘dry’ peatland with a water table that is on average ~ 45 cm below the surface through the summer months. Annual methane emissions at Mer Bleue are estimated to be between 4 and 10 g C m-2 year-1 but with much greater emissions from sedge dominated plots. Pore water dissolved organic carbon and total dissolved nitrogen increased at all depths through the growing season as did the concentrations of CH4 at the 50 cm depth at most sites within all three vegetation communities. Redox potential and CH4 concentrations suggest that summer production of CH4 occurs below but close to the water table at Mer Bleue, in agreement with previous studies at Mer Bleue and elsewhere. Methane production, storage and transport processes will also be examined using flux measurements and isotopic analysis to evaluate the dominant methane production pathway and transport mechanisms. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Patterns of Microbial Enzyme Activity across Three Temperate Canadian Peatlands Andrew Pinsonneault, Tim Moore, Nigel Roulet McGill University Peatlands have accumulated vast stores of carbon over millennia but the projected impacts of anthropogenic climate change have the potential to reduce or even reverse carbon sequestration in these ecosystems. Microorganisms regulate key steps in biogeochemical cycles, such as the carbon cycle, through the production of specialized enzymes designed to break down organic matter for carbon and nutrients. However, there is a dearth of studies in Canada, a country rich in peatlands, touching upon the relationship between microbial enzyme activities and the abiotic characteristics of different peatland types. In this study, we report both spatial and temporal patterns of activity for a suite of key hydrolase enzymes and phenol oxidases along hydrological and pH gradients at three different field sites; a low pH ombrotrophic bog (pH=4.1), an ombrotrophic/minerotrophic peatland complex (pH=3.4 to 6.5), and a forested basin swamp (pH=6.2). Preliminary results suggest that both phenol oxidase activity (POA) and hydrolase enzyme activity (HEA) decreased significantly with depth and varied significantly with season (p<0.05) with summer and spring tending to yield the highest and lowest HEA respectively. At 10cm depth, temperature and pH were significant drivers of POA while, at 30 cm depth, temperature was the only significant driver. POA exhibited a negative relationship with phenolics concentration (PC; p<0.05) while PC was significantly and negatively correlated with HEA (p<0.05). These results suggest that the expected relationships of the enzyme-latch mechanism are evident across a range of Canadian peatland types and that increases in pH and/or peat temperature brought about by anthropogenic climate change could potentially increase POA, alleviate phenolic inhibition, and, consequently, mobilize peatland carbon stores through increased HEA. 85 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S12: Proximal Soil Sensing 86 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Enhancing Digital Elevation Models for Improved Soils Mapping Three-dimensional soil mapping using proximal soil sensors Shane Furze Asim Biswas1, Wenjun Ji2, Yakun Zhang1, Viacheslav Adamchuk2 University of New Brunswick 1 Soils are an essential component to both land and resource management, therefore, it is necessary to understand how physical and chemical soil attributes vary across landscapes within their geological, topographic, and hydrological settings. Currently, New Brunswick soils are spatially mapped as polygons depicting groupings of soil types with abrupt tessellated boundaries. These boundaries are based on topographic features resulting in large and crude delineations, thus limiting its applicability toward sitespecific resource operations. Due to its dependence on topography, these delineations are biased to any errors within the Digital Elevation Model (DEM) in which the topography was derived. Unfortunately, the existing N.B. DEM hosts two significant types of errors resulting in incorrect delineations of soil polygons. This project focuses on improving then combining already existing digital elevation layers such as, e.g., satellite generated data (Shuttle Radar Topography Mission (SRTM)), photo-grammetrically derived data (existing Provincial DEM), and traditional contour elevation data (Canadian Digital Elevation DEM (CDED)) through calibration with LiDAR-derived bare-earth elevation data sets to reduce the errors associated with the original digital elevation models. Next, pedotransfer functions and digital soil mapping techniques will be applied to the enhanced DEM to not only disaggregate existing soil maps but also derive hydrologically-corrected continuum maps of soil attributes at fine resolutions (1m2 to 100m2 grid size). The resulting maps will allow in-depth operation planning on a site-by-site basis. 87 | P a g e 2 McGill University, Natural Resource Sciences McGill University, Bioresource Engineering Optimal management of soil requires characterization of its properties and information on their spatial variability. This can be achieved through the creation of detailed and comprehensive maps that describe both the spatial and vertical variability of key soil properties. Proximal soil sensors can collect information on soil properties at high resolution in space within short time. However, data collection at depths often restrict to derive information in three-dimensions (3D). The purpose of this research is to test the feasibility of proximal soil sensors for mapping soil properties in 3D. A number of soil characteristics (optical reflectance, cone index and electrical conductivity) were measured at 154 locations continuously down to ~1.1 m depth (depending the soil thickness and rockiness) using Veris® P4000 probe from an 11 ha field in Macdonald campus of McGill University. Out of these sampling locations, 32 soil cores were collected and sampled at every 10 cm depth-wise for laboratory analysis. PLSR techniques were used to develop (using 24 soil columns) and validate (using 10 soil columns) spectral models comparing data from proximal soil sensors and laboratory measurement. Further, these models were used to predict soil properties at rest (122) of the locations. Soil properties (pH, EC, bulk density, organic matter) at each 10 cm of all 154 locations were fitted with depth functions to predict soil properties at 1 cm interval. Predicted soil properties were mapped horizontally at each 1 cm layer using geostatistical based krigging method. A Gaussian filter was used to determine the convolution kernel and join the 2D spatial maps at each cm depth to prepare 3D soil maps for the entire field. This research provided an improved methodology to map soil properties in 3D using proximally sensed data. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A Comparison of Machine Learning Techniques in Digital Soil Mapping for the Lower Fraser Valley, British Columbia Does Increasing Complexity of Tree-Based Classifiers Improve Prediction Results in Digital Soil Mapping? Brandon Heung1, Derrick Ho1, Jin Zhang1, Anders Knudby1, Chuck Bulmer2, Margaret Schmidt1 Jin Zhang1, Brandon Heung1, Derrick Ho1, Anders Knudby1, Chuck Bulmer2, Margaret Schmidt1 1 Simon Fraser University, Geography British Columbia Ministry of Forests Lands and Natural Resources 1 2 2 Machine-learning is defined as the (semi)-automated process of uncovering the patterns between large datasets using computer-based statistical models, where a fitted model may then be used for prediction purposes with new data. In soil science, machinelearning techniques have most commonly been used in the subfield of pedometrics for the development of digital soil maps due to developments in GIS, availability of spatial data, and advances in computer technology. Despite the growing number of machinelearning algorithms that have been developed, relatively few studies have provided a comparison of an array of different learners – typically, model comparison studies have been restricted to a comparison of only a few models. This study evaluates and compares a suite of 10 machine learners as classification algorithms for the prediction of soil taxonomic units in the Lower Fraser Valley. Here, a variety of machine learners (i.e. CART, bagged CART, Random Forest, k-nearest neighbour, nearest shrunken centroid, neural networks, multinomial logistic regression, logistic model trees, and support vector machines) were tested in the extraction of the complex relationships between soil taxonomic units (great groups and orders) from a conventional soil survey and a suite of 20 environmental covariates representing the topography, climate, and vegetation of the study area. The fitted models, which consist of the soil-environmental relationships, were then used to predict soil great groups and orders for the entire study area at a 100 m spatial resolution. The resulting maps were validated using 262 points from legacy soil data. Random forest resulted in the most accurate predictions with 58% and 71% accuracy for soil great groups and orders, respectively. This study provides one of the first comprehensive comparisons of machine learning techniques for classification purposes in soil science and may assist in model selection for digital soil mapping and geomorphic modeling studies in the future. In the subfield of pedometrics, the intersection of soil science and spatial statistics, tree-based decisionmaking algorithms are increasingly being used for the prediction of categorical soil variables over space. Tree-based learners all consist of nodes and leaves where a training dataset is partitioned at each node in order to achieve a maximize within-node homogeneity and between-node heterogeneity based on if-then splitting rules. With the numerous types of tree-based algorithms that have been developed, the Classification and Regression Tree model (CART) is the most well known in the machine-learning literature; however, subsequent to its development, techniques in ensemble-learning (the aggregation of multiple individual trees) and randomized variable selection have greatly increased the complexity of the original CART model. The objective of this study is to examine how the increase in model complexity, within the treebased family of classifiers, has influenced the prediction of soil categorical variables using a case study from the Lower Fraser Valley, British Columbia. Here, soil-environmental relationships were extracted, using CART, CART with bagging (ensemble learning), and Random Forest (ensemble learning + randomized variable selection) models, from conventional soil surveys and a set of environmental covariates that represent topography, climate, and vegetation. The extracted soil-environmental relationships were then used to predict soil great groups for un-surveyed locations of the study area at a 100 m spatial resolution and validated using legacy soil data from 262 pits. The baseline CART model resulted in an accuracy of 40%, the application of ensemble learning (CART with bagging) improved the accuracy by 18%, and the randomized variable selection had little effect. This is one of the first studies to draw attention to the relationship between model complexity and the prediction of soil variables. 88 | P a g e Simon Fraser University, Geography British Columbia Ministry of Forests Lands and Natural Resources Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Proximal sensors for site-specific fertilization: A case study in maize crops in Colombia Fabio Rodrigo Leiva, Ricardo Alfaro-Rodríguez Diagnosis of a drainage system based on GPR imagery in cranberry production Awa Mbodj, Diane Bulot, Jonathan Lafond, Christian Dupuis, Silvio Gumiere Universidad Nacional de Colombia Université Laval Recently there has been a growing interest in precision farming (PF) in Colombia, particularly regarding sitespecific fertilization (SSF) in order to improve fertilizer use efficiency and reduce negative environmental impacts. This requires identifying homogeneous management zones (HMZ) in the crop field, which is commonly made by intensive sampling that is costly and time consuming. Alternatively proximal sensors, that measure soil properties or crop characteristics near or in contact with soil/crop, can be used to assess quickly, reliably and inexpensively actual field variability. This paper is aimed at showing advances of a research carried out to evaluate proximal sensors of both soil and crop in order to promote the use of SSF in maize crops. A field experiment was undertaken in two commercial farms in Sabana de Bogotá (Colombia). Soil apparent electrical conductivity (ECa) was measured with a Geonics EM38-MK2 ground conductivity meter using transects spaced every 15 m across the field. Simultaneously, the soil water content (SWC) was measured with a TDR 300 meter (FieldScout) using a regular grid (15 m X 50 m). Data analysis included descriptive statistics, correlations and geostatistics by using SPSS 22 and ArcGIS 10.1 software. This allowed identifying three HMZ in which it was evaluated physicochemical soil properties (lab analysis), crop development by using a SPAD 502 chlorophyll meter, and maize yield (direct physical measurement, weighing). The comparison of the results obtained for the identified zones showed differences in the content and in the relationships between soil bases (K, Ca, Mg, Na), in the SWC and in the crop response at the two assessed farms. The outputs of this research point out that delimitation of HMZ by using proximal sensors may lead to improved fertilization management with clear economic and environmental benefits. The assessed proximal sensors have a significant potential to promote SSF in maize crops in Colombia. The optimal management of water resources is imperative both to increase the productivity of cranberry fields and to limit its environmental impact. It requires good governance of irrigation system but also a well-designed and fully functional drainage system. The causes of poor drainage are numerous ranging from poor design, to various discontinuities in the soil profile. To characterize physical and hydraulic soil properties, several conventional techniques are used depending on different spatial scales. Nevertheless, the measurements obtained by these techniques are point-shaped. They are practical at small scales, but too time-consuming to map the subsurface variability over larger areas. Also too close measurements could disturb the soil structure and induce errors. Largescale, remote sensing for estimating the water content in the first five centimeters from the ground to a minimum crop density; making it less suitable technique for agriculture. GPR is a good alternative to conventional diagnostic methods less suitable for the field and farm scales. It is a non-invasive geophysical method at high-resolution that uses electromagnetic energy. The objective of this work is to develop a diagnostic methodology of a drainage system based on ground penetrating radar measurements in cranberry culture and locate restrictive areas to the flow. To achieve this, an ongoing experiment is to characterize the subsurface topography of fields with the GPR using a 270 MHz antenna. After complete data processing, groundwater, soil horizons and drains can already be distinguished in the soil profile and a difference of drainage performance has been noted between through certain fields. 3D modeling at different depths in the soil can identify the highest reflectivity areas and characterize spatial variability into fields and relations have been found between 3D GPR maps and hydraulic conductivity at saturation maps. Another experience is the hydrogeological variability within the field. The temporal evolution of the water content has been followed on two transects and allowed to characterize the drawdown of the water table, to establish relations between GPR scans and tensiometers and TDR measurements simultaneously conducted and to detect defective drains. 89 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Defining the spatial heterogeneity of soil biological activity Statistical variability of soil test NO3-N and the management zone concept Viacheslav Adamchuk1, Nadiia AdamchukChala2, Jasmeen Kaur1, Joann Whalen3, Asim Biswas3 Alan Moulin1, Henry Wilson1, Xiaoyuan Geng2 1 2 Brandon Research Centre, AAFC Eastern Cereal and Oilseed Research Centre, AAFC 1 McGill University, Bioresource Ukrainian Research Institute of Microbiology and Virology of Zabolotnyi 3 McGill University, Natural Resource Sciences 2 Spatial soil heterogeneity is the major reason that crop fertilization needs change across agricultural landscapes. Differences in the soil attributes of importance for soil fertility have been linked to a number of natural soil forming processes as well as management history. Intensive, systematic soil sampling as well as proximal and remote sensing technologies have been the primary means of revealing spatial soil heterogeneity at any given point in time. So far, the soil properties of interest have been limited to physical and chemical. Non-uniform crop performance due to heterogeneous growing conditions has also been sensed at difference phases of production cycle. However, the relationship between physical and chemical soil attributes and crop performance is greatly affected by the microbiological activity in the rooting zone, which changes from location to location. The aim of this work is to emphasize the role of biological soil attributes in relation to the more conventional means of characterizing soil heterogeneity within an agricultural field. Twenty locations in three agricultural fields under alfalfa production were selected to represent areas with the diverse soil conditions in terms of landscape position and soil properties. Sets of biofilm (overcoat surfaces) were placed in each location to monitor the dynamics of six genera of diazotrophic bacteria and two phyla of fungi at the beginning of the growing season for a week-long period. Several cases of response of soil microbiology to local conditions were observed. 90 | P a g e Recommendations for fertilizer N in crop production and precision agriculture depend on statistical analyses of data which represent soil NO3-N fertility typical of management zones and fields. Non-normal distributions of soil test N are commonly log transformed prior to statistical analysis for interpolation with methods such as kriging, regression, or principle component analysis. These data are transformed to ensure that analyses meet the assumptions of normality and that the central moment represents the most representative values of soil NO3-N in the management zones. Analyses of soil test NO3-N in the 0-15 cm depth increment for samples (48 to 100 sites per field) in 8 fields in Manitoba identified a range of distributions including the lognormal, exponential, and Johnson lognormal. Mixed distributions consisting of 2 or 3 normal functions combined were also observed. No single distribution characterized soil NO3-N for all landforms or fields, and the distribution functions considerably. The consequences of this wide range of distributions are significant, as the calculation of moments such as the mean or standard deviation based on the normal distribution for untransformed data will result in biased estimates of parameters for soil properties. Appropriate analysis of soil test N0 3-N data representative of management zones is a key factor in variable management of fertilizer N. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S13: Spatial and Temporal Dynamics of Soil Processes and their Interactions at Multiple Scales to Study Complex Soil Systems 91 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Spatial and temporal variation in soil nitrogen supply in potato cropping systems in Prince Edward Island Spatial Variability of Soil Physical and Thermal Properties in Ituri Forest, Democratic Republic of Congo David Burton1, Kyra Stiles2, Bernie Zebarth3, Ryan Barrett4 Nsalambi Nkongolo1, Jean-Jacques Mbuyi Kakuni2, Michel Lokonda2, Floribert Budjo3, Jean-Remy Makana3, Corneille Ewango3 1 Dalhousie University PEI Department of Agriculture 3 Agriculture and Agri-Food Canada 4 PEI Potato Board 2 In Prince Edward Island potato production has been implicated as a major contributor to agricultural greenhouse gas emissions and the contamination of groundwater with nitrate. The use of the 4R management is being promoted as a means of reducing nitrogen impacts on the environment from arable cropping systems. One of the key elements in identifying the “right rate” of N fertilizer addition is a better quantification of the soil nitrogen supply (SNS). We have conducted (i) a temporal study of variation in SNS on six farms over the past 4 years, (ii) a study of the spatial variation in SNS in 25 potato cropping systems in PEI in the fall of 2014 and (iii) spatial and temporal variation in soils archived in the PEI soil quality archive over the past 17 years. The soil nitrogen supply test measures both the mineral nitrogen contained in the soil at the time of sampling as well as the nitrogen mineralized over a two-week aerobic incubation as an index of mineralizable nitrogen. We also examined the variation in proxy measures of nitrogen mineralization potential (No) in these samples. Temporal variation in mineralizable nitrogen was found to be less than the variation in mineral nitrogen. There was significant spatial variation in mineralizable nitrogen. These observations support the use of mineralizable nitrogen as an input in determining the “right rate” as part of a 4R nitrogen fertilizer program. 92 | P a g e 1 Lincoln University, Agriculture and Environmental Sciences Institute Facultaire des Sciences, Science du Sol et Eau 3 Centre de Formation et de Recherche en Conservation Forestière 2 Knowledge of soil physical and thermal properties is necessary to predict air, water and heat transport, flow and distribution. However, these properties are rarely measured especially in the tropics. We assessed of soil physical (bulk density, BD; air, VAC; water, VWC; total pore space, TPS; gas diffusion coefficient, Ds/Do; pore tortuosity, TOR) and thermal (thermal conductivity, K; resistivity, R; thermal diffusivity, D; soil temperature, T; volumetric heat capacity, C) properties at Lenda1Forest Dynamic Plot (FDP), Ituri Forest, Democratic Republic of Congo. Eighty soil samples were collected at 0.10 m depth in the middle of each 20 m x 20 m subplot inside the 10 ha FDP. Soil samples fresh weights were recorded, then samples were air-dried and brought to the laboratory for analysis of soil physical properties. Soil thermal properties were directly measured at these locations using a KD2 Pro Thermal Properties Meter. Soil moisture was measured with a Tetha Probe. The coordinates of each sampling location were recorded using global positioning system. Results showed that measured soil physical properties had less variability with coefficients of variation (CV) ranging from 8.41% to 26.54%. K, R, D and C showed large variability with CV up to 65.60%. Geostatistical analyses showed that all soil physical properties, except for WFPS and TOR, responded to exponential variogram models. The R2 ranged from 0.41 to 0.84. In addition, the range of spatial variability (A0) was the same (910.90 m) for most soil physical properties, suggesting that they can be sampled together at a same distance. For soil thermal properties, T, K, R and D were fitted to a Gaussian variogram model. A0 differed among thermal properties, but all had higher R2, suggesting that these properties had highly developed structure. More studies are needed in deeper soil horizons for a complete assessment of soil properties at Lenda1 FDP. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Spatial variation in soil bacterial communities in a commercial potato field Bernie Zebarth, Claudia Goyer, Sheng Li, Sean Whitney, Sara Neupane Mapping Temporal and Spatial Soil Hydrothermal and Mechanical Properties by way of the Soil Trafficability Prediction Model (STRAP) Marie-France Jones AAFC, Fredericton University of New Brunswick The variation in diversity of soil microbial communities within landscapes, and how this variation is affected by topographic features and soil properties, is poorly understood. To date, a primary limitation has been the availability of cost-effective tools to assess soil microbial diversity. Next generation sequencing now provides a practical means of characterizing soil microbial communities on large numbers of samples. Soil was collected from a transect approximately 1100 m long in a commercial potato field in New Brunswick. The transect included 83 sampling points, with distances between sampling locations varying from 2 to 50 m. The transect was located in a landscape with hummocky topography and with a range of elevation of approximately 24 m. Soil pH was variable, and ranged from 4.3 to 7.0. Soil texture was less variable with sand content ranging from 310 to 550 g/kg and clay content ranging from 85 to 175 g/kg. Most sampling locations were located in upper and mid-slope landscape elements. Slope at the sampling locations ranged from approximately 2 to 12%, and in many cases the direction of maximum slope was approximately perpendicular to the transect. A composite soil sample from 0-15 cm depth was collected from the potato hill at each sampling location late in the growing season and under relatively dry soil conditions. Diversity of soil communities were evaluated by sequencing the bacterial 16S rRNA genes using the Illumina miSeq system. Relationships between diversity of soil bacterial communities, topographic parameters (slope, curvature, aspect, elevation) and soil properties (soil pH, soil texture, soil organic carbon) were examined. Bacterial diversity at the phylum level was found to be primarily related to soil pH, and the spatial distribution of soil pH was related primarily with slope. 93 | P a g e The project deals with the integration of a temporal and spatial model to create an all-inclusive modeling tool to produce soil hydrothermal and forest operation risk maps. The approach taken is modular by connecting temporal hydrothermal processes dealing with soil wetting, drying, freezing, and thawing to spatially anticipated locations of dry versus wet soil drainage conditions. The temporal variations are modeled at daily resolution based on weather data (i.e. temperature and precipitation), and site specific watershed characteristics (i.e. altitude, slope, tree species composition, soil horizon) data via the Forest Hydrology Model (ForHyM). The spatial variations are derived from LiDAR-generated bare-ground elevation surfaces at 1 m resolution by way of a cartographic depth-to-water index (DTW), representing from very poorly drained (DTW < 10cm) to well drained (DTW > 100cm) locations. This project utilizes outputs from ForHyM as primary inputs for the Soil Trafficability Prediction (STRAP) model created in ModelBuilder to allow for geospatial forecasting based on specific soil conditions over time. Case study preliminary results focus on North-Western and Central New Brunswick comparing model results with sensor data collected from forest operations machinery and field plot surveys. The machine sensor and field data are used to calibrate STRAP in order to generalize the methodology for weather-dependent and geospatially based forecasting of soil conditions to better enable forest operation planning as seasons change from dry to wet and from wet to dry and from year to year. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The impacts of changing rangeland into forest park on availability of heavy metals Scale-variability of surface microtopography on a highly-stable soil under simulated rainfall Ebrahim Mahmoudabadi1, Asim Biswas2* and Alireza Karimi Karouyeh1 Edison Aparecido Mome Filho1, Richard Heck2, Daniel Giménez3, Miguel Cooper1 1 Department of Soil Science, Faculty of Agriculture, Ferdowsi University of Mashhad 2 Department of Natural Resource Sciences, McGill University Soil pollution with heavy metals is an ever growing concern due to the potential threat to food safety and detrimental effects on human and animal health. The uptake of metals by plants and ingestion by humans depends on their bioavailability in soil. Since landuse has tremendous influence on soil properties, it can also affect the availability of heavy metals. In order to assess the effect of changing landuse on bioavailability of Cu, Mn, Fe and Zn, a total of 116 surface soil samples were collected from three landuses: rangeland (RL), needle leaf (NL) and broad leaf (BL) forest (all land uses were under rangeland before 1966). The available (DTPA extractable) and total Cu, Mn, Fe and Zn concentrations, pH, organic matter, calcium carbonate and soil texture were measured using standard methods. Statistical analyses (e.g. correlation and ANOVA) indicated a significant difference in available form of all heavy metal (Cu, Mn and Zn) concentrations except Fe among the landuses. Soil organic matter was greatly influenced by the landuse type. A positive correlation between available form of heavy metals (especially Zn) and organic matter was also observed. Spatial distribution (determined using geostatistical methods) of available Cu and Mn was very similar within the region. Availability of these two elements was mainly affected by the amount of calcium carbonate present within the region. In contrast, available Zn showed a different spatial distribution and its availability was mostly under the influence of soil organic matter. Availability of Fe was affected by the amount of calcium carbonate and soil organic matter present within the study area. Information on the spatial distribution of heavy metals as influenced by soil properties which in turn controlled by landuses is important in understanding the extent and severity of soil pollution and its potential impacts in the converted parklands. 94 | P a g e 1 University of São Paulo University of Guelph 3 Rutgers University 2 Soil roughness depends on extrinsic and intrinsic factors that influence structural organization at the soil surface and it contains information on scale organization of processes such as clod fragmentation, runoff, sedimentation, and crust formation. Our objective was to evaluate changes of soil surface roughness with rainfall using a multifractal approach. After a disc plow operation on a Rhodic Kandiudalf, 20 plots (1 m2) were established. Rainfall was applied at an intensity of 120 mm h-1 in quintuplicate plots at amounts of 0, 40, 80, and 120 mm. After a 24 h drying period, elevation data of the plots was collected in a regular grid with a laser microrelief meter with 10 mm resolution. Two undisturbed soil blocks (12 x 12 x 5 cm) were collected from each plot and one was scanned with a multistripe laser triangulation (MLT) scanner resulting in an irregular grid. Field and block elevation grids were converted to gray-level images at resolutions of 100 and 200 pixel2, respectively. Multifractal f(α) spectra were calculated using a boxcounting technique applied to the images. The variance of the elevations (mm2) at field scale decreased linearly with rainfall from 116.62 at no-rain to 63.37 after 120 mm (R2=0.992), but there was no clear trend at the block scale. Although there were visual differences in f(α) spectra of individual plots, multifractal parameters were not different (P>0.05) across rainfall amounts at either scale. The shape of f(α) was effected by scale, with the f(α) from the blocks being more asymmetric (P=0.06) and narrower (P<0.001) than from those from the field. The sensitivity of the f(α) spectra to rainfall amount may be enhanced by a technique taking into account all the elevation points in the mesh and their distances. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Scaling mineral nitrogen dynamics by soil aggregate size Gordon Price, A. Georgallas. David Burton, Weixi Shu Dalhousie University, Agriculture A scaling model is used to describe the dependence of N mineralization on soil aggregate size. In the model the soil aggregates are treated particles with a welldefined radius of gyration and a non-fractal surface geometry. It is conjectured that the biophysical processes which result in N mineralization may occur at three different loci. The first is that these processes occur predominantly at the surfaces of the soil aggregates. In this case the model predicts that a plot of ln(N mineralization rate) vs ln(aggregate diameter) should be linear with a slope of -1. In the second, N mineralization occurs predominantly in the body (volume) of the aggregates. In this case, the model predicts a slope of 0. The third is that mineralization cannot be simply localized in this way and could occur anywhere, including the interstitial spaces between the aggregates. Here the model predicts the plot would be non-linear. A temperature controlled soil incubation, with two differently textured agricultural soils, was established to measure mineralized carbon and soil mineral N (NH4 and NO3) over a 100 day period from soil aggregates ranging in size from 1 to 2 mm, 2 to 4 mm, and > 4 mm. 95 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S14: General Soil Science 96 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 25th Anniversary (1990-2015) Findings from the Lethbridge Simulated Erosion Study Francis Larney1, Henry Janzen1, Andrew Olson1, Barry Olson2 1 2 Agriculture and Agri-Food Canada Alberta Agriculture & Rural Development Spring 2015 marks 25 years since the establishment of simulated erosion plots in southern Alberta. A skilled operator with an excavator stripped topsoil to simulate erosion to four depths (5, 10, 15, 20 cm cuts), which were compared to a control (0 cm cut). Four, one-time amendment sub-treatments (in 1990 only) were established on each of the cuts: fertilizer (75 kg ha -1 N, 22 kg ha-1 P), topsoil (5 cm re-applied), manure (75 Mg ha-1 wet wt. feedlot manure), and check (no amendment). Twenty-five years later, two of four original sites remain intact. The Lethbridge Dryland site has accumulated 25 growing seasons (1990-2014 inclusive) with wheat yield data from 24 (2004 being fallowed). In many of the early years, there was a cut x amendment interaction on wheat yield. This interaction was largely explained by the lack of a cut effect on plots amended with manure, compared to topsoil addition, fertilizer, or check treatments. With time, the efficacy of manure in restoring soil productivity declined. Nonetheless, in 2014, there was still a significant yield advantage (12% averaged among all cuts) from manure applied in 1990. Averaged for 25 growing seasons, the yield loss was 45 kg ha-1 cm-1 erosion yr1 for the check sub-treatment (no amendment). The amendments mitigated losses to 39 kg ha -1 cm-1 yr-1 (fertilizer), 29 kg ha-1 cm-1 yr-1 (topsoil), and 22 kg ha-1 cm-1 yr-1 (manure). The Lethbridge simulated erosion study continues to provide important information on soil productivity following catastrophic soil loss and the longevity of one-time soil amendments. 97 | P a g e Seeding various types of cover crops to winter wheat stubble in southwestern Ontario Xueming Yang, W.D. Reynolds, C.F. Drury, J.Y. Yang Greenhouse and Processing Crops Research Centre, AAFC Cover crop is becoming popular in the Midwest USA, as well as in Canada recent years. Planting cover crop in the fallow period after winter wheat harvest would benefit soil health and improved soil quality (particularly enhanced soil nitrogen nutrient) may further benefit corn production in following year. However, the effects of cover crop on nitrogen fixation or accumulation in biomass strongly depend upon how the cover crop is established and developed and how long it grows. To test this variability, various types of cover crops have been seeded to a Brookston clay loam and a Harrow Sandy Loam in SW Ontario in early- to mid-August after winter wheat harvest. Cover crops include common used red clover, crimson clover and hairy vetch, newly emerging nitro radish, and rarely used phacelia and sasbenia. Preliminary results showed that (i) sasbenia and phacelia were not performed well on both soils but nitro radish and commonly used type cover crops established and grew well, (ii) cover crops grew better on sandy loam than on clay loam soils and (iii) nitro radish can well inter-cropped with clovers and hairy vetch. The preliminary results also showed that nitro radish can scavenge large amount of N (up to 220 kg N ha-1) in the late fall when the radish biomass was collected at the first killing frost. However, Nitro radish very quickly decayed in following spring, leaving no radish residues visible from the soil surface in early April about a month before seeding corn in the region and such no sign of nitrogen beneficial to the subsequent corn related to the non-cover crop check. Since nitro radish had scavenged significant amount of nitrogen in fall and this nitrogen did not increase succeeding corn yield, we speculate that the nitrogen being held with nitro radish in fall was released from the soil in following spring, and this is worthy of further study. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Tile drains as modifiers of source and transport factors for nutrient exports from agricultural fields Prediction of hydrophysical properties of soils for sustainable land management in DR Congo Keith Reid, Tiequan Zhang, Keith Fuller Yves-Dady Botula1, Attila Nemes2, Jan De Pue3, Paul Mafuka1, Eric Van Ranst4, Wim Cornelis3 Agriculture & Agri-Food Canada 1 The systematic installation of tile drainage systems on agricultural land has long been recognized as a practice for improving the productivity of poorly and imperfectly drained soils. These systems however, are increasingly being viewed as an avenue for the export of nutrients and other contaminants to surface water bodies. In addition, very little attention has been given to the mechanisms by which nutrients are transported from the soil surface to the tile drains as well as the impact of the specific transport pathway on the risk of loss of different nutrients under varying conditions of soil type, soil and nutrient management practices and climate. Using field data from Nova Scotia and Ontario, the authors will discuss the transport pathways for dissolved P, particulate P and nitrate-N through the drainage zone, and the impact thereof on nutrient management practices. 98 | P a g e University of Kinshasa, Natural Resources Management Norwegian Institute for Agricultural and Environmental Research 3 Ghent University, Soil Management 4 Ghent University, Geology and Soil Science 2 The Democratic Republic of Congo (DRC) has been an active research area in the field of soil sciences since the 1940s. This has resulted in a comprehensive soil database, completed with climatological and agricultural data in some parts of the country. However, information on hydraulic and physical properties, such as the soil water retention curve (SWRC) and bulk density (BD) of soils, is still missing. Yet, reliable and up-to-date information on SWRC are needed for simulating the soil water balance and estimating crop yields under various management and climate change scenarios. On the other hand, data on BD are required for estimation of carbon stocks and nutrient status of soils in DRC. However, generating hydrophysical data through field and lab measurements is known to be tedious, time-consuming and expensive for large regions. A more affordable solution is the application of pedotransfer functions (PTFs). These are predictive functions which relate more easily available soil data such as texture, organic carbon to more difficult-tomeasure soil properties such as SWRC and BD. Yet, most effort has been dedicated to develop PTFs valid for soils in temperate-climate regions and only few PTFs have been developed for soils in tropical-climate regions such as DRC. A preliminary study has shown the need of developing reliable PTFs for estimating hydrophysical properties of soils in DRC. Therefore, PTFs have been developed to predict water retention and BD for highly weathered soils in the South-Western part of DRC called Lower Congo. Data generated by Lower Congo PTFs have then been used to construct a preliminary map of hydraulic information for soils of Lower Congo. This map, combined with the Soil and Terrain database for DRC, will help to define guidelines for the optimization of agricultural production and environmental protection for sustainable land management at various spatial and time scales. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Ammonia and nitrous oxide emission factors of land applied cattle manure in Alberta and Ontario Model development and testing of soil temperature in DNDC for the effects of snow, biomass and residue cover and soil texture Lilong Chai1, Roland Kröbel1, Douglas MacDonald2, Shabtai Bittman3, Henry Janzen1, Karen Beauchemin1, Sean McGinn1, Shannan Little1, Myra Martel1* Baishali Dutta1, Brian Grant1, Katelyn Congreves1, Ward Smith1, Claudia WagnerRiddle2, Andrew VanderZaag1, Raymond Desjardins1 1 Lethbridge Research Centre, AAFC Environment Canada, Science & Risk Assessment 3 Pacific Agri-Food Research Centre, AAFC 2 Ammonia (NH3) and nitrous oxide (N2O) emissions from land applied animal manure devalue the beneficial contribution of manure nutrients and lead to environmental problems such as poor air quality, acidification and eutrophication of water/soil, and climate change. Assessing NH3 and N2O emission factors [(kg (N emitted) (kg manure-N)-1)] for land application of beef and dairy cattle manure is necessary for quantifying gaseous nitrogen (N) emissions at a regional or national level from animal agriculture and to develop mitigation strategies for soil nutrients management. In this study, both annual and monthly NH3 and N2O emission factors of land applied beef and dairy cattle manure were assessed for the provinces of Alberta and Ontario, Canada. Changes in manure application methods (i.e., broadcasting solid manure on tilled and no-till land, broadcasting liquid manure, banding liquid manure with drop hoses, and deep and shallow injection) and application time of the year (month) in different ecoregions were incorporated to develop provincial-ecoregion emission factors. Indirect N2O emissions from NH3 re-deposition and nitrate lost by leaching and runoff were quantified for different cattle categories. The emission factors of NH3 and N2O derived in this study differ from default values recommended by IPCC (2006). For example, the IPCC (2006) recommends 0.2 kg (NH3-N) (kg manure-N)-1 as the NH3 emission factor of land applied animal manure. In our study, computed emission factors are ranging from 0.01 to 0.5 kg (NH3-N) (kg manure-N)-1 for applied cattle manure based on local climate conditions, manure application methods and times, and tillage factors, etc., in Alberta and Ontario. 99 | P a g e 1 2 Agriculture and Agri-Food Canada University of Guelph Agro-ecosystem models, such as the DNDC (Denitrification and DeComposition) model are useful tools when assessing the sustainability of agricultural management. Predictions of soil temperature estimations are important as it regulates many soil biogeochemical processes that lead to greenhouse gas emissions (GHG). The objective of this study was to improve the surface soil temperature mechanism in DNDC to account for the effects of snow cover, soil texture and crop management in northern latitudes. Thermal conductivity and heat capacity of the soil were used to estimate soil temperatures and influenced by the soil texture in frozen and unfrozen conditions along with effects of canopy and snow cover. Two years of daily soil temperatures (5 cm depth) from two sites with sandy loam and clay soils (Alfred, ON) were used for calibration of the model mechanism. Statistical evaluations of the calibration data demonstrated that the model had high correlation coefficients of R2 > 0.90, high model efficiencies (EF > 0.90) and low root mean square errors of 2.89 (°C) for sandy loam soil and 2.92 (°C) for clay soil respectively. The calibrated model was validated using observed soil temperatures across four field plots (Guelph, ON) with conventional and best management practices (no till, cover crop). The validation results indicated trends of high model accuracy (R2 > 0.90, EF ≥ 0.90, RMSE < 3.00°C) in capturing the effects of management on soil temperature. These developments in soil heat transfer mechanism will allow DNDC to better characterize biogeochemical processes that lead to GHG emissions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil pH is a good predictor of dominating N2O production pathways under aerobic conditions Comparison of nitrous oxide emissions from a gray soil subject to different long-term fertilizer and manure applications at the University of Alberta Breton Plots Yi Cheng State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science Mekonnen Giweta, Miles Dyck, S.S. Malhi, Sylvie Quideau, Dick Puurveen University of Alberta, Renewable Resources It is commonly believed that nitrification is the dominant process for N2O production under aerobic conditions. However, this has been challenged by recent studies on acidic soils, where denitrification has been found to dominate N2O production. Analyzing the data collected from peer-reviewed literature, we found that pH was a critical factor regulating N2O production pathways under aerobic conditions. There is a pH threshold of approximately 4.4, below which denitrification dominated N2O production, and vice versa. A decrease in soil pH can significantly increase the contribution of denitrification to N2O production. Overall, this minireview increases our understanding of N2O sources in soils under aerobic conditions. 100 | P a g e Long-term soil experiments have shown that soil nutrient cycling processes are sensitive to long-term management practices such as rotation, tillage and fertilizer applications and that long-term balanced fertilization can increase fertilizer use efficiency over the long-term. A specific example of changes in soil nutrient pools and supply as a result of change in management is in North Dakota where N recommendations published in the North Dakota State University fertilizer guide were reduced by 40 – 50 lbs N/ac if the soil has been under no-till management for more than 6 years. The short-term yield and nutrient uptake response to added N and S fertilizers is well documented, but there is a lack of information on the N2O emissions in S-deficient soils with respect to shortand long-term N and S fertilization and rotation. Further, the N and S fertility research on annual crops has primarily consisted of short term, 3 to 5 year experiments which do not allow the long-term influence of rotations and fertilization regimes on yields, uptake and GHG emissions to be quantified. We hypothesize that different long-term fertilizer and manure applications have a significant influence on growing season nitrous oxide emissions. To test this hypothesis, we have measured soil N2O emissions in the field and in laboratory incubations from various long-term fertility treatments at the University of Alberta Breton Classical Plots. Specifically, we focus on how long-term application of N and S fertilizers may influence N2O emissions and production processes. The Breton Classical Plots were established in 1930 and are the longest running long-term agricultural soil experiments on S-deficient, grey and dark grey wooded soils in North America. Preliminary results show that contemporary soil nitrous oxide emissions are sensitive to long-term fertilizer management (i.e., manure versus inorganic fertilizers; and/or different combinations of macronutrient fertilizers). Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil Nitrous Oxide Emissions from Cropland in Southern Manitoba Nitrifier and denitrifier abundances in vineyard soil in response to agricultural management practices Amal Roy1, Aaron Glen2, Alan Moulin1, Henry Wilson2 1 2 Brandon Research Centre, AAFC Science and Technology Branch, AAFC Tanja Voegel1. Mesfin Fentabil2, Craig Nichol2, Louise Nelson1 1 University of British Columbia, Biology University of British Columbia, Earth and Environmental Sciences 2 Globally, the agricultural sector is the largest anthropogenic source of nitrous oxide (N2O) to the atmosphere, the majority of which can be attributed to biogeochemical transformations of nitrogen (N) added to cropland soils. The Canadian Tier II methodology used for national GHG inventory reporting implicates the application of synthetic N fertilizer to cropland soils as the largest anthropogenic source of N2O nationally and indicates that emissions from this source have increased by more than 70% between 1990 and 2012. As synthetic N fertilizer application is the main source of anthropogenic N2O globally and nationally, efforts to manage soil fertility more efficiently have a significant potential to reduce overall emissions from agriculture. The objectives of this study are to identify the relative influence of soil type, management and climate on soil N2O emissions and to measure the emission per unit yield for a range of cropping systems in the region. In ongoing studies beginning in 2012, soil N2O fluxes have been measured using the static-chamber technique in various agroecosystems in southern Manitoba. The farm characteristics vary from integrated crop-livestock operations with beef cattle manure and compost applied to soil as nutrient amendments, to a mature no-till cropland with variable rate N fertilizer management. Surface soil textures are similar at the majority of the sites but the organic C content and inorganic N availability of surface soils vary considerably. Soil temperature and moisture content were monitored during the measurement periods and related to the timing and magnitude of N2O emissions. These measurements of soil N2O emissions from cropland in the subhumid eastern Canadian Prairies may help to refine and revise estimates for regional inventories, particularly with regards to coefficients related to hydrology, soil texture, climate, and soil management activities. Current results from the research will be shared and discussed. 101 | P a g e Nitrification and denitrification are the main microbial processes responsible for the loss of applied fertilizer nitrogen from agricultural fields. In addition, both metabolic pathways can produce nitrous oxide, a potent greenhouse gas. Soils of a Merlot vineyard in the semi-arid inter-mountain basin environment of the Okanagan Valley in British Columbia, Canada were analyzed for changes in the abundances of genes coding for enzymes associated with nitrification and denitrification in response to different agricultural management practices in 2013. Management practices applied included irrigation via micro-sprinkler or dripper, fertilization with urea or compost, and bark mulch applications. DNA was isolated from soil samples collected during spring thaw (February), at the beginning of irrigation (May), during the fertigation period (June) and at the end of the irrigation and growth season (September). The DNA was quantified by quantitative real time PCR using primers for the genes: 16S rRNA (a measure of total bacteria), amoA (coding for ammonia monooxygenase, the first step in the nitrification pathway,) nirS (coding for nitrite reductase in the denitrification pathway) and nosZ (coding for nitrous oxide reductase, the final step in the denitrification pathway). Abundance of total bacteria was higher in mulch treatments, and mulch also lowered soil pH and increased organic matter, C/N ratio and water-filled pore space (WFPS). Abundance of amoA genes was higher with urea treatments. Compost treatments resulted in higher organic matter, total N, total C, soluble organic C and soil micronutrient contents. NosZ abundance was higher under microsprinkler irrigation, and this irrigation also increased soil pH. Abundance of nirS genes was positively correlated with organic matter, total N, total C and WFPS. Interestingly, amoA and nosZ gene abundances were correlated positively and negatively, respectively, with nitrous oxide emissions. Management practices influencing the abundance of these genes could aid in mitigation of nitrous oxide emissions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Metaproteomics of soil and leaf litter – Potentials and Challenges Soil carbon stocks and tillage intensity in organic farming systems: a meta-analysis Katharina Keiblinger1, Thomas Schneider2, Inés Wilhartitz3, Stephan Fuchs4, Kathrin Riedel5, Sophie Zechmeister-Boltenstern1 Caroline Halde1, Julia Cooper2, Marcin Baranski2, Majimcha Nobel de Lange2, Paolo Bàrberi3, Andreas Fliebach4, Joséphine Peigné5, Chistophe David5, Martin Entz6 1 University of Natural Resources and Life Sciences University of Zurich, Plant Biology 3 Swiss Federal Institute of Aquatic Science and Technology, Environmental Microbiology 4 Robert-Koch Institute 5 University Greifswald, Microbiology 2 Environmental metaproteomics is a quickly developing field. Potential applications of environmental metaproteomics provide new possibilities for the analysis of microbial communities and their activities in terrestrial ecosystems. Protein identification in environmental samples together with the determination of their phylogenetic origin and their ecological function is expected to provide advanced knowledge into the role of the microbial component of biogeochemical processes. Terrestrial ecosystem research dealing with SOM turnover differentiates between the litter layer and mineral soil. While deciduous litter is characterized by thin and flat organs while, mineral soil has a more complex structure comprising micro- and macroaggregates formed by charged humic substances and clay minerals. Hence, the complexity and heterogeneity of soil samples in contrast to litter samples constitutes a major challenge in protein extraction. Here we present two studies. First we compared efficiencies of soil protein extraction protocols for a beech forest mineral soil. Soil protein extracts were analyzed by two-dimensional liquid chromatography/tandem mass spectrometry (2D-LCMS/MS). Furthermore, we examined the impact of seasonality on the function and composition of a microbial community during leaf litter decomposition. Beech (Fagus sylvatica) leaf litter samples were extracted and separated via 1D-SDS PAGE combined with 1D-LCMS/MS. For the assignment of proteins to phylogenetic and functional groups, the bioinformatic pipeline ‘PROPHANE’ was used for data evaluation. 102 | P a g e 1 Université Laval Newcastle University 3 Scuola Superiore Sant’Anna 4 Research Institute of Organic Agriculture FiBL 5 ISARA Université de Lyon 6 University of Manitoba 2 There has been a lower degree of uptake of reduced tillage in the organic community in Europe compared with the conventional farming community, because of real and perceived challenges associated with increased weed pressure, delayed nutrient mineralization, and the need for deep tillage to incorporate green manures and leys. The overall objective of the study was to identify optimal management practices for successful implementation of reduced tillage in organic farming systems. A metaanalysis approach was used to compare the effects of reduced tillage intensity on soil carbon stocks, weeds, and crop yields. Data on reduced tillage trials in organic farming systems from both published and unpublished sources including raw data from 15 ongoing trials in Europe and Canada were compiled. Compared with deep inversion tillage, all reductions in tillage intensity increased soil carbon stocks by 125 g m-2. No-tillage increased soil carbon stocks relative to shallow inversion by about 222 g m-2. Reducing tillage intensity in organic systems increased weed pressure by 29% and 34%, compared to both deep and shallow inversion tillage, respectively. The impact of reducing tillage on crop yields varied across climates, with a greater reduction in yields in humid continental climates (22%) than in humid oceanic climates (5%). Results showed that significant gains in soil carbon storage can be achieved by adopting shallow inversion tillage rather than deep inversion in organic farming systems, with no significant increase in weed pressure and minimal impacts on crop yields. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Nitrogen release from decomposing legume crop residues over three subsequent crops Hyperspectral Vegetation Indices for Detecting In-Season Nitrogen Stress in a Potato Crop Newton Lupwayi, Yoong Soon 1 2 Athyna Cambouris1, Thomas Morier2, Karem Chokmani2 Lethbridge Research Centre, AAFC Beaverlodge Research Farm, AAFC 1 Crop residue decomposition and N mineralization studies are usually conducted only in one subsequent crop. We determined N mineralization from residues of pea (Pisum sativa L.), faba bean (Vicia faba L.) grown for seed, faba bean green manure (GM) and chickling vetch (Lathyrus sativus L.) GM in three subsequent crops. Pulse crops fixed more N2, particularly faba bean grown for seed (184 kg ha-1) and forage pea (165 kg ha-1) than GM legumes (77 and 95 kg ha-1). Faba bean grown for seed, forage pea and vetch GM residues contained the most N (129-153 kg ha-1), and green pea the least (65 kg ha-1). Green manure residues released more N (> 80% of their contents) than pea residues (about 50% of their N) in the first year when wheat (Triticum aestivum L.) was grown, but pea residues released more N than GM residues in the second and third years when canola (Brassica napus L.) and barley (Hordeum vulgare L.), respectively, were grown. Residues of faba bean grown for seed released 63% of their N in the first year. After three years, only 3-5% GM residue N was unreleased, but pulse crop residues had 13-16% of their N unreleased. Therefore, pulse crop and GM residues had different N mineralization profiles. 103 | P a g e Soils and Crops Research and Development Centre, AAFC Institut National de la Recherche Scientifique Centre Eau Terre Environnement 2 The rate and timing of N applications are important issues in precision agriculture because of the withinfield spatial and temporal variability of soil N availability. The use of remotely sensed spectral data for determining rates and timing of variable rate nitrogen (N) applications at a commercial scale are now available but the most reliable indicators of crop N status must be determined. In-season assessment of potato (Solanum tuberosum L.) crop N status (CNS) is required to better match N fertilizer supply to crop N demand and improve N use efficiency. The objective of this study was to investigate the ability of hyperspectral vegetation indices (HVIs) to assess the CNS and tuber yield of irrigated ‘Russet Burbank’ potato at different growth stages. A 2 yr field experiment was conducted near Quebec City, QC, Canada, on plots receiving five different N rates ranging from 0 to 280 kg N ha -1, with 40% applied at planting and 60% at hilling. Entire plant samples were collected biweekly for determination of the N nutrition index (NNI) as the N status reference method. In-field hyperspectral reflectance derived from a handheld spectroradiometer and using two fields of view (FOV; 7.5° and 25°) was obtained on several dates during both growing seasons. The sensitivity of the five HVIs most correlated to the NNI was evaluated by analyses of variance and least significant differences. It was found that HVIs computed from reflectance in the red-edge spectral region and using a wider FOV were the most appropriate indices to detect potato crop N stress. Among these indices, the CI1rededge (red-edge chlorophyll index 1) was the most sensitive to potato N content and could explain 76% of the variability in total tuber yield at 55 days after planting (DAP). Early detection of N stress in potato crop using the best HVIs could make possible to rectify N deficiency by foliar N applications. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Nitrogen and phosphorus fertilization in wild lowbush blueberry in Quebec Jean Lafond Agriculture and Agri-Food Canada Many studies have shown that wild lowbush blueberry responded very well to fertilization although this crop has relatively low nutrient requirements. The objective of this project was to determine the effect of nitrogen and phosphorus fertilization in wild lowbush blueberry depending on the initial leaf N and P concentrations. The experiment was conducted at 15 blueberry fields located in the Saguenay-Lac-Saint-Jean area in 2012 and 2013. The treatments consisted of four rates of N (0, 30, 60 and 90 kg N ha-1 ammonium sulphate) and three rates of P (0, 10 and 20 kg P2O5 ha-1 triple super phosphate) applied in the spring of the sprout year. SPAD values were significantly correlated with leaf N concentrations. Leaf N, P and K concentrations increased significantly with N fertilization while leaf Ca and Mg concentrations decreased significantly. Phosphorus fertilization increased only leaf P concentrations. Phosphorus fertilization had no effect on fruit yields while N fertilization increased fruit yields on eight sites. 104 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S15: Biochar in Agriculture and Environment/ Le Biochar en Agriculture et en Environnement 105 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Biochar production: a tool to mitigate climate change Patrick Brassard1-2, Stéphane Godbout2, Vijaya Raghavan1, Joahnn Palacios2, Jean-Pierre Larouche2, Dan Zegan2 1 McGill University, Department of Bioresource Engineering Research and development institute for the agrienvironment (IRDA) Biochar amendment alters the molecularlevel composition of soil organic matter in a temperate forest soil Perry Mitchell, André Simpson, Ronald Soong, Myrna Simpson University of Toronto, Chemistry 2 Biochar, a solid porous material obtained from the carbonization of biomass under low or no oxygen conditions (i.e. pyrolysis), has been proposed as a climate change mitigation tool. The pyrolysis of biomass stabilizes carbon in biochar, and when applied to soil, it can be stored for hundreds of years. Moreover, many studies reported that biochar amendment to soil can reduce greenhouse gas (N2O, CH4 and CO2) emissions. Based on a literature review, the chemical composition of biochar was found to have a major impact on soil greenhouse gas (GHG) emissions and on the carbon sequestration potential. Biochars with lower N contents, and consequently higher C/N ratios (> 30), are expected to be more suitable for mitigation of N2O emissions. Moreover, biochars produced at a higher pyrolysis temperature, with O/C ratio <0.2, H/C ratio <0.4 and volatile matter content below 80% may indicate high C sequestration potential. In order to identify the ideal conditions for producing a biochar having the desired characteristics to mitigate climate change, pyrolysis tests will be performed in an auger reactor. Preliminary pyrolysis tests with wood allowed identifying the range of operational parameters suitable for the pyrolysis unit. Final tests with different feedstocks (agricultural residues and energetic crops) will be done, by varying pyrolysis temperature, solid residence time and gas carrier flow rate. Biomasses and pyrolysis products (biochar and bio-oil) will be characterised in order to perform a mass balance on different elements. These results will allow demonstrating the relation between feedstock, pyrolysis operational parameters and biochar characteristics. 106 | P a g e Biochar is added to soil to mitigate climate change and enhance soil fertility but may stimulate microbial activity and increase native soil organic matter (SOM) mineralization, possibly leading to changes in SOM composition. To investigate this, we incubated wood biochar in a temperate forest soil for 32 weeks at three concentrations (5, 10 and 20 t/ha). SOM biomarker extractions and nuclear magnetic resonance (NMR) spectroscopy were applied to characterize the SOM composition at several time intervals. At 10 and 20 t/ha biochar application rates, the concentration of phospholipid fatty acids (PLFAs) specific to Grampositive and Gram-negative bacteria as well as actinomycetes increased after an adaptation period of 16 weeks. Solvent extraction showed increases in the concentration of sugars and short-chain n-alkanols and n-alkanoic acids during this interval, suggesting microbial adaptation to biochar-amended conditions. Increases in the ratio of bacteria/fungi and lower ratios of Gram-negative/Gram-positive bacteria suggest a microbial community shift in favour of Gram-positive bacteria. CuO oxidation revealed progressive oxidation of syringyl and vanillyl phenols with higher biochar application rates over time. Solution-state 1H NMR analysis of base-extractable SOM showed decreases in the proportions of labile O-alkyl components and an increase in more recalcitrant polymethylene-type carbon in biochar-amended samples. The results suggest that biochar-mediated shifts in SOM composition and labile carbon degradation may reduce soil fertility in biochar-amended systems. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Charcoal amendment changes soil carbon dynamics through its impact on (micro-) biological functioning after several centuries Does a Meat and Bonemeal Biochar Enhance Petroleum Hydrocarbon Degradation in Frozen Soil? Christophe Naisse1, Thi Phuong Ngo1,2, Bernard Davasse3, Abad Chabbi1, Cornelia Rumpel1 Erin Karppinen1, Katherine Stewart2, Steven Siciliano1 1 IEES Paris, (UMR 7618, CNRS, UPMC, IRD, INRA), Centre AgroParisTech 2 Universidad de la Frontera, BIOREN-UFRO 3 CNRS, CEPAGE (ADESS, UMR 5185), Ecole nationale supérieure d'architecture et de paysage Biochar is a charcoal from biomass pyrolysis, used as soil amendment and most likely stable for several centuries. However, the long-term evolution of physicochemical and biological functioning of biochar amended soils is poorly understood, which renders the evaluation of this strategy as climate change mitigation uncertain. We investigated (i) the stability of organic carbon in a soil horizon amended with charcoal four centuries ago in comparison with adjacent unamended soil, and (ii) carbon dynamics following a new input of labelled 13C charcoal and plant residue. Here we show that long-term charcoal amendment led to more rapid decomposition of the new materials by about 17%, but induced lower soil organic carbon mineralization by about 30%, i.e. a negative priming effect, while improving durably the soil physicochemical properties. These changes probably promoted higher microbial activity and thus new substrate mineralization, while specific adaptation of microorganism to charcoal degradation was not observed. The negative priming effect induced by a second charcoal amendment can be due to a physical protection of a soluble carbon fraction at the surfaces of labelled charcoal. In contrast, the negative priming effect induced by plant residue input may be more likely due to a shift of substrate utilization by microbial communities evolving in a nutrient-rich environment. Our results demonstrate that biochar amendment modifies the carbon dynamic of soils in the long-term. We propose that studies evaluating environmental and economic impacts of the expansion of biochar strategy should incorporate the long-term modification of biogeochemical cycles. 107 | P a g e 1 2 University of Saskatchewan Yukon College Landfarming is a common bioremediation method in cold regions but is a slow and costly process that is limited by extreme environmental conditions. Conventional methods of petroleum hydrocarbon (PHC) remediation in landfarms rely on fertilizer additions and soil turning to stimulate the microbial community to catabolize organic contaminants; this approach, however, has yielded inconsistent results in cold environments. Current bioremediation strategies are targeted toward the short summer months; but this is often an insufficient amount of time to meet soil remediation targets and environmental criteria. Substantial bioremediation can occur in frozen soil so extending microbial degradation of PHC further into the winter months could increase turnover rates of landfarmed soil. Biochar is a soil amendment that results from the heating of organic biomass under oxygen limited conditions, and has been used in remediation to sorb organic pollutants and stimulate microbial degradation. There are advantages and disadvantages to the use of all feed stocks; however, utilization of a local source of the feed stock is ideal as it can stimulate the economy while recycling waste materials. The aim of this study was to determine if meat bonemeal (MBM) biochar additions could enhance PHC degradation in landfarmed soil from Iqaluit, and to link this degradation to measureable chemical and microbial responses. Over 90 days, 3% (w/w) MBM biochar significantly reduced the F3 (equivalent nC16-C34) PHC in frozen soil by 22%, as compared to the fertilizer control. In these frozen soils, MBM biochar increased liquid water (liquid) but did not increase nutrient supply rates. The MBM biochar increased total viable PHC-degrading populations in frozen soils compared to controls. Furthermore, in frozen soils, genes that encode for aromatic but not alkane hydrocarbon degradation, increased in all treatments. We speculate the biochar is providing a unique eutectic habitat well suited to degrading aromatic hydrocarbons. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 1 2 Use of Biochar as a Soil Amendment for Fertility Improvement in the Sandy Soils of Labrador Soil CO2 and N2O emissions: Is the mitigation efficiency of biochars impacted by periodic applications of mineral nitrogen fertilizer? Kayla Stewart1, Joinal Abedin2, Peter Beckett1, Graeme Spiers1, Keith Chaulk2 Vicky Levesque1, Philippe Rochette2, Noura Ziadi2, Martin Chantigny2, Martine Dorais1, 3, Hani Antoun1 Laurentian University, Biology Labrador Institute of Memorial University There is a need to improve local agricultural practices for long term, sustainable and affordable food security for food production in remote and northern communities. With a short growing season, the low organic matter and coarse textured acid soils are not conducive to modern agricultural practices without the introduction of materials to build soil fertility levels and enhance moisture holding capacity. The addition of biochar, a carbonaceous material produced by pyrolysis, with added nutrients can potentially improve water holding capacity, cation exchange capacity (CEC), soil organic matter, soil structure, and reduce soil acidity. In 2014, field studies conducted in Happy Valley Goose Bay, Labrador demonstrated that the addition of biochar or fishmeal or commercial fertilizer alone had little impact on crop yield. However, plots with applications of biochar with either fertilizer or fishmeal successfully improved beet yield. Single or multiyear applications of biochar of 20-40 t/ha with approximately 300 kg/ha of 20-14-15 specialty fertilizer blend produced excellent beet yields of up to 50 t/ha wet weight. These studies will guide the implementation of improved soil management practices to enhance soil fertility and moisture retention in the sandy soils in remote communities. 108 | P a g e 1 Soils and Agri-Food Engineering & Horticultural Research, Laval University 2 Soils and Crops Research and Development Center, AAFC 3 Horticultural Research and Development Centre, AAFC Little is known about the impact of biochars for mitigating soil CO2 and N2O emissions after periodic applications of mineral nitrogen fertilizer. We hypothesized that the mitigation efficiency of biochars would (i) decrease with time following successive N applications, and (ii) be influenced by soil C availability. Since feedstock nature and pyrolysis temperature influence biochar physicochemical properties, four biochars (maple bark 400°C, 550°C and 700°C and pine chips 700°C) were mixed into a clay soil at 5% (w/w) with or without compost at 3.75% (w/w). Experimental units were incubated for 244 days at 21°C and 80% relative humidity, and mineral nitrogen fertilizer was added (35 ug N g-1 soil) to all treatments at the beginning of the experiment and every three months. All biochar types resulted in lower total cumulative CO2 (13 to 52%) and N2O (24 to 95%) emissions compared to the unamended control (0% biochar). These reductions were lower with than without compost for N2O (50 vs 84%) but not for CO2 (32 vs 34%), possibly because of immobilization of mineral N in presence of compost. This is supported by the increased CO2 but reduced N2O emissions following the addition of the C-rich compost. Reductions in CO2 emissions differed among biochars, indicating a significant effect of material properties on C dynamics. The impact of incubation time on biocharinduced changes in gas emissions differed between CO2 and N2O. Whereas the impact of biochar on N2O emissions remained constant during the incubation (67%), their CO2 mitigation efficiency was three times greater after 244 days (50%) than early after biochar addition (15%). We conclude that the CO2 and N2O mitigation efficiency of the selected biochars was not decreased following successive N additions and that their capacity for reducing soil N2O emissions was lower in presence of C-rich compost. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Mineral based nutrient dynamics of dual feedstock biochars under increasing pyrolysis temperatures Mechanisms of soil pH regulation by biochar amendments and consequences for biochar long-term effects Benjamin Pace, Sarasadat Taherymoosavi, Paul Munroe, Stephen Joseph Frédéric Rees Université de Lorraine – INRA Soils and Environment University of New South Wales, Materials Science and Engineering Limited research exists on nutrient/mineral transformation kinetics during biochar production, particularly at the nanoscale, and the effect of pyrolysis temperature on this process. An understanding of this would facilitate more accurate predictions of char-soilmicrobe interactions for given feedstock types and pyrolysis temperatures, and thus improve production regimes. This study is investigating the possible pathways of mineral transformation in three biochars composed of two feedstock. A suite of analyses were employed to determine bulk and surface, amorphous and mineral composition of chars prepared at 105,450,550 and 650°C with ingredients: *(50% each by mass for samples 1 and 2. 1) Wheat-Straw and Basalt [WSBS], 2) Wheat-Straw and Chicken Litter [WSCL], 3) Municipal Solid Waste [MSW]. Sample analysis identified diverse amorphous and mineral phases forming, with significant variation in inorganic content between 450-650oC. Bulk proximate/ultimate and elemental (XRF) analyses suggested phase composition transitions peaking at 550oC in WSCL (Al, Si and Fe content peak), despite a low initial mineral content, while the inverse was true for Ca, Mg, Na, K, S and P. Surface and sectional EDS/microscopy revealed significant surface silicon deposits, also surrounding mineral agglomerations and pore boundaries in section. Often adjacent Iron-phosphate and carbonates were also identified. EDS on a MSW105 TEM specimen showed co-location of iron, aluminium, silicon and oxygen in sub-micron particles, suggesting intimate bonding between iron and clay-like complexes. Phosphorus formed an interface between this complex and oxidised Ca/C complexes, likely calcium carbonate. WSBS analysis also suggested iron/calcium/magnesium oxides present in sub-micron agglomerations adjacent bentonite-like complexes. Intimately bound mineral phases were observed in nanoporous char phases. Ongoing spectroscopic analysis to date confirmed silicon bonding, and suggested possible Si-C phases. XRD detected carbonate, sulfate, nitrate (MSW only), and phosphate ions, bonded interchangeably with calcium and sodium anions. These results suggest plant derived silicon release may be governed by pyrolysis temperature, and along with carbonates and phosphates may play a significant role in retaining labile organics in various nutrient available mineral forms. 109 | P a g e Soil amendments of biochar, i.e. the solid product of biomass pyrolysis, have been increasingly investigated over the last few years as a way to store stable C in soils, to improve crop production and to remediate degraded and contaminated land. Many short-term effects of biochar on soil chemical and biological properties may be explained by the observed increase of soil pH, largely reported in the recent scientific literature for acid or neutral soils. However, both the mechanisms by which biochar is affecting soil pH and the duration of pH changes remain unclear. Using batch reactors and column leaching experiments, we examined the response of a wood-derived biochar pyrolyzed at 450°C to the addition of various quantities of HNO3 or NaOH. Our results enable to identify both the dissolution of biochar’s mineral phases, e.g. calcite and Si/Al oxides, and cation exchange at the surface of biochar as the two major mechanisms explaining biochar’s buffering capacity. The importance of these mechanisms vary in dependence with time and pH evolution. Observation of old charcoal amendments at various sites suggest however that, depending on initial soil pH and soil buffering capacity, the effects of biochar caused by the modification of soil pH may not last more than a few years. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Biochar as a component of potting soils: case studies Impact of rice husk biochar on selected soil properties of two Alfisols of Sri Lanka Sébastien Lange, Suzanne Allaire Duminda Vidana Gamage1, Ranjith Mapa2, Saman Dharmakeerthi2, Asim Biswas1 Université Laval, Centre de Recherche sur les Matériaux Renouvelables (CRMR) 1 2 Tons of residual organic materials (ROM) are produced yearly in Quebec, but only 20% of these ROM are recycled. The most important producers are forest, agricultural and urban industries. In addition, the Quebec government voted a law prohibiting ROM disposition in landfills as soon as 2020. Pyrolysis of these ROM into biochar and other products (gases and bio-oil) opens promising markets for these ROM. Horticulture is such a market. The reintroduction of these ROM into production cycles would improve ecological footprint and decrease importation of different materials by this industry. Biochar is already used in several countries as a component of potting soils. Peat, perlite, and vermiculite are considered as none renewable and expansive products in addition to their negative carbon budget. Moreover, perlite and vermiculite must be imported in Quebec. Comparatively, biochar is local, highly renewable, has a positive carbon budget and its price may considerably reduce once the law, concerning ROM, is reinforced. The potential of local biochars as a component of potting soils for forest, ornamental and horticultural productions have rarely been tested under Quebec conditions. This presentation will discuss cases where biochars were used for ornamental and forest production in different proportions as substitute of perlite and/or peat in potting soils. The influence of biochar on plant growth and quality will be discussed along with economical aspect of biochar usage in these contexts. 110 | P a g e McGill University, Natural Resource Sciences University of Peradeniya, Soil Science Despite large number of studies on biochar and soil properties, few studies have investigated the effects of biochar on contrasting soils over time. This study investigated effects of four rice husk biochar rates (0, 0.1, 0.5 and 1%) in two Alfisols (Sandy and Sandy loam) of Sri Lanka. Soil pH, cation exchange capacity (CEC), soil organic carbon (SOC), bulk density, water retention, saturated hydraulic conductivity (Ks) and mean weight diameter (MWD) were determined at the beginning (D0) and end (D180) of the incubation period. Significant changes in soil properties including increases in pH, CEC, SOC, water retention at field capacity, Ks and reduction in bulk density were observed at higher rates of biochar (0.5 and 1%). Despite the increase in MWD at D180 in two soils, Sandy loam soil showed a pronounced increase over time. Sandy soil showed the highest improvement in CEC over Sandy loam at D180. Biochar showed a potential for ameliorating acidity especially in slightly acidic Sandy soil. Result of this study suggested that the changes in soil properties such as pH, water retention and SOC over time are little in two soils, while CEC and MWD respond differently in two soils over time. This study indicated the importance of soil type and time in determining the value of rice husk biochar as a soil amendment However, long-term field studies are necessary to confirm and quantify the long-term benefits of rice husk biochar under different cropping systems. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Adsorption of copper by pine sawdust biochar in synthetic oil sands processaffected water Kangyi Lou1, Anushka Upamali Rajapaksha2, Yong Sik Ok2, Scott Chang1 1 Department of Renewable Resources, University of Alberta, Edmonton, AB T6G 2E3, Canada 2 Korea Biochar Research Center, Kangwon National University, Chuncheon 200-701, Korea Copper (Cu (II)) is the most abundant metal in the oil sands process-affected water (OSPW). Its concentration exceeds the provincial and federal guidelines and is toxic to aquatic life. In this study, pine sawdust biochars produced at 300 and 550 °C with and without steam activation were characterized and evaluated for adsorption of Cu (II) in synthetic OSPW. Pine sawdust biochars were determined by their surface structures and chemical properties (e.g. functional groups, elemental composition, and point of zero charge). Isotherm and kinetic studies were conducted to investigate the adsorption capacities and mechanisms. The results demonstrated that biochar surface characteristics varied with the pyrolysis condition. Langmuir and pseudo-second order models were the best-fit for isotherm and kinetic studies, respectively. According to the Langmuir parameters, the maximum adsorption capacities of the biochars made at 550 °C were around 2.5 mg g-1, which were twenty-fold higher than those made at 300 °C. However, steam activation did not cause any significant difference in the biochars’ adsorption performance. The kinetic study suggested that chemisorption or chemisorption involved valence forces was the limiting factor of the sorption, and precipitation and cation-π interaction were likely the primary mechanisms involved in the process. This study implied that pine sawdust biochar produced at 550 °C have a great potential to remediate Cu (II) pollution in the OSPW. 111 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S16: Management Zones in Precision Agriculture/ Zones d’Aménagement en Agriculture de Précision 112 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 High-resolution elevation data (h-red) clouds generated on-farm facilitate detailed soil mapping and precision management of Ontario farm fields Doug Aspinall, Stewart Sweeney Ontario Ministry of Agriculture, Food and Rural Affairs Response of corn to N rates as a function of soil properties in a precision farming context Nicolas Tremblay1, Carl Bélec1, Philippe Vigneault1, Lucie Grenon1, Edith Fallon1, Yacine Bouroubi2 1 2 Publicly-available digital elevation data cloud sources for Ontario’s agricultural landscapes have evolved over the past two decades. However, they have generally lacked both the spatial resolution and accuracies required for detailed soil mapping and precision cropping system management at the farm field level. Over this same time period, some Ontario farmers have acquired or outfitted their cropping system equipment with high-resolution global positioning system (GPS) guidance technology. Soil landscape feature detail was assessed for digital elevation models (DEM’s) derived from high-resolution elevation data (HRED) clouds captured with these on-farm-deployed RTK (real-time kinematic) GPS units for a series of farm fields from different soil landscapes across the province. Independent H-RED were captured with either airborne light detection and ranging (LiDAR) or ground-based laser scanner technologies. 5 m X 5 m DEM’s were crafted from these H-RED results to represent the “ground-truth” situation for each field. Onfarm-generated H-RED clouds, for these fields, were captured with GPS units from different manufacturers mounted on cropping system equipment from different manufacturers. Root Mean Square Error (RMSE) analyses were performed to the compare the on-farmgenerated 5 m X 5 m DEM results with the corresponding “ground truth” 5 m X 5 m DEM results. The on-farm-generated H-RED DEM quality provided soil landscape feature delineation required for detailed digital soil map production. Ontario farmers’ investments in H-RED RTK-GPS technology for their cropping system equipment facilitate decision-making for soil-based precision management. 113 | P a g e Agriculture and Agri-Food Canada Effigis Géosolutions Adjustments to bring to N rates recommendations as a function of soil properties are still difficult to define. Seven commercial corn fields were treated with inseason N fertilization rates in a strip pattern over the years 2012 to 2014. The sites were characterized from a pedological standpoint and mapped for shallow and deep apparent electrical conductivity. The experimental treatment lay-out was made so that the N fertilization rates crossed all variations in soil properties. The fields were harvested with combines equipped with GPS and yield monitors. It was therefore possible to compare the yields obtained with the N rates provided in interaction with the soil properties. Soil apparent electrical conductivity thresholds were established for each field to determine if zones could be managed for differential N fertilization. Nitrogen rates maximizing corn production differed for comparable soil properties at different sites. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Multi-temporal, multi-parameter geospatial data sets facilitate detailed soil mapping of Ontario farm fields Sustainable cropping system management zones: a central role for intrinsic soil properties, landscape feature delineation Doug Aspinall, Stewart Sweeney Doug Aspinall, Stewart Sweeney Ontario Ministry of Agriculture, Food and Rural Affairs Ontario Ministry of Agriculture, Food and Rural Affairs Cropping system equipment, outfitted with global position system (GPS) technology, captures highresolution elevation data (H-RED) clouds with each pass on Ontario’s farm fields. Soil landscape feature delineation in sentinel fields, where multiple H-RED sets have been obtained, was conducted (Bangs et al. 2013; Sweeney and Aspinall, 2014). Independent HRED capture technology (LiDAR and ground-based laser-scanning) results verified that these on-farmgenerated H-RED clouds can be used to craft 5 m X 5 m digital elevation models (DEM’s) of the quality required to make detailed soil maps at the within-field scale of precision crop management decision-making. Annual, geospatially-referenced crop yield data (CYD) sets were collected with GPS-enabled harvest equipment for these same fields. Each of these annual CYD sets was post-processed with the methodology described by Aspinall (2013; 2014) to create a time series of annual crop yield maps. Aggregation of these multi-temporal CYD results, into crop yield index (CYI) maps for each field, provides crop performance trend information directly attributable to intrinsic soil properties and soil landscape features (Aspinall and Sweeney, 2015). Multi-temporal remotely-sensed (RS), high-resolution imagery from both in-crop and post-crop seasons for these fields, was analyzed to differentiate soil landscape patterns within these fields. The crop performance (via CYI maps), RS within-field soil landscape patterns and H-RED DEM landform disaggregation results were combined with strategic soil site investigation results. Precision agricultural technique adaptation to field crop production systems in Ontario has evolved since the 1990’s. Long-term crop yield monitoring datasets have been accrued by early-adopting farm managers. Senior Soil Scientists of the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) have conducted high-resolution soil surveys of sentinel farm fields with these rich geospatially-referenced crop performance information histories. The combination of detailed soil property and landscape feature knowledge with multi-temporal crop performance results for each crop in these rotations was used to delineate management zone domains within fields. All fields described in this study were managed without irrigation supplementation. Intrinsic soil moisture retention conditions throughout the fields, both within the soil profile (texturally-driven) and within local basin structures (form-driven), are major soil property and landscape feature contributors to the segmentation of these fields into management zones. A strong positive correlation trend was repeated year-after-year between crop performance and field areas that capture and retain soil moisture through the critical water deficit periods of the growing season. Sustainable cropping system management zones have aligned well with these intrinsic soil properties and local basin soil landscape feature locations within the fields that were examined in this long-term study. 114 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The Spring Nitrate-N Soil Test can improve the General N Recommendation for Corn Production on a Clay Loam in Southwestern Ontario Xueming Yang, Craig Drury. Jingyi Yang, Dan Reynolds, Mary-Anne Reeb Greenhouse & Processing Crops Research Centre, AAFC Supplying enough nitrogen (N) and increasing fertilizer N use efficiency for corn (Zea mays L.) are essential goals for optimizing corn production and for minimizing N loss to the environment. Two field studies (5 consecutive years) with five N application rates (0, 50, 100, 150, 200 kg N ha-1) were conducted on a Brookston clay loam (Orthic humic Gleysol) in southwestern Ontario to evaluate the two N fertilizer recommendation methods (spring nitrate-N test or the Ontario corn N calculator) for their ability to predict the optimal N application rate for corn in a winter wheat (Triticum aestivum L.) – soybean (Glycine max) – corn rotation. We found that if the spring soil nitrate-N test was used in conjunction with the Ontario corn N calculator, the estimate of the optimal N application rate could be improved. Further, high rainfall during the February to April period was associated with lower spring soil nitrate levels and the target corn yield should be increased 12.0 Mg ha-1 instead of the 10.0 Mg ha-1 that is currently being used for this soil type and high-heat unit area. 115 | P a g e Managing soil interfaces with 4R crop nutrition Tom Bruulsema1, Kevin King2, Merrin Macrae3 1 International Plant Nutrition Institute USDA Agricultural Research Service 3 University of Waterloo 2 Trends over the past twenty years in the Western Lake Erie Basin show increasing algal blooms and loadings of dissolved phosphorus. Multiple causes have been postulated. Among them, the source, rate, timing and placement of phosphorus applied to cropland represent management choices that impact losses at the edge of the field. Reviewing published and more recent unpublished results of measured loadings and concentrations of phosphorus in runoff and tile drainage, evidence supports the relevance of all four aspects of phosphorus application management. These practices, however, interact with tillage and crop rotational choices to influence losses of particulate forms of phosphorus as well as those of other nutrients including nitrogen. Vertical stratification, soil macropores, and drainage factors need to be considered. In particular, producers need better advice to ensure that tillage practices and nutrient application practices complement one another to simultaneously minimize losses of soil sediment, and particulate and dissolved forms of phosphorus, all of which originate from the soil surface. The integrated approach known as 4R Nutrient Stewardship has been recognized as part of the solution to the issue. The concept has begun to influence behaviour as indicated by participation in voluntary programs, and incorporation into mandatory educational requirements for on-farm fertilizer application. Experiences in the Lake Erie Watershed provide learnings relevant to global management of nutrient losses from agricultural soils. By addressing economic, environmental and social dimensions of sustainability, 4R Nutrient Stewardship solutions seek to support the productivity increases required to address growing global demand while improving water quality. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 1 2 Irrigation strategies for strawberry in California and Quebec: yield, water savings and return on investment Development of a real-time method for assessing subsurface drainage systems performance in cranberry production Jean Caron1, Guillaume Létourneau1, Lélia Anderson1, Valérie Bernier-English1, Carole Boily1, Julien Cormier1, Nicolas Watters1, Oleg Daugovesh2, Laurence Gendron1 Diane Bulot, Awa Mbodj, Jean Caron, Silvio Gumiere Université Laval, Sols et de Génie Alimentaire University of California, Cooperative Extension Worldwide, water is a precious resource that is becoming increasingly scarce as the population grows and water resources are depleted in some locations. It obviously affects strawberry production and many strawberry growers have taken steps to improve water use efficiency through different means, including the use of wireless tensiometer systems and more widely, estimates of Crop Evapotranspiration from weather stations. However, irrigation setpoints recommended for tensiometer use in strawberry are suspected to vary according to soil type, growing environment and plant growth stage. Studies were conducted in 5 different locations and over four years, testing different irrigation strategies. Soil texture varied from clay to sandy loam. The most appropriate set points for initiating irrigation was found to be around -10 kPa in all mineral soils. Improved productivity was observed with most tensiometer-based scenarios relative to irrigation management based on crop evapotranspiration estimates. Threshold varied little with growth stage. Tension based irrigation management resulted in 11% water savings and 12% yield increase on average and return on investment period was about 2 months in most scenarios tested. 116 | P a g e Université Laval, Pavillon de l’Envirotron Efficient drainage systems are essential in the development of more intelligent precision irrigation methods in cranberry production. Most cranberry fields are equipped with subsurface drainage systems used for water table control and excess water removal. In fact, cranberry reveals high sensitivity to wet conditions with an important decrease of crop yields caused almost exclusively by dysfunctional drainage systems. Previous works have highlighted the need to improve existing drainage systems. The main objective of this study is to present a new real-time method for assessment of subsurface drainage system performance and to provide strategies to improve their efficiency. During the 2013 and 2014 crop seasons, real-time experimental devices (observation wells, tensiometers, and pressure sensors) were installed in 22 fields (14 in Manseau and 8 in the Lac-St-Jean area, Québec, Canada) in order to monitor the water table and soil matric potential. These devices obtained from our partner Hortau Inc. allow for an estimation of soil drainage efficiency following precipitations and/or irrigations. In order to assess the relationship between drainage efficiency and soil properties, 960 undisturbed soil cores were collected over 8 fields and brought back to the laboratory for hydrodynamic soil properties characterization. Principal component analysis and cluster analysis were performed on data obtained from hydraulic conductivity, desorption curve, bulk density, soil porosity, granulometry, and yields. Throughout the winters of 2014 and 2015, a ground penetrating radar was used to survey the first few meters of soil in order to characterize the soil profile. This mapping of the soil will then be combined with soil properties, completing the diagnostic method. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Controlling water table depth for a sustainable cranberry production Vincent Pelletier Université Laval Water table control has been successfully tested to improve the sustainability of water management in cranberry production. In the province of Québec (Canada), three sites were investigated to determine the optimum water table depth below soil surface (WTD) using three criteria: 1) increasing yield without decreasing quality, 2) minimizing the amount of water needed by the sprinkler system, and 3) avoiding hypoxic stresses in the rhizosphere. Our results show that the final yield, the berry sugar content, the total number of berries, the number of berries per upright and the fruit set were maximized when the WTD was 60 cm. Sprinkler water savings of 77% were obtained where the WTD was shallower than 66 cm. In order to avoid hypoxic conditions due to poor drainage, the water level in the canals surrounding the beds should be lowered to 80 cm when a rainfall or a frost protection irrigation is anticipated. All sides of a block of beds must be surrounded by canals to ensure a uniform WTD and to avoid lateral hydraulic gradients that could cause peripheral seepage losses. 117 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S17: Soils of Natural, Managed and Intensive Forest Systems/ Les Sols de Systems Forestiers Naturels, Aménagés et Intensifs 118 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Restoring a disturbed clayey forest soil using dehydrated sewage sludge Nutrient and trace metal leaching in boreal and temperate forest soils following wood ash applications Hazlett1, Lili Perreault1, Suzanne Brais1, Nicolas Bélanger2 Basiliko2, Paul Nathan Emma Horrigan3, Honghi Tran4, Trevor Jones5 1 1 Natural Resources Canada, Canadian Forest Service, Great Lakes Forestry Centre 2 Laurentian University, Biology 3 U-Links Centre for Community-Based Research 4 University of Toronto, Chemical Engineering 5 Ontario Ministry of Natural Resources and Forestry Increased bioenergy production will increase wood ash waste production. Currently, wood ash in Canada is commonly landfilled at a cost to energy producers. Forest soil application of wood ash could improve soil fertility, divert materials from landfills and close a loop in the cycling of nutrients during forestry operations. The effect of ash on the leaching of nutrients and trace metals in Canadian forest soils is a knowledge gap that needs to be addressed to assist in the development of sustainable forest management policies for applying wood ash to forests. Wood ash from biomass boilers was applied at two sites in the Boreal Shield and Great Lakes-St Lawrence forest regions. In a jack pine forest at the Island Lake Biomass Harvest Experiment in north-eastern Ontario bottom ash was applied to full-tree harvested plots at four different rates (0, 1.4, 2.8 and 5.6 Mg dry ash ha1). The soil developed in a deep glaciofluvial deposit, is coarse textured with few coarse fragments and a 10 cm thick forest floor. In a maple-beech forest at the Haliburton Forest and Wildlife Reserve in central Ontario bottom and fly ash from a second biomass boiler were applied to selection harvested plots at three different rates (0, 4 and 8 Mg dry ash ha-1). Soils developed in shallow glacial till deposits, are rocky, medium to coarse textured with a 7 cm thick forest floor. Soil solution was sampled using tension lysimeters at 30, 50 and 100 cm depths. Haliburton plots with fly ash additions had higher concentrations of base cations, sulphate and some trace metals at the 30 cm depth compared to plots with no ash. Bottom ash additions at both Haliburton and Island Lake had no significant impact on nutrient or trace metal leaching. 119 | P a g e Université du Québec en Abitibi-Témiscamingue (UQAT), CEF 2 Université du Québec à Montréal (UQAM), Téluq Sewage sludge contains nutrients and organic matter which could benefit forest soils that were adversely impacted by intensive silvicultural activites. Here we investigate the effect of dehydrated sewage sludge application on soil nutrient and contaminant bioavailability, and organic carbon (OC) dynamics over a two-year period in a 9-year old hybrid poplar plantation in Abitibi. The plantation exhibits very low yields due to a clayey soil that was compacted and severely impoverished in surface organic matter by poor harvesting and site preparation practices prior to plantation establishment. Eighteen experimental plots were established to compare natural forest floor and a control to two types of dehydrated sludge (stored 1 and 4 years) applied at two thicknesses (15 and 25 cm). We used Plant Root Simulator™ probes to assess the supply rate of macro- and micronutrients, and of heavy and trace-metals at the soil surface (0-10 cm). We also characterized amendments by determining total OC and total N, C:N ratio, and soil respiration rates (CO2.g1.day-1). Both types of sludge supplied significantly more nitrate and phosphorous but less ammonium to the mineral soil than other treatments. Nitrate and phosphorous supply were slightly higher under the mature sludge. High levels of nitrate could indicate greater nitrification potential in sludge-amended soils. The sludge also supplied more copper, zinc and lead, though metal concentrations remain low. OC and N were significantly higher in the forest floor (25%, 1.13%, respectively) than in the both types of sludge (7.5%, 0.5%), though the sludge had greater CO2 release over OC. This could indicate that surface microbial activity is favoured by less acidic conditions, greater nutrient availability and lower C:N ratios in the sludge. These early results suggest that sludge application could be helpful in restoring the nutrients pool and its processes in disturbed soils, and that the risks associated with metal contamination remain low. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Wood Ash as a Forest Soil Amendment: Seedling growth responses, and responses of red-backed salamander populations Leaf litter and deadwood decomposition in boreal stands as a function of species, litter type and harvesting prescription: A 12-13 year litterbug experiment Adam Gorgolewski1, Nathan Basiliko2, John Caspersen1, Trevor Jones3, Paul Hazlett4, Honghi Tran1 Manuella Strukelj1, Suzanne Brais2, David Paré 1 1 University of Toronto 2 Laurentian University 3 Ministry of Natural Resources and Forestry 4 Natural Resources Canada, Canadian Forest Service Wood ash is a waste product of biomass boilers that is generated in large quantities by forestry industries in North America, and is generally sent to landfills at a cost. Ash has a high pH and nutrient content, and there is growing interest in using ash as a forest soil amendment in eastern North America to rectify ongoing problems of soil acidification and nutrient depletions. However, ash also retains traces of heavy metals and salts which could harm susceptible forest species at high dosages. Ash is commonly applied to forest soils in Eastern Europe, but its effects on native flora and fauna must be assessed before it is approved as a forest soil amendment in Canada. The short-term effects of ash on growth and nutrition of 4 species of tree seedlings native to Canada were assessed in a greenhouse experiment. Ash had relatively neutral effects on seedling growth up to dosages of 10 Mg ha-1, and generally benefited foliar nutrient status. Negative effects were seen at dosages of 15-20 Mg ha-1, and these are expected to be a result of excessive levels of Na salts or metals in the ash. Responses of red-backed salamander (Plethodon cinereus) abundance to ash additions up to 8 Mg ha-1 were also assessed in a field trial. No negative effects of ash were observed, and positive effects on salamander abundance were driven by increases in soil pH and moisture. Further research is necessary before ash can be used widely as a forest soil amendment in Canada, but our studies indicate that it can be beneficial, and does not harm a sensitive indicator species. 120 | P a g e Université du Québec à Montréal (UQAM) Université du Québec en Abitibi-Témiscamingue (UQAT) 3 Centre de foresterie des Laurentides 2 Litter decomposition is a major driver of carbon and nutrient cycling in forest ecosystems. Harvesting is expected to impact decomposition, as it affects litter quality and quantity, microclimate and microorganisms. However, most studies on harvesting impacts have been conducted on leaf litter, over short periods and have produced contradicting outcomes. Also, the single exponential decomposition model that assumes constant decomposition rate and litter quality over time contributes little insights into decomposition dynamics. The objective of this study was to assess the effects of partial and clear-cut harvesting on wood and leaf litter C and N dynamics for three boreal tree species of contrasting litter quality testing a range of decomposition models. A litterbag experiment was conducted over a 12-13-year period within three boreal mixedwoods stand types that were submitted to a range of harvesting prescriptions. Non-linear mixed models were used to describe mass losses and N dynamics. Model selection was based on Akaike’s Information Criterion. A double exponential model better fitted mass loss of aspen, fir and spruce foliage and aspen and spruce wood, whereas the single exponential model better fitted fir wood mass loss. This implies that both fresh leaf and wood contain labile and more recalcitrant components with distinct decomposition rates. Partial and clear-cut harvesting had not effects on mass loss of aspen foliage and wood, and of spruce and fir wood. In contrast, clear-cut harvesting decreased the decomposition rate of the labile component of fir foliage, whereas partial harvesting increased the decay rate of the recalcitrant component of spruce foliage. In relation to unharvested control stands, partial harvesting had no effects on litter N dynamics. Our results imply that slightly more complex decomposition models than the single exponential one can yield better predictions and understanding of C dynamics and sequestration following forest disturbances. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Environment and genotype control on foliar, fine root and litter traits in mature hybrid poplar plantations Forest floor heterogeneity modulates fungal activity and C mineralization in boreal forests Suzanne Brais, Sara Foudyl-Bey, Pascal Drouin Julien Fortier1, Benoit Truax1, Daniel Gagnon2, France Lambert1 Université du Québec à Montréal (UQAM) – Forest Research of the Eastern Townships 2 University of Regina, Biology 1 2 Université du Québec en Abitibi-Témiscamingue (UQAT) Lallemand, Inc. 1 Fine roots and leaf litter make important contributions to soil carbon and nutrient cycling in forests. Yet, little is known about fine root biomass production and leaf litter decay of mature fast-growing tree plantations. In this study, we evaluated different traits of foliage, leaf litter and fine roots of 3 hybrid poplar genotypes (DxN131, MxB-915311 and DNxM-915508) across 3 sites contrasted in terms of elevation (climate) and soil fertility. Plantation environment and poplar genotype had an important effect on leaf litter decay rates over two years. Across sites, elevation was the best predictor of litter mass remaining, despite a strong site effect on several litter chemical traits. At the clone level, litter of DNxM-915508 decomposed more slowly, possibly because of its lower N, P and Ca contents. Despite litter of clone MxB-915311 containing lower N and P than litter of clone DxN-131, they had similar decay trajectories. However, litter Ca of clone MxB-915311 was much higher, which may have stimulated its decomposition. Also, on poorer sites, clone MxB915311 had higher Ca and Mg in its litter than in its foliage, potentially reflecting its strategy of returning base cations to the soil to maintain fertility. From the three clones studied, clone DNxM-915508 was the most efficient and proficient at resorbing N and P from foliage, while having the highest fine root biomass. These traits may be desirable for phytorestoration of agricultural land with excess soil N and P. 121 | P a g e The forest floor of boreal forests is an acid and fungidominated environment where mycelial translocation of C from C- rich litter allows fungi to feed on N- rich but C- poor substrates. The complex geometry of C demand and supply is thus shaped by litters of different quality. Numerous small scale controlled experiments have underlined the capacity of cord-forming fungi to respond to heterogeneous environments. Hence, it is expected that juxtaposition of forest litters of contrasting decay state (high C:N vs low C:N) would alter fungal activity within individual litters. More specifically, fungal biomass and N should preferentially be reallocated to C-rich litters while cellulolytic and ligninolytic enzyme activity should increase in all juxtaposed litters. We tested these hypotheses by conducting a microcosm experiment (n=96) in which wood and leaf litters of two boreal species (Populus tremuloïdes, Pinus banksiana) were incubated alone or in combination with a litter of contrasting decay state. Litter mass loss, change in N content, C mineralization, fungal biomass and specific respiration and cellulolytic and ligninolytic activity were measured after 15 and 30 weeks. Regardless of tree species and litter origin, fungal biomass was initially reallocated to fresh litters when incubated with well decomposed litters. Cellulolytic activity also increased by 30 % in juxtaposed fresh litters while Mn-Peroxydase activity increased by 42 % in both fresh and well decomposed litters when juxtaposed. In the longer term, the N content of juxtaposed fresh litters increased, indicating a transfer from well decomposed litters. Carbon mineralization and specific respiration of fungal biomass increased respectively by 113 and 134 % in juxtaposed well decomposed litters, indicating an increase in overflow metabolism presumably in response to an increase in labile C. Our results underline the functional diversity of the forest floor and its implications for N and C cycles. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Changes in soil conditions and foliar nutrition of sugar maple seedlings with increasing presence of conifers in a mixedwood of Southern Quebec Alexandre Collin1, Christian Bélanger2 Messier1, Overstory and understory functional types drive mineral soil pH, C and N cycles, in mixedwood temperate plantation Vincent Poirier1, Marie Coyea1, Denis Angers2, Alison Munson1 Nicolas 1 Université Laval, Centre for Forest Research Soils and Crops Research and Development Centre, AAFC 1 2 The discipline of ecology suffers from a lack of knowledge to predict forest response to climate change. For instance, migrating species will increasingly interact with new species and cope with completely new soil conditions. In a first field study of three sites forming the largest latitudinal/climatic gradient, we found that sugar maple (Acer saccharum, SM) has a competitive disadvantage for soil nutrients over conifers. We hypothesized that the failure of SM to regenerate is due to interactions with competition and possible feedbacks on soil conditions. An experimental design was thus established in a mixedwood forest located at 80 km north of Montreal. The experimental design was set up in a way to study SM seedlings across a gradient of increasing abundance of conifers until no more regeneration of SM seedlings was found. We tested if soil nutrient availability, soil mineralogy, other soil properties (e.g. temperature, moisture, phenols) and foliar nutrients were impacted with increasing presence of conifers as a means to determine the factors explaining SM regeneration failure. Forests composed mainly of conifers had lower soil moisture, available base cations and pH compared to hardwoods or mixedwoods. Total phenols were higher under stands dominated by conifers. Sequential extractions revealed that the easily weathered Cabearing (e.g. calcite and apatite) and P-bearing (e.g. apatite) minerals were dissolved at a greater rate under conifers, likely due to the long-term acidifying effects. In addition, we found lower foliar Ca and P of SM seedlings under conifers compared to deciduous stands. The results suggest potentially limiting Ca and P availability for SM seedlings under conifers, which could explain regeneration failure. Our results demonstrate the prolonged effects of various forest types on soil conditions and nutrient cycling, and emphasizes the need to consider interactions between species and potential feedbacks to forecast species redistribution under climate change. Forest overstory and understory species composition affect soil organic C (SOC) and nutrient cycling in mineral soil in ways that are still poorly understood, possibly through influences on soil pH and microbial activity. We investigated how disturbance-induced vegetation communities affected surface (0-15 cm) and subsurface (15-40 cm) mineral soil biogeochemistry, 25 years after establishment of white pine (Pinus strobus) plantations. Three silvicultural treatments led to distinct communities, characterized by contrasting structure and functional composition. The control (CTR) was characterized by a Hardwood shrub-rich forest, disturbance by blade-scarification (S) resulted in the development of a Hardwood herb-rich forest, while blade-scarification combined with vegetation control (S+V) resulted in a Conifer monoculture. Increasing dominance of the hardwood canopy was associated with higher surface mineral soil pH, and dominance of net nitrate (NO3--N) over ammonium (NH4+-N) production during incubation, interpreted as an acceleration of soil N cycling with hardwood presence. Higher herbaceous cover was also strongly associated with the same processes, and with increasing ratio of arabinose plus xylose over galactose plus mannose [(A+X)/(G+M)], indicating higher plant-derived neutral sugars. In contrast, increased cover of softwood in the overstory was associated with lower pH of surface mineral soil, lower NH4+-N concentrations, and a decreased contribution of plant-derived neutral sugars. Across all communities, surface mineral soil pH was positively correlated with increases in total N and SOC in the same horizon. In contrast to expectations, the herb cover rather than overstory functional character (hardwood vs softwood) had more effect on N cycling in the subsurface mineral soil; increasing cover was related to higher NH4+-N availability and lower organicto-mineral N ratio, indicating accelerated cycling. We conclude that through effects on soil pH, the cover of hardwood and herbaceous species may strongly regulate N cycling and potential nutrient stocks in the mineral soil of mixedwood forests on acid soils. Université du Québec à Montréal (UQAM) 2 Télé-Université du Québec 122 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Does Bioturbation Control the ChernozemicLuvisolic Boundary in Central Saskatchewan? Dan 1 2 Pennock1, Kendra Purton1, Kent William Barnes1, Sylvie Quideau1, Matthew Swallow2 Watson2 University of Saskatchewan, Soil Science Thompson Rivers University, Natural Resource Sciences The transition between Chernozemic and Luvisolic soils at the northern boundary of the Canadian Prairies is often conceptualized as a gradual shift governed by climatically induced shifts in vegetation. In many places, however, this transition occurs over less than 100 meters, which challenges the existing model. These short-range transitions were examined at several locations along a 50-km transect of soils near Turtleford, Saskatchewan. At each site the Chernozemic soils were located on a convex geomorphic surface composed of a cap of sandy parent materials over till; the Luvisolic soils occurred in lower slope and slight depression features where the till forms the soil surface. There was extensive evidence of faunal bioturbation in the Chernozemic profiles, whereas evidence of bioturbation was largely absent in the Luvisolic profiles. This suggests that the dominant factor controlling the distribution of these soils is the presence or absence of faunal bioturbation, not the vegetation itself. 123 | P a g e Sandy soils of the Athabasca Oil Sands Region: what’s driving productivity? 1 2 University of Alberta, Renewable Resources Mt. Royal Department of Environmental Sciences In the Athabasca Oil Sands Region of NE Alberta, Brunisolic soils developed from sandy parent material are the second most common upland soil type. While these soils are typically very dry, possess poor nutrient regimes and are associated with relatively unproductive Jack Pine-lichen communities, they can also be associated with more productive aspen and white spruce communities with a more diverse array of understory species. However, the processes governing this range of forest community types and their accompanying site productivities are not well understood. To investigate this relationship, we selected twenty sites derived from sandy parent material in an attempt to capture the natural range of variation in forest productivity exhibited by these soil types. Sites were selected to minimize influence of topography, aspect and ground-water table interactions on soil development. Soils were characterized and sampled by morphologic horizon in the field and plant root simulator (PRS) probes were placed to measure available nutrients at the soil surface. In the lab, soil properties measured include texture by the hydrometer method; total and available C, N, and P in the B horizon; pH; EC; CEC; and base cation concentrations. A suite of forest productivity characteristics were also measured within a 100 m2 area surrounding the soil pit, including diameter at breast height (DBH) of all trees; tree height; site index; shrub biomass; and canopy cover using an LAI 2200 plant canopy analyzer from LI-COR Biosciences. Potential relationships between soil and forest properties were explored based on our measured variables. We hypothesize that soil textural discontinuities found in many of the sites are influencing site productivity and canopy type through their alteration of water and nutrient movement through the otherwise sandy soil profile. Types of discontinuities include clay lenses, lenses of naturally occurring oilsands deposits and parent material changes and are thought to have varying degrees of influence on productivity. Given the levels of disturbance occurring in the region, an understanding of the relationship between soil and forest characteristics will aid in the successful reconstruction of the boreal landscape following disturbance. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 1 2 Using historic soil survey data for spruce plantation sustainability assessments – a Nova Scotia case study Recreational fishing may increase greenhouse gas emissions: The earthworm connection Kevin Keys, David Burton Martine Fugère, Robert Bradley, Mark Vellend Nova Scotia Department of Natural Resources Dalhousie University, Environmental Sciences Nutrient management is fundamental to sustainable spruce plantation management where the main goal is to generate increased fibre yields through use of improved growing stock, density management, and competition control. However, given a typical harvest rotation of about 40 years, it is impossible to assess plantation sustainability without the use of nutrient budget models. All nutrient budget models, regardless of their complexity, require soil attribute data that are often derived from soil survey reports. Nova Scotia is one of the few provinces in Canada that has essentially all of its area covered by soil survey, but these surveys are dated and may have an agricultural bias with respect to sample data. To assess the representativeness of historical soil survey data for use in forest nutrient budget models, we sampled 25 spruce plantations on eight soil series in central Nova Scotia. Data collected included pH, percent nitrogen, percent organic matter, exchangeable bases (Ca, Mg, K, Na), effective cation exchange capacity, base saturation, percent clay, bulk density, percent coarse fragments, and rooting depth. We also assessed plantation sustainability using a nutrient budget model initialized with both survey-derived soil data and current, sitespecific soil data. Results showed survey-derived base saturation and nitrogen data to be consistently greater than plantation measured data, whereas the opposite was found for bulk density measures. Results for other soil attributes were mixed. Differences found were likely related to long-term acid deposition impacts, agricultural bias in early soil surveys, and past forest management impacts. There were also differences found in nutrient sustainability assessments using different data sets, with up to 20% of the plantations affected depending on model configuration. Variation in model results were mainly due to differences in base saturation, calcium fraction, and percent clay values between data sets. 124 | P a g e Université de Sherbrooke It’s generally accepted that human activities are the main agents of dispersal for exotic earthworms in Québec, Canada. However, we know little about the effect of human activities on the abundance and assembly of Lumbricidae communities in our forests. In addition, the effect of exotic Lumbricidae on biogeochemical cycles in forest remains unknown. Our first objective was to compare the effects of fishing and the proximity of roads on the abundance and structure of Lumbricidae communities in northern temperate forests. Our second objective was to test whether earthworms could potentially increase the production of nitrous oxide, an important greenhouse gas. We sampled earthworm communities around 61 lakes in Mont-Tremblant National Park, which included 23 heavily-fished lakes and 20 non-fished lakes located near roads, as well as 18 non-fished lakes located in remote areas of the park. Our results revealed that fishing and the proximity to roads both had a positive effect on the abundance of earthworms. The effect of fishing was, however, significantly greater than the effect of road proximity, and this effect increased with soil pH. In addition, fishing was correlated with the abundance of Lumbricus terrestris, an anecic earthworm species. Laboratory soil tests followed by structural equation modeling revealed that the abundance of Lumbricus terrestris reduced soil C:N, which increased soil nitrification and denitrification, two processes that can emit nitrous oxide to the atmosphere. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Tree response to organic-matter removal depends on soil properties at six Long-Term Soil Productivity (LTSP) sites in British Columbia, Canada Anya Reid1, Bill Chapman2, Marty Cindy Prescott1 Kranabetter2, Microbial communities and functioning in boreal forest soil under intensified biomass harvests Emily Smenderovac1, Nathan Basiliko2, Kara Webster3, John Caspersen1, Dave Morris4, Paul Hazlett3, Rob Fleming3 1 1 2 2 Forest managers are responsible for maintaining ecosystem services, such as wood production, after logging. The ability of ecosystems to continue functioning and providing ecosystem services after disturbance is defined as ecosystem resilience. Results over the past 20 years from the Long-Term Soil Productivity (LTSP) project show that the resilience of tree growth to whole-tree harvesting (WTH) and forestfloor removal (FFR) during logging varies between sites, suggesting context-dependent effects. We tested the hypothesis that lodgepole pine resilience to WTH and FFR depends on climate and soil variables known to influence forest productivity using six LTSP sites in the interior of British Columbia, Canada. Resilience of pine growth [tree height (m) and volume (m 3)] and health [vigour and mortality] to WTH and FFR was estimated by response ratios using bole-only harvesting as a baseline. Significant effects of a priori climate and soil variables on tree resilience were tested with redundancy analysis (RDA). Resilience of tree growth to WTH was related to mineral soil pH and base saturation, and mean annual temperature (˚C). Total soil phosphorous (kg/ha) and carbon (kg/ha) increased tree resilience to WTH and FFR. Soil mineralizable nitrogen (kg/ha) increased resilience of tree growth but reduced resilience of tree health to FFR. This suggests that indicators of site sensitivity to biomass harvesting developed from tree growth alone could be misleading. Lodgepole pine growth was more resilient than health at four out of six sites, suggesting success of forest regeneration after logging can be overestimated if only tree growth is considered. Together these results suggest that soil pH, base saturation, carbon, mineralizable N and phosphorus, and mean annual temperature can indicate context-dependent effects of WTH and FFR on forest productivity and that tree health is important to consider. These findings have implications for monitoring the effects of management on forest productivity. Forest biomass use for the purpose of bioenergy production Canada is increasing in popularity as an alternative energy source. Although best practices of conventional forest harvesting and silviculture are considered sustainable, intensification of these practices could introduce and exacerbate existing impacts to ecosystem functioning and sustainability. Microbial communities are key players in forest biogeochemical cycles and ecology. Changes to future ecosystem functioning may be indicated by shifts in microbial community structure. In this study, research plots of jack pine near Chapleau, Ontario, which were differentially harvested with, tree length, full tree, stumped, and bladed clear cut treatments were compared to unharvested control plots, a reference burned site and nearby old-growth forest. Chemical profiles and microbial biomass of soils were assayed to determine influence of harvesting on soil nutrient availability and microbial abundance. Microbial enzyme activities and community-level substrate usage were utilized to compare functional characteristics across the harvested soils. Multiple community fingerprinting approaches (high throughput sequencing and T-RFLP) were used for bacterial 16S and fungal 18S target genes to identify whether harvesting intensity affected microbial community structure. In general, the effect of clear cut harvesting was apparent in chemical, functional and community characteristics of LFH soil. Additional intensification beyond tree-length harvesting did not produce additional changes in any of the soil chemical or biological characteristics measured. Community structure in the natural disturbance fire sites was found to be different from all other treatments examined. This study showed that although clear cut forest soils do not represent natural systems in the short term (1-2 y postharvest) regarding soil microbial community structure and function, intensification of biomass removal beyond tree-length harvesting did not further alter communities. University of British Columbia BC Ministry of Forests, Lands and Natural Resource Operations 125 | P a g e University of Toronto, Forestry Laurentian University, Living with Lakes Centre 3 Canadian Forest Service, Great Lakes Forestry Centre 4 Lakehead University, Natural Resources and Forestry Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Using principal component analysis to link post-harvest soil nutrient decline to latent biogeochemical processes in an Ontario hardwood forest Jason Shabaga1, Nathan Basiliko2, Trevor Jones3 1 University of Toronto Mississauga Laurentian University 3 Ontario Ministry of Natural Resources and Forestry 2 Decomposition of litter and root turnover comprise the primary nutrient input mechanisms for northern hardwood forest soils. Changes to these dynamics from harvesting can potentially alter soil nutrient pools. To understand the effect of harvest intensity on nutrient dynamics, we investigated the impact of conventional tree-length (TL) and more intensive biomass (BIO) harvests on exchangeable soil organic matter (SOM) and nutrients in a Central Ontario hardwood forest. Soils were sampled from LFH and mineral horizons prior to, one, and three years following harvest. Principal component analysis (PCA) was used to evaluate complex relationships amongst variables through dimension reduction, and extracted principal component (PC) scores were assessed for significant changes using mixed models. Partial harvesting significantly decreased dissolved organic carbon and nitrogen (DOC/DON), NH4+, and K (19-46%) by year one in the LFH of TL and BIO treatments, while Mg decreased (16-19%) and Fe increased (8-16%) by year three. Similar, smaller changes occurred in mineral soils, primarily in the TL treatment. PCA of LFH data produced three PCs explaining ≈77% of the variance. PC1 linked SOM, soil moisture, Ca/Mg/K and Fe/Al+, and chiefly represented exchangeable cation pools associated with SOM. Soil moisture, Ca/Mg, NO3-, pH, and % conifer cover loaded on PC2, linking it to moisture regime and vegetation cover, while PC3 was defined by labile compounds (DOC/DON, K/NH4+). Post-harvest scores for PC1 were insignificantly lower in harvested treatments, and a significant decrease to both TL and BIO treatment PC3 and DOC values relative to controls was correlated to increasing soil respiration rates. Mineral soil PCA results were similar but less substantial, indicating that harvesting primarily impacted labile and readily exchangeable nutrients in the LFH horizon. Nutrient decline was likely due to a combination of reduced leaf litter inputs, increased microbial immobilization with elevated decomposition rates, and potential leaching losses. 126 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Poster Sessions Abstracts are displayed by session order 127 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S1: Macro and Micronutrient Dynamics in Soil 128 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Forms of phosphorus in animal manure composts Kinetics of phosphorus forms applied as inorganic and organic amendments during plant growth in a calcareous soil Yuki Audette, Ivan O’Halloran, Paul Voroney University of Guelph The amounts and distribution of various phosphorus fractions (P) in three types of animal manure composts were analyzed by a modified sequential fractionation method. The amounts of total P present in the three animal manure composts varied, but the distribution of the P fractions was similar. A major portion of the manure compost P was extracted with a weak acid extractant (0.5 M NH4Ac, pH 4.2). Animal manure composts contained a large amount of Ca and Mg. Xray diffraction analysis and the model diagram of the stability of the major P minerals for turkey litter compost (TLC) showed that brushite (Ca-P) and newberyite (Mg-P) accounted for the major forms of inorganic P in TLC, and they should be extracted with a weak acid extractant. Both of these inorganic P forms are potential sources of plant available P. Acid soluble organic P, phytates, were also present in TLC, and they are also a potential source of plant available P via enzymatic degradation. Considering almost all P in mineral fertilizer are soluble in water, the forms of P in animal manure composts are clearly different from P forms present in the mineral fertilizers. 129 | P a g e Yuki Audette, Ivan O’Halloran, Paul Voroney University of Guelph Forms of phosphorus (P) present in animal manure composts are different from that in synthetic P fertilizers, which affect how they alter soil P chemistry. The objective of this study was to investigate the effects of inorganic and organic amendments on soil P chemistry during plant growth. The amounts of various P fractions in an unamended control soil and in soils amended with either KH2PO4 or turkey litter compost were measured by a sequential fractionation method during ryegrass growth over a 16-week period in the greenhouse. Uptake of P by ryegrass was from the labile/moderately labile inorganic P forms in soils amended with P, and ryegrass growth promoted mineralization of organic P in the relatively P deficient control soil. Production of plant biomass in the compost-amended soil was significantly greater compared to those in the other treatments after week 4. P applied as inorganic P fertilizer was largely recovered in the labile P extracted with NaHCO3, whereas, the majority of compost-P was recovered in the moderately labile P extracted with NH4Ac. The halflife of the labile/moderately labile P in the compostamended soil was shorter (~193 d) than that in the fertilizer-amended soil (~315 d). The contents of Ca, Mg and organic matter in the compost affected soil P chemistry. The forms of P in the compost may be converted into plant available P through both microbial activity and root-induced acidification in the rhizosphere. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluation of phosphorus bioavailability according to the soil organic matter content – a pot experiment Relationship between soil organic carbon and elements under different intensity management Sophie Barbieux, Malorie Renneson, Gilles Colinet Hana Bilošová, Pavlína Mičová, Hana Landová University of Liège, Gembloux Agro-Bio Tech Phosphorus (P) is an essential nutrient for plants. The organic matter contains significant amounts of P which can be mineralized and supply soil solution. We hypothesize that increasing P organic pools in soils is a way to improve its progressive release for plants and alleviate risks of immobilization in mineral forms. The main objective of this study is to evaluate the P bioavailability and its uptake by plants according to the soil organic matter (SOM) content. The experimental protocol is based on a micro-culture in pots. The testplant used is ryegrass (Lolium perenne L.). Eight silty soils were selected from vegetable gardens (5) and from a long-term fertilization trial on field (3). They present a gradient of SOM (from 2 to 9 %) and available P content (from 5 to 55 mg/100g). Plants were first grown in pure sand and P-free Hoagland nutritive solution. Ten days after plant emergence, roots were brought into contact with the studied soil during about one month. The experiment was stopped after three harvests (every 10 days) and three growth cycles. At the end of the experimentation, analyses were performed on plant material (biomass, P content) and on soil (soluble P, available P, microbial P, pH, phosphatase activity, hot water carbon, nitrate). Besides this study, an incubation experiment was carried out with the same soils without plant to assess soil P status at each harvest time. Paper will present the main findings of the experiment. Especially, the following issues should find answers: (i) do higher levels of SOM and organic phosphorus modify the evolution of P content in soil solution and its uptake by plants?, (ii) are the biological processes involved in P cycling promoted in soils with higher SOM content? 130 | P a g e Agroresearch Rapotín Ltd. The relationship between soil organic carbon and selected elements was studied during the years 2010 and 2011 in the mountain range, in the Czech Republic. Experimental treatments were carried out in natural conditions of permanent grassland, soil type Cambisol. The experiment included three intensity of management varied by stocking rates 0.9 LU/ha (extensive management), 1.4 LU/ha (middle intensive management) and 2.0 LU/ha (intensive management) and control without management. Experimental plots were fertilized by organic (compost and slurry) and by mineral (NPK) fertilizers. Soil organic matter properties were determined as follows: cold water soluble carbon (Ccws, mg/kg), hot water soluble carbon (Chws, mg/kg), oxidizable carbon content (Cox, %). Soil elements were determined as follows: plant available forms - Ca (mg/kg), Mg (mg/kg), P (mg/kg), K (mg/kg), Zn (mg/kg), Cd (mg/kg), Co (mg/kg), Cu (mg/kg) and Ntot (%). Redundancy analysis (Canoco) was used for statistical interpretation. Correlation between Chws, Cox and Mg, N, P was found. No statistical relationship between organic carbon forms and risk elements (Cd, Cu, Zn, Co) was monitored. Greater concentrations of nutrients (N, Ca, Mg, P) and Chws, Cox were measured on plots with middle intensive management. Greater concentrations of risk elements (Co, Cd, Cu, Zn) were measured on the plots with intensive management. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil matrix controls element cycling under alternating redox conditions Effect of raw and alkaline-stabilized biosolids on corn biomass and soil available P in three soils Luisella Celi, Franco Ajmone Marsan, Maria Martin Samantha Halloran1, Mehdi Sharifi1*, Gordon Price2, Chris Metcalfe1, Aime Messiga1 Università degli Studi di Tornio, DISAFA 1 Most soil processes characterizing the biogeochemical cycling of nutrients and pollutants, which have been deeply studied in oxic environments, can be substantially transformed by changing soil redox conditions. Such redox fluctuations may occur naturally or after anthropogenic causes; the latter case is typically represented by paddy rice fields. Alternation of submersion and drying induces subsequent dissolution and precipitation/sorption reactions at the soil solid interface involving redox-sensitive species together with related ones. Most redox reactions in the biogeochemical cycling of C, N and P, microbially mediated, are strongly related to the soil matrix characteristics. In particular Fe oxides, which may promptly undergo redox dissolution, represent one of the main phases controlling the immobilization/release and microbially mediated reactions of nutrients in anaerobic environments. Together with nutrients, also the cycling of contaminants are directly or indirectly affected, so that immobilized forms in oxic soils may become easily bioavailable under reducing conditions and enter the food chain. For instance, paddy rice may become one of the major ways of arsenic intake in human diet. At oxidizing/reducing interfaces with alternating submersion conditions, the composition and equilibria of As forms are strongly controlled by interaction with iron oxides and organic matter dynamics. Changes in the redox environment can have dramatic consequences on heavily contaminated sites, such as mining sites, industrial and urban environments, where different inorganic and organic contaminants are interconverted from immobilized into available forms, depending on their interaction with soil solid phases. Thus, the effect of alternating redox conditions on speciation of nutrients and contaminants is strongly related to the soil matrix which drives element fluxes through soil, water, plant and/or atmosphere. 131 | P a g e 2 Trent University, Environmental & Life Sciences Dept. Dalhousie University, Engineering Alkaline-stabilized biosolids can provide nutrients for crops, particularly P, however their effects on soil P dynamics have not been fully explored. We investigated the effects of primary treated (RB) and alkaline-stabilized biosolids (ATB) on corn biomass and soil P on three soils from different regions. The soils (Mt. Hope and Lindsay, ON; Bible Hill, NS) were amended with six fertility treatments (ATB at 14, 28 and 42 Mg ha-1 dry weight, RB at 42 Mg ha-1 dry weight, inorganic fertilizer (FERT), and control (CONT) with zero P). Corn was seeded into pots in a controlled environment chamber, and above ground biomass was harvested after 10 weeks. Plant dry matter (DM) was measured and plant tissues were analyzed for P concentration. Soil was analyzed for P forms including Olsen P and other properties. Corn DM was highest in all ATB treatments (16% increase of ATB42 over CONT), but was similar between CONT and FERT. Olsen P also increased with ATB, but the extent differed among soils. The highest Olsen P values were obtained with ATB28 and ATB42 for Bible Hill (48.9 mg kg–1) and Lindsay (30.2 mg kg–1), but RB42 (27.7 mg kg–1) at Mt Hope indicating that on these soils, P added with biosolids, rather than plant uptake, controlled soil P changes. Total P across all soils increased with increasing ATB rate, but the highest values were obtained with RB42 (1097-1285 mg kg-1 for the three soils). Soil pH increased with increasing ATB rate only on Bible Hill soil which had the lowest initial pH (6). We conclude that use of treated biosolids can provide high corn DM while maintaining Olsen P and reducing the acidity of low pH soils, indicating that these products can be an alternative nutrient source and lime material. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Sulfur speciation in different sulfur fertilizers applied Saskatchewan soils Preliminary Assessment of Soil Quality in two contrasting Crop Rotations at the Breton Plots, Alberta Gourango Kar, Jeff Schoenau, Derek Peak University of Saskatchewan Sulfur (S) K-edge X-ray absorption near edge structure (XANES) spectroscopy was successfully used for the first time to identify sulfur species formed from S fertilizers in the soil. The synchrotron spectroscopy technique was developed and used to determine S forms present in the seed-row after application of sulfur fertilizers in Saskatchewan soils. Crop grown was canola. Sulfur fertilizers evaluated were ammonium sulfate, gypsum and elemental sulfur and applied in the seed row at rates of 20 kg S ha-1. Urea N fertilizer was broadcast to provide the same rate of N for all treatments at the rate of 100kg N ha-1. XANES spectroscopy showed that after fertilizer application, sulfur species present in the seed-row included the initial forms as well as reduced thiols, oxidized organic S (ester sulfur) presumably originating from microbial assimilation, and inorganic sulfate forms. Overall, the combination of chemical techniques (sulfate extraction) and spectroscopic techniques revealed that different sulfur fertilizer behaved differently and eventually transformed into different sulfur forms. 132 | P a g e Mina Kiani, Guillermo Hernandez Ramirez Agroecosystems Research Group Soil is one of the base resources for agricultural and forage production systems. Sustaining and improving soil quality is essential for supporting short and long term goals of plant productivity and environmental conservation in all terrestrial ecosystems. The aim of this study is to quantify and interpret soil quality variations across a wide variety of land management systems at the Breton Plots Classical long-term experiment. Soil samples were collected in June 2014, encompassing clods and cores from a simple biannual crop rotation, two phases of a complex five-year crop rotation, and an adjacent forest (native vegetation as reference). The soil at the site is a Gray Luvisol. The soil samples are being analyzed using fractal dimension of aggregates for characterizing hierarchical aggregation and soil structure as well as by a water evaporation method after water saturation to describe the pore-size distribution. Soil macroporosity and aggregation are being used as indicators of soil quality and data analyses include mixed and regression models. Implications of soil quality variability will be discussed as a function of agricultural management. In addition, relationships between macroporosity and aggregation versus other soil properties such as texture and soil carbon will be also examined. Results from this study will capture and evaluate the comparative effects of varying plant, soil and nutrient managements on the physical dimension of soil quality in croplands. These findings will subsequently inform the selection of improved approaches for soil quality enhancement in agricultural and forage production systems. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil mineral nitrogen released from the decomposition of green manure crops with different C/N ratios Soil fertility and fertilization practice influenced the transformation and loss risk of reactive N in vegetable greenhouse systems Leonardo Leon Castro, Joann Whalen McGill University, Natural Resource Sciences Green manure crops release soil mineral nitrogen (N), but the quantity and timing of the mineral N release is dependent on a number of factors such as the chemical composition of the residue, climate and soil conditions. The C/N ratio of the residue could be a rapid indicator of a green manure crop’s contribution to the soil N supply in the weeks after it is terminated and incorporated in the soil. The objective of this study was to determine the soil N supply, using ion exchange membranes, derived from field pea (Pisum sativum L.) and oat (Avena sativa L.) mixtures with two C/N ratios in sandy clay loam and sandy loam. This greenhouse experiment was done in pots (10.5 cm diameter by 13 cm depth) containing (1000 g) of sandy clay loam and sandy loam soil. Treatments were no green manure (control), a mixture of field pea-oat green manure with C/N=8 and a mixture of field pea-oat green manure with C/N=12. The soil N supply (soluble NH4-N and NO3-N pools) was assessed weekly with anionic and cationic ion exchange membranes for 6 wks. Greater soil N supply (2.51 µg NO3-N cm-2 week-1) was achieved in the sandy loam mixed with green manure with C/N=8, and the lowest soil N supply (1.57 µg NO3-N cm-2 week1 ) was in the sandy clay loam soil mixed with green manure having C/N=12. This implies that residue chemistry and soil texture influence N mineralization and nitrification processes. The practical outcomes of this work will be to adjust the timing of green manure plowdown as a function of its chemical composition and soil type, to ensure that ample plant-available N is supplied to the next crop planted. 133 | P a g e Caiyan Lu, Yajie Zhao, Yi Shi, Bin Huang, Yongzhuang Wang, Xin Chen Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences Elevated soil fertility level induced by continuous chemical fertilizer/manure application may influence the N loss potential and redistribution within the soilcrop system. A 49-day packed soil column experiment was conducted to evaluate the effects of soil fertility and fertilization treatments on the accumulation and leaching risk of reactive N in the vegetable greenhouse soil. Soil fertility and fertilization treatments significantly affected the accumulation and leaching risk of reactive N in soil. The cumulative leaching losses of total dissolved N (TDN) and dissolved organic N (DON) significantly increased with the increment of soil fertility. Soil fertility had no effect on the cumulative leaching losses of NO3--N. Fertilization significantly increased the cumulative leaching loss of TDN, NO3--N and DON. The majority of TDN in soil leachates existed in the form of DON, averagely accounting for 64.0% among different soil fertility and fertilization treatments. NO3--N correspondingly accounted for 35.1%. The leaching loss of DON occurred mainly within the first 10 days of experiment, and the percentage accounted for 94.7% of total DON loss. These results indicated that DON was an important component of N leaching loss and could be not neglected for the sustainable development of vegetable greenhouse soil. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Seasonal soil mineral nitrogen dynamics and crop yields from a three year field based study using salmon-based silage Phosphorus Substrate Utilization in Wheat and Canola Rhizosphere as determined by Phenotype Microarray during the Growing Season Elizabeth MacCormick1, Gordon Price1, Paul Voroney2, A. Kwabiah3, Marcela A. González1, Shailja Baxi1, Kela Weber2, Carlos M. Monreal1 1 Dalhousie University, Agriculture University of Guelph, Environmental Sciences 3 Agriculture and Agri-Food Canada 2 The Newfoundland and Labrador (NL) aquaculture industry generates over 22,000 metric tonnes of finfish each year. Recently there has been a growing awareness for the potential economic, social, and environmental impacts of utilizing fishery by-products. The salmon industry in NL estimates that approximately 10% of salmon stock grown in pens will die before reaching production. A three year field study was conducted at two locations in St. John’s, NL with annual ryegrass (Lolium multiflorum) and corn (Zea mays). Four fish silage rates, applied on the basis of total nitrogen, were compared to a recommended chemical fertilizer application rate at both research sites. Corn and annual ryegrass yields were measured annually, and soil mineral nitrogen dynamics and other soil chemical parameters were characterized through each season. Results suggest that fish silage can provide a locally sourced soil amendment comparable in both soil mineral nitrogen and crop yields to the recommended chemical fertilizer rate, contributing to food security and sustainable industry practices in the province. 134 | P a g e 1 Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Canada. 2 Department of Chemistry and Chemical Engineering, Royal Military College of Canada Little is known about the microbial utilization and mineralization of phosphorus (P) substrates in crop rhizospheres. Soil microorganisms influence plant productivity by solubilising and mineralizing soil organic-P (Po). A greenhouse experiment was carried out to study the microbial utilization of 59 P-substrates in a Melanic Brunisol planted to wheat (Triticum aestivum) and canola (Brassica napus). Substrate utilization dynamics during the growing season of both crop rhizospheres was determined using BIOLOG’s Phenotype MicroArrays (PM4) system. Four replicated treatments were established: soil alone; soil + crop (unfertilized); soil + crop + fertilizer-N; soil + crop + fertilizer-N-P. Principal component analysis of transformed absorbance data indicated that a number of key Pcontaining substrates discriminated the effects of treatment, growth stage and crop type. For example, in wheat, the substrates adenosine-2’,3’-cyclic monophosphate, adenosine-3’,5’-cyclic monophosphate, D-glucosamine-6-phosphate and several hypophosphites, such as, phosphate, phosphoryl choline, tripolyphosphate were shown to be key discriminators. In canola, discriminating substrates included cytidine-3’,5’-cyclic monophosphate, thiophosphate, triethylphosphate, O-phosphorylethanolamine, D-glucose-6-phosphate and phosphoryl choline. This information contributes to increased understanding of the soil microbial utilization of Pcontaining substrates regulating P-cycling in crop rhizospheres. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial Utilization of Substrates in Canola Rhizosphere Are legume crops beneficial on soil productivity and N supply in cold eastern Canada? Mahdi Najem1, Marcela González2, Shailja Baxi2, Kela Weber3 Carlos Monreal2 Adrien N’Dayegamiye1, Caroline Côté1, Gilles Tremblay2, Joann Whalen3 1 Carleton University, Biology Agriculture and Agri-Food Canada 3 Royal Military College 2 Increasing nutrient use efficiency by crops requires new knowledge on the microbial metabolism of organic substrates in the solution of crop rhizosphere. The advent of new biochemical methods, such as Biolog® Ecoplates, can help to better understand the microbial metabolism of carbon (C) and nitrogen (N) in soil-crop rhizhospheres. We used Biolog® Ecoplates to determine the utilization of 31 carbon and nitrogen containing substrates by soil microorganisms in a Melanic Brunisol planted to canola (Brassica napus) rhizhosphere under 4 treatments: soil alone; soil + canola (unfertilized); soil + canola + fertilizer-N; soil + canola + fertilizer-N-P. Changes in C and N substrate utilization were observed between unplanted soil and canola planted soil. In addition, microbial substrate utilization was significantly affected by the presence of canola plants, and the addition of N- and P-fertilizers. Discriminant together with Factorial/Principal Component Analysis showed that succinic and pyruvic acid derivatives, Lthreonine, phenylalanine and putrescine contributed most to discriminating the effects of treatment. Crop phenology influenced substrate metabolism during the growing season. Substrates such as glycogen and Dxylose, α-ketobutyric acid and 4-hydrobenzoic acid Lthreonine and phenylethyl-amine contributed most to discriminating the effects of growth stage. 135 | P a g e 1 Research and Development Institute for the AgroEnvironment (IRDA) 2 Centre de Recherche sur les Grains (CEROM) 3 McGill University, Natural Resource Sciences This study was conducted in two different climatic regions to evaluate 12 legume crop benefits on yields, N nutrition, corn, and wheat N response and on soil properties. Four of the twelve legume systems studied (alfalfa, hairy vetch, crimson clover and hairy vetch/wheat) were high-yielding (3 to 6 Mg dry matter ha-1) and N-rich (50 to 134 kg N ha-1). These four legume systems also increased yields and N nutrition of corn and wheat at St Mathieu-de-Beloeil site and of wheat only at St Lambert-de-Lévis. Also, soil macroaggregates, aggregate MWD, phosphatase alkaline and dehydrogenase activity were increased following the above-cited legumes at St Mathieu-de Beloeil site only. Benefits of preceding legume crops on soil properties and on crop yields, N nutrition and N use efficiency were more noticeable at warmer site than at cooler location, probably due to better conditions for crop growth and residue mineralization. Greatest N fertilizer replacement value for subsequent corn (37 to 77 kg N ha-1) and wheat (5 to 37 kg N ha-1) were obtained for these same legume crops, although N credit for those legumes was less than 30 kg N ha-1. This implies that the non-N effects of these legume crops such as stimulation of enzyme activity and soil aggregation exerted an important positive effect on grain crop yield and N nutrition. Our results show that under warm climatic conditions, including forage legume crops in the rotation can provide a direct N contribution and indirect benefits to crops by improving soil fertility. Therefore grain crop yield and N nutrition are expected to improve in the years following forage legume crops, which should encourage agricultural producers to include legumes in their crop rotations. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Potassium Dynamics in Sandy Soils Under Potato Crop Soil Nutrients as Affected by Three Years of Tillage, Crop Rotation and Cover Crop Management Chaima Nechi1, Athyna Cambouris2, LéonÉtienne Parent1 1 2 Laval University Agriculture and Agri-Food Canada Quantification of nutrient movement from agricultural soils is important for both fertilizer and environmental management. This study evaluated the effect of K fertilization on the K dynamics. Each year (2013 and 2014), two sites were established on commercial field used for potato production located near Quebec City, Canada. The texture of the soil surface was loamy sand and soil series were Orléans, Saint-Nicolas and Pont-Rouge. The experiments comprised three replications and eight treatments. The K was applied at five rates (0, 70, 105, 140, 210 kg K ha-1) as a combination of potassium chloride and SulPo-Mag; there were three rates of calcium (15, 125, 250 kg Ca ha-1) applied as calcium sulphate. The soil solution was sampled biweekly from planting to harvest (8-9 sampling periods per site) using suction lysimeters and the concentrations of the soil solution K (SSK), Ca (SSCa) and Mg (SSMg) were measured. For both years, no significant difference between treatments on SSK was observed unlike sampling periods: the K leaching pattern differed between sites. In 2013, the highest SSK concentration was observed 16 days after planting (DAP), at Pont-Rouge (47 ppm). Thereafter (till 57 DAP), there were no significant differences. From 72 DAP on, SSK declined. At Orléans, SSK slightly increased until 78 DAP, followed by a decline till the end of the growing season. In 2014, there were no significant differences till 43 DAP, before SSK decreased till the end of the growing season at Saint-Nicolas. At Pont-Rouge, SSK increased until 43 DAP (87 ppm), followed by a decline. For all the sites, SSCa and SSMg were significantly influenced by the treatments, the sampling period or by their interaction. Those results suggest that the addition of K influences SSCa and SSMg and that the pattern of K leaching is soil-specific. 136 | P a g e Nkongolo, Nsalambi1, Samuel Haruna2 1 Lincoln University of Missouri, Agriculture and Environmental Sciences 2 University of Missouri-Columbia, Soils, Environmental and Atmospheric Sciences Agricultural management practices of tillage, cover crop and rotation were introduced to improve nutrient turnover and crop yield. We studied the effects of three years of tillage, cover crop and crop rotation on selected soil nutrients. Twenty four plots of each corn (Zea mays) and soybean (Glycine max) were established on a 4.05 ha field and arranged in a 3factor factorial design with 3 replications. The 3 factors (treatments) were two levels of tillage (no-tillage vs moldboard (conventional] tillage), two levels of cover crop (no-rye vs rye) and four levels of rotation (continuous corn, continuous soybean, corn/soybean, and soybean/corn rotations). Soil samples were taken each year at four different depths in each plot; 0-10 cm, 10-20 cm, 20-40 cm and 40-60 cm and analyzed in a commercial laboratory for soil chemical properties and nutrients. Macro nutrients analyzed include calcium (Ca2+), magnesium (Mg2+), nitrogen (NO3- and NH4+), potassium (K+), phosphorus (H2PO4-), Sulfur (SO42-), and sodium (Na2+) while micro nutrients analyzed were iron (Fe2+), manganese (Mn2+), copper (Cu2+) and zinc (Zn2+). Results in the first year showed that tillage improved NO3- levels by 40%. In the second year, there were significant interactions between crop rotation and tillage for NH4+ (p < 0.05) and between tillage, cover crop and crop rotation for Fe2+ (p < 0.05). In the third year, significant interactions included cover crop x crop rotation for K+ and H2PO4- (p < 0.01), cover crop x crop rotation x tillage for Zn+ (p < 0.05). We conclude these management practices affected soil chemical properties. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Predicting Phosphate Adsorption by Agricultural Soils using the Component Additivity Approach and the Constant Capacitance Model Nowell1, Vickers1, Peter Stephanie Leslie Evans1, Douglas Aspinall2, Stewart Sweeney2 1 2 University of Guelph, Environmental Sciences Ontario Ministry of Agriculture, Food and Rural Affairs Non-point source phosphorus (P) loading to the Great Lakes has been identified as a significant contributor to the eutrophication of these water bodies. Management of agricultural cropping systems is one strategy to mitigate the export of non-point source P to receiving waters. Understanding the chemistry of soil P, particularly how it differs from soil to soil in agricultural landscapes is essential to guide on-farm decision making. In this study, a component additivity approach was used to predict the adsorption of phosphate by clay and oxide minerals found within southern Ontario agricultural soils. A chemical model was developed that considers aqueous phosphate speciation, precipitation of secondary phosphate minerals, and phosphate adsorption by the surfaces of the clay mineral assemblage and the Fe-oxides present in soils from the Rondeau Bay watershed. This model was written in Visual Basic. Clay mineral surface acidity constants were determined by potentiometric titration whilst goethite binding constants were obtained from the literature. Phosphate adsorption by clay minerals was investigated through a series of batch adsorption experiments at varying pH while phosphate concentration, ionic strength, clay suspension density, and temperature were held constant. Parameters used in the constant capacitance model, a chemical surface complexation model, to describe the adsorption of phosphate by clay minerals were optimized from the clay batch adsorption data using the software program FITEQL. Parameters that describe the adsorption of phosphate by goethite were taken from the literature. The resultant soil assemblage model was used to predict phosphate adsorption by the clay minerals and Fe-oxides characteristic of the agricultural soils within the study area. Soil batch adsorption experiments were carried out to test the model's efficacy. Study results will contribute to a broader geospatial P sensitivity mapping effort and guide management system development for Ontario's agricultural soil landscapes. 137 | P a g e Critical phosphorus concentrations and P saturation ratio levels under potato production in Atlantic Canada Judith Nyiraneza1, Rim Benjannet2, Keith Fuller3, Benoit Bizimungu4, Gary Bishop5, Lotfi Khiari2, Yefang Jiang6, Mark Grimmett6, Vernon Rodd6 1 Agriculture and Agri-Food Canada Université Laval 3 Atlantic Food and Horticulture Research Centre 4 Potato Research Centre, AAFC 5 Atlantic Cool Climate Crop Research Centre, AAFC 6 Crop and Livestock Research Centre, AAFC 2 Phosphorus is the second most limiting nutrient in crop production after nitrogen. In Atlantic Canada, most of the soils cropped to potatoes (Solanum tuberosum L.) test high to high plus for soil P extracted with Mehlich3 (P-M3) solution based on local ratings. There is a need to identify potato response to P fertilization to ensure optimum P production while minimizing the risk of soil P buildup. This ongoing study (2013-2016) evaluated potato response to increasing P fertilizer in Prince Edward Island, New Brunswick, Nova Scotia and Newfoundland. Field experiments were conducted during two growing seasons in in 2013 (13 sites) and 2014 (14 sites) on soils with contrasting P-M3 levels ranging from 42 to 295 mg P kg-1 soil. Phosphorus rate effects were significant only on 25 and 35% of the sites in 2013 and 2014, respectively. Relative yields (yield in the treatment over maximum yield) at different sites ranged from 35 to 99%. Relative yields of the two years were pooled together and plotted against initial P concentrations, P saturation ratios [(P/Al), and P/Al+Fe)], and critical levels were identified using the iterative Cate-Nelson procedure to partition responsive and non-responsive sites. Critical soil P-M3 concentrations were 79 mg kg-1, 8 for P/Al, and 7 for P/(Al+Fe). Our preliminary results provide new insight into soil P levels above which potato response to P fertilization is expected to be unlikely. Current P fertilization rates may need to be revised to mitigate the risk of soil P saturation. Field trials will continue in 2015 growing season to validate these findings. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Availability of inorganic phosphorus fraction in soil amended with cow manure Competitive interaction of selenium and phosphorus in wheat (Triticum aestivum L.) Cecilia Paredes, Rolando Demanet, Mariluz Mora, Leyla Parra1, Nuria Ferrol2, Cecilia Paredes1, Marjorie Reyes-Diaz1, Claudio InostrozaBlancheteau1, Maria de la Luz Mora1 Universidad de la Frontera 1 The Chilean Andisols are of great importance in the economy of southern Chile supporting the bulk of agricultural production. The major characteristics of Chilean volcanic soils are the high adsorption capacity of P with a concomitant low P availability to plants. Studies preliminary using dairy cattle dung suggest that we can improve P availability using organic P sources within the soil because of microorganism. Phosphorous solubilization by microorganisms is a complex phenomenon, which depends on many factors such as nutritional, physiological and growth condition of the culture. The principal mechanism for mineral phosphate solubilization is the production of organic acids where the enzyme phosphatases play a major role in the mineralization of organic phosphorous in soil. The objective of this study was to evaluate changes in soil phosphorus fractions due to application the cattle dung, glucose, nitrogen (N) and phosphorus (P). In this experiment we incubated soil samples with 300 g of cattle dung, 30 mg kg-1 of N and P and 1000 mg glucose kg-1. The soil samples were moistened to field capacity and incubated in plastic bags to room temperature by different time. The changes in P forms in soil were monitored through the Hedley fractionation procedure and phosphatase activity. Our preliminary results indicated that the application of cattle dung, glucose nitrogen and phosphorus, caused the increased phosphatase activity until to 7 days and then apparently return to normal values. Interestingly, we observed a rise in the inorganic P fraction extracted by NaHCO3 in the same period. In summary, the increase biological activity by carbon and nitrogen increase P availability. 138 | P a g e Universidad de la Frontera, Center of Plant, Soil Interaction and Natural Resources Biotechnology 2 Departamento de Microbiología del Suelo y Sistemas Simbióticos Selenium (Se) is an essential micronutrient for animal and human health. The selenite in acid soils is poorly mobile, because of its high degree of adsorption on mineral surfaces and soil organic matter. We know that phosphate and selenite has similar adsorption mechanisms in soils resulting in a competitive effect on active sites of soil. The Se uptake in plant tissues is also affected by competitive anions because both nutrient could be transported by the same channel. Therefore, our experiments are conducted to elucidate the interaction between selenite (Se) and phosphorus (P) and its effects on lipid peroxidation and expression of phosphate transporter gene (TaPT8 and TaPHT2;1) in wheat. Different Se (0, 30 and 60 µM) and P (100 and 300 ppm) doses and their respective combination were used in a nutrient solution on 24, 72 h and 7 d. Lipid peroxidation was evaluated by TBARS assay and gene expression analyses, through qRT-PCR. In general, higher concentration of Se was observed in roots than in leaves. The major Se differences are observed on 7 d in both tissues. The application of P did not change the Se concentration in leaves; however, the highest P rate decreased Se concentration in roots. Damage to the biological membrane occurred after 24 h in roots and leaves. On the other hand, TaPT8 transporter was expressed mainly at 72 h in all Se treatment with 100 ppm P. At the highest P doses (300 ppm), gene expression of TaPT8 was markedly decreased with the highest Se concentrations. These results suggest that the first TaPT8 phosphate transporter gene could be involved in Se uptake of roots. Finally, TaPHT2;1 could participate in the Se transport in leaves, although more studies are necessary to confirm these assumptions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of interseeding cover crops on corn biomass and nitrogen requirement Chengyin Pei1, Mehdi Sharifi2, Barry Saville3, Chantal Hamel4 1 Trent University, Environmental Life and Sciences Trent University, Environmental and Resource Studies 3 Trent University, Forensic Science 4 Semiarid Prairie Agricultural Research Centre, AAFC 2 Interseeding cover crops (CC) in grain corn offers an opportunity to improve the sustainability of corn production systems in cool humid region of Canada. The objective of this study was to investigate the effect of CC species, N fertilizer rate and AMF inoculation on corn biomass and N uptake. Cover crop treatments include red clover, microclover, hairy vetch, bush bean and control (no CC). Soil was pasteurized at 80°C for 40 mins before planting, half of which was inoculated by AMF (G. intraradise) and the other half were noninoculated. Rectangular pots (66 cm length * 24 cm width) with field soil were used in the greenhouse (2427°C, 16 h daylight) experiment. Two N fertilizer rates (10 and 80 kgN ha-1) were applied. Corn and legume aboveground dry biomass were measured 7 weeks after seeding. Results indicated CC species was the main factor that influenced corn dry biomass. Within CC treatments, lower corn biomass were measured in bean (42.37g pot-1) and in vetch (48.05 g pot-1) compared with control (79.4 g pot-1). No significant differences were found between the two clover species and control. Bean and vetch dry biomass were 7.3 and 3.5 times higher than the red clover biomass (5.3 g pot1). High N rate negatively (p < 0.05) impacted the biomass of bean but not the other cover crops. Corn N uptake in control and two clover treatments were significantly higher than that in vetch and bean treatments. However, vetch and bean N content at harvested stage were significantly higher than two clovers. Higher N rate resulted in a better N uptake for both CC and corn. Overall, more serious competition between cover crops and corn was shown when interseeding corn with bean or vetch than clovers. 139 | P a g e Changes in phosphorus-fractions and phosphate-activity in ryegrass with two different phosphorus sources Patricia Poblete, Nicole Montalbán, Yonathan Redel, Maria de la Luz Mora Universidad de la Frontera Andisols under grasslands, whom may contain 50-84% of total phosphorus (Pt) in organic form (Po) after the mineralization, could contribute significantly to phosphorus (P) for plant nutrition. The efficiency of P use by plants from soil and fertilizer sources is often low, despite that many soils contain a relatively high amount of total P which is sparingly available to plants. The aim of this work was to assess the phosphorus change in soil fractions and P-ase activity in rhizosphere of growing ryegrass plants in rhizobox system fertilized with two different phosphate sources. Assay was established with perennial ryegrass plants in rhizobox system in greenhouse conditions. The treatments were: triple superphosphate (TSP), phosphoric rock (PR) and plants without P as control. After 90 days roots and rhizosphere soil were sampling removed carefully from rhizobox. The effect of the phosphate source in the dynamic pool of P we used the chemical fractionation method described by Hedley. Olsen P increased in the rhizosphere soil, this is related to the P-ase activity results which showed a decreased activity in roots and rhizosphere soil in treatments compared with control. The lowest extractable P was found in the NaHCO3 fraction. NaOH-Po extractable fraction was the highest with all treatments. With TSP, NaOH-Pi and HCl-Pi was higher than the Po, this phenomenon also occurs with HCl-Pi in control. PR showed an increased to 65% in HCl-Po and 33% in HCl-Pt compared with control. Po content was increased with both sources of P representing 55% of Pt with PR and ~ 53% of the Pt with control and TSP. When ryegrass plants are fertilized with phosphate sources a mobilization of soil P occurs in soil and decreased its P-ase activity because this strategy is used by plants in conditions of low P for its development. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 1 2 Nutrient release during litter decomposition in cold temperate forest: effects on the limitation of asymbiotic N2-fixation Crop yield and nutrient uptake response to different rates and frequency of alkaline treated biosolid applications Nina Pourhassan1, Sebastien Bruno1, Mark Davidson Jewell2, Bill Shipley2, Jean-Philippe Bellenger1 Gordon Price, T. Astatkie Université de Sherbrooke, Centre Sève, Chimie Université de Sherbrooke, Biologie Mo limitation of asymbiotic N2 fixation has been reported in most ecosystems from tropical to boreal. However, the mechanisms leading to Mo limitation in natural habitats remain elusive. Recently, a study in cold temperate forests showed that Mo and P limitation of asymbiotic N2 fixation is strongly influenced by the vegetative cover and is characterized by a seasonal variability. P and Mo limitation was observed only in coniferous litter. P limitation is expressed in early growing season while Mo limitation appears in late growing season. It has been hypothesized that the quality of the litter and the decomposition dynamics plays an important role in the emergence of Mo limitation. Here, we measured nutrient concentrations (P, Mo and others) during litter decomposition in various deciduous and coniferous litters and their combinations (2 and 4 species) using litter bags. Results confirmed that deciduous litter achieve higher nutrient contents (P and metals) and decomposed much faster than coniferous litter. They also confirmed that the concentration of most elements increased with decomposition (Fe, V, Al, Ti, Cu, Co, Mn and Zn), with the exception of P and Mg which decreased in both litter types. The concentration of Mo also significantly decreased with decomposition in coniferous litter. As previously described, we observed that the absolute content of most metals (except Mo in coniferous litter) increased with decomposition, suggesting that the litter can concentrate metals from the surrounding (i.e. soil and atmospheric deposition). These results comfort the hypotheses that litter quality and nutrient dynamics during litter decomposition plays an important role in P and Mo limitation of asymbiotic N2 fixation. 140 | P a g e Dalhousie University, Engineering A field study examining the effect of application frequency (annual or single) and increasing rates of an alkaline treated biosolid (ATB) on corn yield and nutrient uptake was established at the BioEnvironmental Engineering Centre (BEEC), Faculty of Agriculture, Dalhousie University. The treatment plots were established to continuous corn production from 2009, after a prior crop of soybeans, until 2012. The study was established in a split plot design with two management practices (MP) as the whole plot, consisting of annual ATB applications from 2009 to 2012 and a single ATB application in 2009. The subplots were assigned to the biosolid treatments consisting of five ATB application rates (0, 7, 14, 28 and 42 Mg ha-1), as well as a treatment based on a recommended lime rate and an unamended soil control. The experimental design was a randomized complete block design (RCBD) in 2009, and subsequently split plot with two levels of management practice and six rates. Corn biomass and grain yields, as well as N and P uptake, were measured annually from 2009 to 2012 and compared based on ATB rates and management practice. Corn yields were significantly increased over the entire study period at rates >14 Mg ha-1 under annual ATB applications but not under a single application. Corresponding N and P uptake in the corn grain and biomass also followed the same pattern, with average uptake being 40% greater under annual applications than the single ATB application. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Rhizosphere phosphorus availability as affected by Al, Fe and Si content in volcanic grassland soils Redel1, Naomi Robbins1, Yefang Jiang2, Judith Nyiranez2, Michael van den Heuvel1, Christine Noronha2 Cartes1, Yonathan Paula Gabriela Velazquez1, Patricia Poblete-Grant1, Roland Bol2, Rolando Demante1, Maria de la Luz Mora1 1 Universidad de la Frontera, Scientific and Technological Bioresource Nucleus 2 Institute of Bio- and Geosciences, IBG-3 Agrosphere Volcanic ash derived soils, represents between 5060% of the total arable land area of southern of Chile. In these soils, high inorganic P fixation and, in turn, low P availability, and high Al soluble concentrations (at low pH) are the most important limiting factors in crop production. The aim of this work was asses the influence of Al, Fe and Si contents in four volcanic grassland soils with respect to rhizosphere phosphorus availability. We used an chemical sequential extraction procedure (Hedley) for determining the role of different extractable soil Pi and Po fractions, assuming the fractions follow a decreasing gradient of plant availability, and also we determined total P, Olsen P, microbial P in rhizospheric and bulk samples in four Andisols of southern Chile. Also we used oxalate and pyrophosphate to determine the active and organic matter complexes of Al, Fe and Si. Furthermore, we quantified Al, Fe and Si in extracts of the Hedley P fractions. We found that total P, and in general, Pi fractions followed the gradient Gorbea < Piedras Negras < Pemehue < Llastuco soil series, as consequence of increasing amounts of excretal P return from cattle under the different grazing intensities. We have found that Al and Si plays the most important role in negatively affecting P availability, probably due Al silicate–Po complexes which were correlated with the overall Po accumulation. Organic matter bound Fe enhanced P mineralization and thereby depleting P fractions. We determined that rhizosphere P was reduced 20% respect to bulk soils. In rhizosphere soils, Al, Fe and Si contents were closer related with P availability than in the bulk soil, and an higher proportion of Al and Fe was found linked to the organic P fractions likely a plant strategy prevent Al toxicity 141 | P a g e Effects of Buckwheat as a Potato Rotation Crop on Soil and Water Quality 1 University of PEI, Canadian Rivers Institute Agriculture and Agri-Food Canada, Charlottetown 2 Potato production plays a significant role in the economy in Prince Edward Island (PEI). However, high levels of nitrogen losses from the potato production systems have been linked to the contamination of groundwater and associated surface water. While the industry is facing unprecedented pressure to mitigate the environmental impacts while maintaining its market competitiveness, it is also being threatened by increased wireworm damage to potatoes. Buckwheat has been shown to have biofumigant effects on wireworm. Five three-year potato rotations were planted in 2014, including two current industry standards: barley underseeded with red clover B(RC)/RC/P (T1), and barley underseeded to timothy B(T)/T/P (T2) which are compared to buckwheat-based cropping systems each consisting of two years of buckwheat, but with different crop termination methods. Buckwheat terminated midseason through mowing Bw/Bw/P (T3), buckwheat terminated through disking Bw/Bw/P (T4) and buckwheat grown for grain Bw/Bw/P (T5). Steel lysimeters (21) and soil piezometers (12) were installed, and sampled weekly when the soil is saturated and/or after each rain event to measure concentrations of nitrogen & phosphorus. Soil samples were collected from the root zone (0-15 cm), plowpan (15-30 cm) and the unsaturated zone (30-45 cm). Nitrogen and carbon mineralization will be assessed on sampled soils. Anion Exchange Membranes (AEMs) were replaced monthly to measure nitrate. Long term projections of nitrate leaching will be executed using LEACHN. Preliminary soil water nitrate measurements from 2014 showed higher time-averaged concentrations in T#4 (11.4 mg N/L, ±6.1) and lower in T#5 (3.8 mg N/L, ±1.7). AEMs data showed a similar trend towards lower nitrate under T#5 with 0.28 mg N/cm2 /d. Nitrogen released after two-week soil incubation, and CO2 released after 24 hours will be presented. This study will show if growing buckwheat as a rotation crop improves water and soil quality compared to the industry standard rotation systems. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soils contaminated with trace metals for the production of bioenergy from biomass Isabelle Royer, Athyna Cambouris, Annie Claessens, Denis Angers, Noura Ziadi and Isabelle Perron Agriculture and Agri-Food Canada In Canada, there is a large number of trace metal contaminated sites, which cannot be used for human or animal food production. Using these sites for the production of dedicated energy crops could represent a sustainable alternative to the use of good quality agricultural soils. Switchgrass (Panicum virgatum L.) and reed canary grass (Phalaris arundinacea L.) are increasingly studied to determine their potential as energy crops. This project aims at developing a sustainable biomass production system based on the production of these species on trace metal contaminated lands under the climatic conditions of eastern Canada. The 0.7-ha site is a former incinerator located near Québec City (46°44′39.16′′N - 71°10′30.01′′N). In order to design the experimental layout, the spatial variability of the site was investigated using a 6.5-m triangular grid. On each point (n=200), the soil was sampled at 020-cm depth. The highest concentrations of Cu, Pb and Zn determined at the site were 1280, 3317, and 9256 mg kg-1, respectively. The soil texture varied from clay to loamy coarse sand. The clay content varied between 63 to 444 g kg-1 (mean = 153 g kg-1). The pH varied from 5.5 to 8.3 (mean = 7.4) and the soil total carbon varied between 3.2 to 70 g kg-1 (mean = 23.7 g kg-1). Using the B criteria level of Cu, from the Soil protection and rehabilitation of contaminated sites policy two different zones were delineated i.e. Z1 < 100 and Z2 ≥ 100 ppm. A randomized complete block design with four replicates for a total of 8 plots was established in spring 2015 to assess the yield potential and the quality of the biomass produced. This project will contribute to increase our knowledge on sustainable production systems of bioenergy perennial crops on contaminated soil under the conditions of eastern Canada. 142 | P a g e Low molecular weight organic acids reduce inorganic phosphorus adsorbed in biocarbonate-extractable and Fe/Al-bound soil fractions Yi Shi, Yongzhuang Wang, Xin Chen, Yanhong Cao, Bin Huang, Muqiu Zhao, Caiyan Lu, Yi Shi University of Chinese Academy of Sciences, Forest and Soil Ecology Exudation of low molecular weight organic acids (LMWOAs) from plant roots enhances phosphorus (P) acquisition from soil, either by dissolving P fixed in secondary minerals or by reducing P adsorption to organo-minerals. How LMWOAs may modify P adsorption in soils with contrasting pH is not well understood, much less the mechanisms involved. The effects of three common LMWOAs (oxalic, citric and malic acids) on P adsorption in calcareous, neutral and acidic soils were studied in batch experiments, followed by sequential P fractionation to elucidate the mechanisms whereby LMWOAs alter P adsorption. The adsorption data of the three soils fitted better to Freundlich equation (r2 = 0.325-0.994, P < 0.05) than the Langmuir and linear equations. Oxalic, citric and malic acids at 10 mmol kg-1 soil decreased Freundlich P adsorption parameters Kf and n, which represent P adsorption capacity and energy, due to the fact that LMWOAs reduced P adsorption in NaHCO3-Pi (soil soluble and exchangeable Pi, 23.8-30.9%) and NaOHPi (Fe/Al-Pi, 21.6-54.2%) fractions of the three soils. Comparing acidified P-LMWOAs solutions with the pHadjusted P-LMWOAs solutions (pH=7) had a minor effect on P adsorption. Our results indicated that the reduction in soil P adsorption was due to ligand exchange and chelation of LMWOAs with Fe/Al minerals, and the acid strength of LMWOAs had a minor effect on P adsorption in calcareous, neutral and acid soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Net nitrogen mineralization enhanced with the addition of nitrogen-rich particulate organic matter Short-term nitrogen dynamics in response to five rates of poultry litter with woodchip bedding Mervin St. Luce, Joann Whalen, Noura Ziadi1, Bernie Zebarth3, Ben Thomas1, Joann Whalen1, Mehdi Sharifi2 1 Soils and Crops Research and Development Centre, AAFC 2 McGill University, Natural Resource Sciences 3 Potato Research Centre, AAFC Particulate organic matter (POM) is a labile fraction of soil organic matter (SOM) that could contribute to nitrogen (N) mineralization. We added native and nonnative POM to whole soils (WS) with contrasting soil properties and assessed net N mineralization during a 28 d incubation study. Whole soils (0-15 cm depth) were collected from a clay soil with a 3-yr history of corn (Zea mays L.), a loam soil with a 2-yr history of alfalfa (Medicago sativa L.) and sandy-loam and silty-clayloam soils that were cropped in the previous 5 yrs with a corn-soybean (Glycine max L.) -corn-forage-forage [45% alfalfa + 55% timothy (Phleum pratense L.)] and corn-soybean-forage-forage-forage rotation, respectively. The POM was separated by size fractionation (> 53 µm) from coarsely sieved (> 6 mm) soil. The N concentration in POM followed the order loam > silty-clay-loam > clay > sandy-loam, whereas the lignin concentration was the reverse. Compared to WS, addition of N-rich POM from the loam soil increased net N mineralization in the clay soil and gave similar net N mineralization in other soils, while addition of N-poor POM from the sandy-loam soil resulted in lower net N mineralization in the loam and silty-clayloam soils. Multiple stepwise regression analysis showed that net N mineralized due to POM addition was related to the N concentration in POM (partial R2 = 0.54) and initial soil mineral N concentration (partial R2 = 0.33), suggesting that N mineralized from POM was related more to POM chemical composition than soil properties. We propose that information on POM chemistry in conjunction with soil mineral N concentration and texture could be useful for constructing N mineralization prediction models to improve N fertilizer management in agricultural soils. 143 | P a g e 1 2 McGill University, Natural Resource Sciences Trent University, Environmental and Resource Studies Broiler poultry litter (PL) containing C-rich woodchip bedding can induce N immobilization and limit N availability in PL-amended soils. Nitrogen supply in response to five rates (50, 100, 150, 200 or 250 mg total N kg-1 and 0-N control) of PL (C:N ratio = 22) was evaluated using N availability indicators in planted and unplanted soils during a 52-d pot experiment. Soils were amended and pre-incubated for 7 d, then planted with spring wheat (Triticum aestivum ‘Wilkin’), or left unplanted and monitored with Plant Root Simulator™probes containing an anion or cation exchange membrane to adsorb nitrate or ammonium (AEM-NO3 and CEM-NH4), respectively. The N supply from PL was determined by wheat N uptake after 45 d. The N supply pattern was evaluated by N accumulation on exchange membranes every 15 d during the same 45d period. The PL N supply was 40% higher in planted than unplanted soils. Wheat N uptake was related to N availability indicators at planting, namely KCl-NO3, water extractable mineral N, the water extractable C:N ratio (WEC:WEN ratio = 3-8) and AEM-NO3 to 30 d (r = 0.88, 0.85, -0.79, and 0.62 respectively, P < 0.01, n = 20 ). Exchange membranes indicated PL induced N immobilization for 30 d followed by N mineralization between 30 and 45 d. Mineral N concentrations and WEC:WEN ratios (7 d after PL application) were the best indicators of short-term PL N supply. Measuring pre-plant mineral N concentrations could determine the optimal time to plant crops and whether supplementation with mineral N fertilizer is required in PL-amended soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Residual readily mineralizable nitrogen responds differently to manure-type in contrasting soil textures The positive effects of Si on Al and Mn toxicity in sugar and silver maple Peter Tikasz, Benoît Côté Ben Thomas1, Joann Whalen1, Mehdi Sharifi2, Martin Chantigny3 1 McGill University, Natural Resource Sciences Trent University, Environmental and Resource Studies 3 Soils and Crops Research and Development Centre, AAFC 2 Manuring soil alters mineralizable N pools and organic C and N fractions, but the magnitude is manure-type and soil-texture specific, complicating prediction of N mineralization. Our objective was to determine the response of residual soil mineralizable N parameters to manure-type and evaluate their correlation to initial organic C and N fractions, C:N ratios, and mineral N concentrations in sandy loam and silty clay soils following three annual spring applications of manure. Manure types were liquid swine manure (LSM), liquid dairy cattle manure (LCM), or solid poultry litter (SPL), all applied at 90 kg available N ha-1 yr-1. Mineral fertilizer and a zero-N control were also included. Composite soil samples collected (0-20-cm depth) before manure application in the fourth year were incubated aerobically at 25 ˚C for 48 wk. Both soils mineralized N linearly over 48 wk (r2 = 0.96-0.99) and the silty clay soil did not converge to non-linear, firstorder kinetics. Pool I (N mineralized in first 2 wk) was the only mineralizable N pool affected by manure-type, which was depleted by SPL in the sandy loam and increased by LCM in the silty clay. Salt extractable organic N was significantly correlated to Pool I in the sandy loam and silty clay soils (r = 0.52 and 0.74, respectively). Only Pool I was significantly correlated with total N mineralized after 48 wk in the sandy loam and silty clay soils (r = 0.92 and 0.64, respectively). Readily mineralizable N (Pool I) was the most sensitive and robust indicator of mineralizable N after three annual manure applications to agricultural soils from a humid temperate region. Soil texture and manure-type interact to effect residual readily mineralizable N, indicating coefficients of N availability could require adjustment based on soil texture and manure-type. 144 | P a g e McGill University Aluminum (Al) and manganese (Mn) toxicity are common in acidic soils. Al primarily affects the root system and Mn the aboveground portion of plants. Silicates have been shown to alleviate Al and Mn toxicity in various agricultural crops, but only a few studies focused on trees. We hypothesized that maples, which have relatively high leaf Si concentration, could benefit from such protection. Seeds of sugar maple (Acer saccharum Marsh.) and silver maple (Acer saccharinum L.) were germinated and transferred to hydroponic systems. Fifteen different nutrient solutions with and without Si (0 or 2000 µM), different Ca/Al ratios (5.0, 1.0, 0.5 and 0.25), Mn concentrations (0 or 728 µM) and Al concentrations (100, 500, 1000 and 2000 µM) were tested. All solutions were maintained at pH 4.5 for the duration of the study. Seedlings were harvested after 21 days and several physical characteristics were measured: root and shoot length and dry weight, root surface area and shoot:root dry weight ratio. Sugar maple’s responses to increasing levels of Al with or without Si were small; the shoot:root ratio decreased by 38% (p < 0.0001) at the highest Al concentration and root diameter decreased by 33% (p < 0.0001) with the addition of Si. Silver maple seedlings experienced a more detrimental effect of high Al concentration without Si. Root dry weight and root length were on average 6mg heavier (p < 0.0003) and 18mm longer (p < 0.0001) with Si. True Mn toxicity was not achieved in our experiment but both species responded positively to the addition of Si. The stem length of sugar maple increased by 23% (p < 0.0032) and the shoot:root ratio of silver maple increased by 18% (p < 0.0020) with Si. Overall, the effects of Si were mainly morphological and more pronounced for Al in silver maple and for Mn in sugar maple. Further studies are required to determine if similar effects can be induced in the field. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Nitrogen cycling from legume and grass forages during forage phase and subsequent potato phase Jennifer Whittaker1, Judith Nyiraneza1, David Burton2, Bernie Zebarth3, Vernon Rodd1, Yefang Jiang1, Mark Grimmett1 1 Crops and Livestock Research Centre, AAFC Department of Environmental Sciences 3 Potato Research Centre, AAFC 2 There is increased attention on potato production in PEI and the environmental and health concerns of excess nitrogen (N) as NO3- entering the groundwater. The economic importance of potatoes in PEI, necessitates a better understanding of N cycling in potato rotations. A rotation experiment was established in spring 2013 at Harrington Research Station, PEI to assess how nitrogen is cycled from forages in soil and soil solution before and during potato phase. Barley was underseeded with red clover alone (RC), timothy alone (T) or a timothy-red clover mixture (M). Forages were left to regrow in 2014. Ceramic suction (30 and 50 cm) and steel lysimeters (zero-tension, 80 cm) were installed belowground in 2013 and 2014 respectively to estimate soil solution NO3-. Between May-October 2014, anion exchange membranes (AEM) were buried (15 cm) and replaced every two weeks to measure released soil NO3-. In June 2014, the first cut forage dry matter was comparable among RC (4.55 Mg ha -1) and M (4.72 Mg ha-1) but significantly lower in T (1.42 Mg ha-1). Similar trends were observed for dry matter in August and October before ploughdown and for corresponding total N accumulation. Nitrogen release from the root zone as measured by AEMs was 11.54, 89.32, 101.19 NO3- μg 10 cm-2 2 weeks-1 for T, M, and RC respectively at peak N release (September). The C:N ratio at ploughdown was T > M > RC. The concentration of NO3- was highest in RC for both lysimeters though observed values were considerably higher in steel lysimeters. Preliminary results from lysimeters and AEMs indicate their ability to assess different forage treatments and potentially estimate N availability or loss. Potatoes will be planted in 2015 and yield, total N uptake and NO3- in soil and soil solution will be determined following potato harvest. 145 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S2: Dynamics of Pollutants in Soil 146 | P a g e Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Estimation of Volumetric Oil Content with Thermo-Time Domain Reflectometry Techniques Impacts of Competitive Sorption Processes on Pb Bioavailability in Urban Soils Jennifer Bower, Nicolas Perdrial Shinsuke Aoki, Hidetoshi Arikawa, Kosuke Noborio, Meiji University, Agriculture Subsurface and groundwater contamination with organic compounds by accidents and/or activities at gas stations, and various industrial facilities may result in a serious environmental problem. The remediation of contaminated soil sites requires the information on how large volumes of soil and groundwater are contaminated. Methods commonly used to characterize contaminated sites may be coring soil and sampling water. Those methods are labor intensive so that detecting contamination is apt to be delayed. For the early detection of soil contamination, simple monitoring techniques have been desired. Objectives of our research were to develop a procedure to estimate mineral-oil content in unsaturated soil with a thermo-time domain reflectometry (thermo-TDR) probe. As a thermo-TDR probe combines a heat pulse technique with a TDR technique, it is possible to measure the volumetric heat capacity and dielectric constant of soil, respectively. We thought that those techniques enabled us to detect oil in soil because volumetric heat capacity and dielectric constant for mineral oil are dissimilar to those for other constituents of unsaturated soil. We used a three-wire thermo-TDR probe (0.040 m long, 0.0075 m spacing, the center rod housing a nichrome heater wire, and the outer two rods containing type-T thermocouples) to measure the soil properties of volcanic ash soil and glass beads (0.037 ~ 0.063 mm) contaminated with kerosene. The porous materials were mixed with the combinations of volumetric ratios of kerosene and distilled water. A series of experiments were conducted to develop relationships among volumetric oil content, volumetric heat capacity, and dielectric constant. Using those relationships established, volumetric oil content in the unsaturated porous materials were estimated. Estimation of volumetric oil content in glass beads was better than that of volcanic ash soil. 147 | P a g e University of Vermont, Geology The presence of contaminant metals in soils is a worldwide and widespread issue of concern, but in-situ remediation efforts are often hindered by the complexity and heterogeneity of soil systems. Through multiscale analysis of column experiments, this project aims to model competitive sorption dynamics, using Pb as an element of concern, with the goal of constructing a quantitative, predictive tool for soil competitive sorption to be applied toward soil remediation. Representative soil samples containing as much as 12,000 mg kg-1 Pb were sourced from a Burlington, VT site contaminated with legacy Pb from exterior paint. A series of column experiments is then conducted, testing the mobility of Pb as a function of the pH of rainwater, before beginning column experiments investigating multiscale expressions of competitive processes influencing Pb speciation and bioavailability. Next, amendments of goethite (FeO[OH]) and PO4 in specific ratios are added to soil columns and leached with synthesized rainwater in order to examine the speciation and bioavailability of Pb using molecular, micro- and macro-scale tools (XAS, XRD, SEM, XRF and elemental analysis). Coupling the experimental evaluation of Pb bioavailability as a function of the presence of competitive sorbents with numerical prediction of sorption behavior using the reactive transport model CRUNCHFLOW will contribute to the development of a quantitative, predictive tool relevant to the remediation of Pb-affected systems. Eventually, the goal of this research is to help generate sustainable Pb remediation techniques that are effective in a diversity of soil types. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Polycyclic aromatic hydrocarbons (PAHs) in sewage sludge compost in context of soil fertility J. Bien, E. Neczaj, M. Milczarek, D. Wloka, A. Grosser, M. Worwag Czestochowa University of Technology, Institute of Environmental Engineering Bioaccessible Nickel in Various Particle Sizes of House Dust from Communities Close to Nickel Mining and Smelting Operations Nancy Dai1, Luba Vasiluk1, Beverley Hale1, Mike Dutton2 1 2 The sewage sludge compost is rich in organic matter and mineral nutrients, such as nitrogen, phosphorus and potassium hence it can be recycled as organic fertilizer to improve soil fertility. However, toxic pollutants are also enriched in sludge during the wastewater treatment. One of the most abundant organic pollutants are polycyclic aromatic hydrocarbons (PAHs). The presence of toxic pollutants in sludge poses some risk to the environment and human health. Therefore, it is necessary to minimize or remove these contaminants before land application of sewage sludge. Composting, a cost-effective method for sewage sludge disposal, is able to suppress pathogenic organisms, reduce the bioavailability of heavy metals, and stabilize organic matters. Composting has been also proven effective for the degradation of PAHs with high removal rates. In this study the changes in the concentrations of 16 polycyclic aromatic hydrocarbons identified by the EPA as priority pollutants were investigated during the composting process of sewage sludge mixed with organic fraction of municipal solid waste, green waste and bulking agent. Composting appeared to be an effective method for the removal of PAHs in sewage sludge. After 30 days of composting, a significant reduction of concentration of the total PAHs was detected as compared with the initial concentration in composting material. The significant relationship between the biodegradation of organic matter and the losses of Σ 16 PAHs during composting indicated that microbial degradation was the key process responsible for the efficient removal of PAHs from the sludge. It was found that it is possible to achieve organic pollutants decomposition and improve the compost properties parameters with the optimal composition of different wastes mixtures so is possible to use that compost in agriculture. 148 University of Guelph Vale Canada Ltd. Nickel accumulation after ingestion of elevated nickel levels from soil and dust may be a significant source of exposure for communities close to nickel mining, smelting, and refining operations. Indoor dust particles that settle on surfaces adhere upon contact to the hands of children and adults, who then ingest it through hand-to-mouth behaviors. This needs to be considered as a separate exposure pathway from soil ingestion, due to higher organic carbon content in dust and its higher total and bioaccessible nickel concentrations. Bioaccessible nickel, the amount of nickel that becomes available for intestinal absorption as a result of digestion in the stomach, is likely a more accurate exposure measure compared to total nickel concentration present in house dust. Prior work at uncontaminated sites shows that smaller dust particles may have higher total nickel concentrations than bulk particles do. For bioaccessible nickel, finer particles can have increased or decreased nickel depending on the site of origin. We are examining the relationship between particle size and nickel bioaccessibility in Port Colborne and Sudbury house dusts. Samples are being separated using plastic sieves into ranges of <10 µm, 10-41 µm, 41-70 µm, 70-105 µm, 105-150 µm, and 150-250 µm. Nickel bioaccessibility is being determined using in vitro SBRC glycine digestion, which simulates stomach pH and churning. Samples will be analyzed using Flame Atomic Absorption Spectrometer. We hypothesize that there is a relationship between particle size and nickel bioaccessibility in house dust, but do not know whether to anticipate that nickel bioaccessibility will be higher or lower in fine particles compared to coarse particles. Study results will inform risk assessors on the contribution of indoor dust to total nickel exposure through ingestion, for populations close to nickel mining and smelting activities. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Toxicity of silver nanoparticles in biosolidamended soil to the earthworm Eisenia fetida Monica Gonzalez Linares, Joann Whalen, Geoffrey Sunahara McGill University, Natural Resource Sciences The impact of a one-fold application of sewage sludge on the parameters of trace metals contaminated soil Anna Grobelak1, A. Placek1, M. Kacprzak1, B. R. Singh2, Ǻ. Almas2 1 Silver nanoparticles have many uses in everyday life, particularly due to their antibacterial properties. As a consequence of their use in domestic products, medicine and industry, silver nanoparticles will end up in waste water treatment plants. Biosolids remaining after secondary or tertiary water treatment are enriched in silver nanoparticles and thus, may pose a risk to the health of soil ecosystems when they are disposed through land application. The aim of this project is to determine if silver nanoparticles are toxic to the earthworm Eisenia fetida, using survival and reproduction toxicity tests following exposure to biosolid-amended soil containing this potential contaminant. Controlled laboratory experiments were conducted with natural soil (Delacour soil series) and artificial soil (OECD soil) that received biosolids spiked with silver nanoparticles at 4, 40, 200, 400, and 800 ppm. Adult earthworm survival was evaluated after 14 days, as well as cocoon production and hatching after 42 days. Bioaccumulation of nanosilver in earthworm tissues was measured. Earthworm mortality is expected when exposed to biosolid-amended soils containing more than 400 ppm of silver nanoparticles, and reproduction is expected to be more sensitive to exposure to silver nanoparticles. Biosolids in waste water treatment plants could be enriched with as much as 195 ppm of silver, and the quantities applied through land application of 5 ton biosolids ha-1 would be less than 1 ppm. Although silver has relatively low mobility in soil, biosolids could be a preferred food source for earthworms and thus nanosilver could be bioaccumulated and transmitted through the soil foodweb, but this needs to be determined. 149 Czestochowa University of Technology, Environmental Engineering 2 Norwegian University of Life Sciences, Environmental Sciences The main objective of the study was to obtain the physical and chemical soil parameters improvement and to investigate the effect of a onefold sewage sludge amendment on the soil reclamation and metals mobility after five years of conducting the phytostabilisation process. The field experiment was conducted in the contaminated area near zinc smelter, in soil with high heavy metals concentration (Cd, Zn, Pb), and generally low pH, nutrients, carbon and CEC. The process of phytoremediation was initiated with the onefold application of sewage sludge and with the use of Scots pine (Pinus sylvestris L.). One time application of sewage sludge increased the soil CEC compared to untreated soil and this effect was more pronounced on plots with trees. This same effect was also observed for nitrogen and phosphorus. For control plots with sewage sludge, the slight decrease of pH was noted compared to untreated plots, and moreover there was an opposite result for plots with plants, where for amended plots the pH value was higher. The content of total carbon was also much higher in plots with sewage sludge application. It was found that on fertilised plots the concentration of heavy metals was similar to those values found at the beginning of the experiment. Moreover, on plots without sewage sludge amendment, the values decreased. This indicates, that metal were released into the deeper soils layer or groundwater. The research of bioavailable fractions of metals also confirmed that application of sewage sludge resulted in the phytostabilisation process of metals, preventing the metal leaching. Results confirmed that the effect of onefold use of sewage sludge was beneficial for soil parameters and reclamation process for at least five years. Sewge sludge is a valuable source of biogenic elements, and its onefold addition has long lasting effect. Results proved the need to support the phytostabilisation processes conducted on contaminated soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The bioaccumulation of heavy metals in trees organisms during long-term field experiment on polluted soil this species were poor. Moreover a significant amount of heavy metals were accumulated in the leaves of oak and were then penetrated into the soil environment as a result of recontamination. A. Placek1, A. Grobelak1, M. Kacprzak1 *, Bal Ram Singh, Asgeir Almas2 1 Czestochowa University of Technology Norwegian University of Life Sciences, Department of Environmental Sciences 2 The objective of the research was to indicate the extent of translocation and accumulation of heavy metals in trees biomass during phytoremediation of degraded soils carried out in the field conditions. The five-year study was focused on the migration of Cd, Zn and Pb ions into the roots of plants followed by their translocation and bioaccumulation in the aerial parts of trees species: Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L.) and oak (Quercus robur L.). The degree of accumulation of trace elements in different parts of the plants was determined on the basis of: the translocation factor, bioaccumulation factor and metal extraction ratio. The field experiment was carried out at a near distance of the zinc smelter. The soil on degraded area is classified as poor in nutrients, is distinguished by a low pH and sorption capacity, and is characterized by high accumulation of heavy metals (mainly in the top level). In order to perform the planned field trials experiments, two research plots were formed. On the first plot the sewage sludge from the food industry was applied. In contrast, the second plot was used as a control for the first plot, without the sewage sludge application. For both research plots the three species of plants were planted. On the plot fertilized with sewage sludge, the proper growth of plants and large increase in biomass of trees were noted. Hence sewage sludge used in this experiment has considerable importance not only as a source of organic matter, but also in the phytoremediation process of soils contaminated with heavy metals (Cd, Zn and Pb). The conducted field experiment demonstrated that selected trees like Scots pine and Norway spruce, because of its excellent adaptability, can be used in the remediation of soil and of soilless devastated areas, such as pioneering plants. These two species of plants collected and accumulated large amounts of heavy metals mainly in their shoots, so can be used even in the phytoextraction process in relatively long time. Oaks should not be used in the phytoremediation process of soils contaminated with high concentrations of trace elements in the soil, because the tolerance of 150 The impact of organic additives on the content of PAHs in soil Anna Grobelak1, D. Wloka1, A. Placek1, A. Napora1, M. Kacprzak1, B. R. Singh2, Ǻ. Almas2 1 Czestochowa University of Technology, Environmental Engineering 2 Norwegian University of Life Sciences, Environmental Sciences The aim of the experiment was to determine the impact of sewage sludge and compost on soil contamination with PAHs (polycyclic aromatic hydrocarbons). The sewage sludge and the compost obtained from sewage sludge composting process were tested for their suitability as fertilizer material. The compost was obtained from the composting of sewage sludge and green biomass of grass. The pot experiment was carried out under controlled conditions of phytotron chamber for three months. Soil material used in the study was collected from post-mining land lignite mine dump in Belchatow (Poland) and was contamined with PAHs. In this experiment the organic amendments were mixed with the soil at reclamation doses. The organic amendments contained significant amounts of PAHs and moreover, the used sewage sludge contained higher concentrations of PAHs compared to compost. The application of sewage sludge into the soil, in the first stages of the process contributes the increasing concentrations of such contaminants, but after the incubation period, organic additives resulted in an increased efficiency of biodegradation of contaminants compared to control soil without amendments. A similar situation also concerned the application of used compost, however, the bidegradactio efficiency was much higher. During the remediation process of degraded soil conducted with organic amendments the improvement of many soil parameters was obtained. The application of sewage sludge and compost is associated with a short-term increase in the concentration of PAHs in the soil which in the long term, however, is mitigated in increased efficiency of biodegradation of soil contaminants. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Rendement de zones tampons végétales aménagées pour atténuer la contamination des eaux de surface par le glyphosate et l’AMPA en champs agricoles Small-scale horizontal variability of glyphosate and AMPA concentrations in top soil along three transects across two cultivated fields and their riparian buffer strips Pierre Lafrance1, Marie-Josée Simard2, Geneviève Bégin3, Georges Thériault3, Eric van Bochove4 Université INRS – Centre Eau, Terre et Environnement (ETE) 2 AAC Centre de recherche et de développement en horticulture 3 AAC Centre de recherche et de développement sur les sols et les grandes cultures 4 AAC Direction générale, recherche et transfert de technologie Pierre Lafrance1, Marie-Josée Simard2, Geneviève Bégin3, Georges Thériault3, Eric van Bochove4 1 La présence de pesticides dans les eaux de surface des bassins versants agricoles est fréquemment observée au Canada. Les Pratiques de Gestion Bénéfiques (PGB) en agriculture incluent l’utilisation de zones tampons végétales qui permettent d’atténuer l’exportation des pesticides par ruissellement de surface. Deux principaux types de zones tampons sont utilisés : (1) bandes riveraines enherbées (BRE) et (2) voies d’eau engazonnées (VEE). Le but de cette étude est de quantifier, à l’échelle du champ agricole (maïs et soya), l’efficacité de ces deux zones tampons à atténuer les pertes de glyphosate et d’AMPA (produit de dégradation). Cette étude fait partie du projet EPBH mené par Agriculture Canada (2004-2012). Le site d’étude est une section d’un micro-bassin versant (2,4 km2) du bassin de la rivière du Bras d’Henri près de la ville de Québec. La BRE (5 à 7 m de largeur) a été échantillonnée au coin (BC) et vers le centre (B). La VEE (18 m de largeur) a été échantillonnée au centre (VEC). Le glyphosate a été appliqué à un taux voisin de 1 kg i.a./ha. L’eau a été prélevée en 2011 DURANT les trois premières pluies survenues suite à l’application du glyphosate. Les résultats démontrent que les concentrations en glyphosate et en AMPA dans l’eau ruisselée décroissent rapidement après chaque pluie. La réduction des composés herbicides a été très élevée pour le site BC (66% à 100%), faible pour B (7% à 31%) et modérée à élevée pour VEC (30% à 90%). La faible efficacité de B a été attribuée à une infiltration d’eau et un possible écoulement latéral de subsurface sous la zone racinaire. La concentration en glyphosate dans l’eau des fossés de drainage a été très faible. Ces deux types de zones tampons ont montré, dans les présentes conditions, une bonne efficacité de protection des eaux. 151 Université INRS – Centre Eau, Terre et Environnement (ETE) 2 AAC Centre de recherche et de développement en horticulture 3 AAC Centre de recherche et de développement sur les sols et les grandes cultures 4 AAC Direction générale, recherche et transfert de technologie 1 Riparian buffer strips (RBS) are structures that aim to limit the losses of agricultural contaminants by runoff toward surface waters. Few studies have addressed the residual concentrations of pesticides, especially glyphosate, in the surficial soil in both cultivated fields and their adjacent RBS. A better understanding of the behavior of pesticides in soils of fields and RBS, is fundamental to improve RBS management and efficiency. The objective of this study was to quantify late summer herbicide concentrations in soils of fields sprayed with glyphosate, and adjacent RBS, located near Quebec, Canada. In 2012, glyphosate and AMPA (its primary metabolite) concentrations were measured in soil samples (5 cm depth) taken from 0 (edge of RBS and ditch) to 60 m into the fields along 3 horizontal transects in 2 soybean fields 1 month after repetitive glyphosate applications (4 June and 3 July). Five samples were collected both in the RBS and in the fields. Only one rain event (26-27 June, > 50 mm) generating runoff through the RBS occurred, 36 days before sampling. Results demonstrate that concentrations do not vary with distance from the edge of the field, in the field, or distance from the ditch, in the RBS. However, for 2 out of 3 transects glyphosate concentrations were 7 (field 1, RBS 1) to 30 (field 1, RBS 2) times lower in the RBS than in the field. AMPA values showed similar trends but differences were weaker and not significant. The ratio of AMPA/glyphosate concentrations was evaluated as a possible indicator of glyphosate degradation in soil. As expected by the observed differences in glyphosate and AMPA values, ratios were higher in RBS (mean: 8.14) than in fields (mean: 2.50). The dynamics of the compounds in soil suggest that the degradation of glyphosate in buffer strips remains higher than in the fields. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Determining detection limits for uptake of metals in mixtures from soils using PRSTM and DGT probes Amanda Laird1, Siciliano2, Steven Hale1 Arsenic dynamics in paddy rice fields in temperate climate Maria Martin1, Daniel Said Pullicino1, Luisella Celi1, Elena Zanzo1, Marco Romani2, Lucia Cavalca3, Marcella Sodano1, Daniele Tenni2, Eleonora Miniotti2, Elisabetta Barberis1 Beverley 1 University of Guelph University of Saskatchewan 2 1 Università di Torino, DISAFA Ente Nazionale Risi 3 Università di Milano, DeFENS 2 Metal contamination in soils often occurs as mixtures of more than one metal. Although there have been numerous studies on how single metals are taken up by plants from soil, the accumulation and toxicity of metal mixtures remains largely unstudied. Furthermore, tools for risk assessment of mixtures of metals in soils are lacking. One possible addition to the toolkit is the use of ion exchange resins as proxies for plant root accumulation of metals from soil. Plant root simulator (PRSTM) probes have their origins in testing for soil nutrient bioavailability, but have been applied to use in metal bioavailability. Diffusive gradients in thin film (DGT) were originally created for measuring bioavailability of metals in water, but were also adapted for use in soil. The application of these methods to metals in soil is not yet universal, and the implications of the multiple metals for these tools remain unknown. These tools show promise for applications in risk assessment in situations with metals in mixtures. In order to evaluate the usefulness of these tools for risk assessment of metals in mixtures, we must first determine if the probes are as sensitive as plants are in detecting the presence of metals at elevated concentrations, especially when there is more than one metal of concern. To this end, the detection limits of PRSTM and DGT probes are being determined. The probes are deployed into soils with a known range of metals in combination (Ni, Cu and Co), including field soils collected from around Ni mining and smelting activities. The uptake of these metals by the resin devices will be compared to the total and bioaccessible metal concentrations in the soil. From this study, we will determine detection limits for PRSTM and DGT relative to total and bioaccessible soil metals. 152 The reason why rice can become a source of arsenic (As) in human diet lies with the enhanced As phytoavailability during the prolonged soil submersion, and the microbially mediated changes in the redox equilibria involving Fe and/or As species. The microbial activity, in turn, depends on, and contributes to determining the quality and quantity of available organic matter and hence, drives the organo-mineral interactions occurring under alternating redox conditions. Water management practices that involve different durations and intensities of field flooding may strongly influence As dynamics in paddies and consequently As content in rice as well as the composition and activity of the microbial communities. Under continuous flooding, As concentration in solution increased drastically after the first three-four weeks and then tended to stabilize or even decrease in the second part of the cropping season, similarly to other redox-sensitive analytes, such as Fe and Mn. Flooding also resulted in an increase in the concentrations of dissolved organic carbon coupled with a gradual increase in the aromatic character during the cropping season. During soil flooding, rhizospheric microbial populations involved in As cycling are markedly selected with a concomitant increase in Fe-reducing bacteria. Conversely, in soils under aerobic conditions soil solution As concentrations were negligible and those of Fe, Mn and organic carbon remained much lower. Although aerobically cultivated rice showed a much lower As content in grain, the yields decreased markedly. In the flooded systems, the introduction of a relatively short drying period before rice flowering was effective in keeping As concentrations in soil solution low, limiting contents in the rice grain without compromising the yield. The effect of this strategy on As biogeochemical cycling is still under evaluation. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Iron and arsenic co-precipitates: complex interfaces Maria Martin1, Roberta Gorra1, Elena Zanzo1, Laura Calotescu1, Antonio Violante2, Salvatore Deiana3, Elisabetta Barberis1 Remediation of salt and chlorinated organic contaminated fine textured soils and ground water Alison Murata, M. Anne Naeth University of Alberta, Renewable Resources 1 University of Torino, DISAFA 2 Università di Napoli “Federico II” 3 Università di Sassari, Agriculture The transformations affecting As mobility at the redox interface are mainly mediated by microorganisms involved in the redox cycling of Fe, Mn, and As. The dynamics of these populations, often forming biofilms, depend on the chemicophysic environment, and are still poorly understood. The study of natural systems may be challenging and may provide site-specific results. Synthetic simplified models, conversely, might overlook the effects of some components of complex systems, such as organo-mineral phases at the solidliquid interface. Combining both approaches could improve the interpretation of complex phenomena. The As release from co-precipitates naturally formed in Bangladesh was compared with that from synthetic FeAs precipitates. Iron oxy(hydr)oxides were the main component of all materials, but the natural ones also contained carbonates, phosphates and microbial organic matter. The As release varied with the composition, concentration and pH of the solution. Both synthetic and natural co-precipitates released less than 2% of the total As content with diluted organic and inorganic P-extractants while, at higher concentration the natural co-precipitate released much more As than the synthetic ones. The oxidation of the organic matter in the natural co-precipitates significantly affected As extractability. Kinetics of As release from synthetic FeAs-polygalacturonate precipitates evidenced the hindrance of the organic coverage. Organic interface can be determinant in regulating As mobility at the solid-liquid interface. 153 Soil and ground water are commonly contaminated by industrial activities. The contamination poses a risk to human and environmental health and prevents productive land use. Contaminant mixtures make remediation complex due to the differing behaviors of various compounds. The University of Alberta’s Ellerslie Waste Management Facility was used to process laboratory waste from 1972 to 2007 and is contaminated with salts and chlorinated organic compounds. This research is focused on characterization and remediation of the site. Ground water has been monitored for over 26 years providing an extensive data set. Analytical parameters include pH, electrical conductivity, major ions, volatile organic compounds and metals. The data are being analyzed to determine trends indicating contaminant movement or degradation. A laboratory scale experiment is being carried out to examine the potential of indigenous soil microorganisms to anaerobically biodegrade trichloromethane, one of the most common chlorinated organic contaminants on site. Treatments are acetate, canola oil, nitrate and sulfate. The acetate and canola oil serve as carbon sources to support reductive dechlorination. The nitrate and sulfate provide terminal electron acceptors for different redox conditions. Preliminary results indicate that salt and chlorinated organic contamination is spatially concentrated in and down gradient of a former waste water pond which is known to have leaked in the early 1980s. Microorganisms from the site are active and may be able to biodegrade trichloromethane. Results from this research will be essential to managing and remediating the site so that the land can be returned to the Crown and safely used for other purposes. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Application of different bio-wastes as a fertilizers for degraded soil - a review Using XAFS synchrotron radiation and CISED sequential extraction to identify the effect of speciation and mineral association of nickel on bioaccessibility in soil Ewa Neczaj, K. Fijalkowski, A. Grosser, M. Worwag Czestochowa University of Technology, Environmental Engineering Ryan Thorn1, Beverley Hale1, Mike Dutton2 1 University of Guelph Vale Base Metals 2 Due to increasing human consumption, a large amount of organic wastes are generated. The use of organic amendments, such as biosolid, compost, sewage sludge, and municipal solid wastes are used as a source of nutrients and also as a conditioner to improve the physical properties and fertility of different kind of soils. However it must be taken into consideration that greater public awareness of the implications of different kind organic amendments into the soils have a influence on human and ecosystem health, so understandable is increasing interest amongst the scientific community and regulatory agencies in the development of technologies to remediate contaminated sites. Organic wastes have been utilized as beneficial soil amendments for a long time. Animal manures have in the past been widely used as a source of essential nutrients to soils. The more recent concern about soil fertilization due to the lack of phosphorus depletion has resulted in biowastes being used as materials for remediation. In addition, the increase in wastewater generation and intensification of human living has resulted in large quantities of solid organic wastes from very widely different sources with variable composition. Several industries generate significant quantities of organic waste, such as paper mill factories, olive mills, wastewater treatment plants etc. There have been increasing interests in examining the value of organic amendments such as biosolids, manure composts, and biochars in both enhancing C sequestration and improving soil quality in terms of physical, chemical, and biological fertility. The addition of biosolids to the degraded soil improved the soil physical, chemical, and biological properties, thereby increasing the plant growth and biomass. Biosolid addition also increased C sequestration in soils through directly supplying organic C to soil and indirectly enhancing root biomass. 154 Risk assessments carried out on contaminated sites in Canada and many other jurisdictions around the world currently use generic bioaccessibility estimates, which are likely to over-estimate contaminant exposure to human and ecological receptors. This can lead to inflated risk estimates and unnecessary, costly remediation of sites. The current study characterizes the speciation and mineral associations of Ni in soil particles to give a clearer picture of the mechanisms which influence the bioaccessible fraction of total [Ni], and hence, exposure estimates. The influence of aging on Ni bioaccessibility in soil was investigated using packed silt loam soil columns spiked with 3000 mg kg-1 NiSO4•6H2O, and subjected to varying leaching rates. Organic matter amendments investigated the complexation of Ni with organic matter. An aging period of 168 days was used, and soil, pore water, and leachate samples collected at intervals throughout. Nickel K-edge X-ray absorption near-edge structure (XANES) spectroscopy analysis allows species to be identified in their natural state, which generates more reliable data than sequential extraction methods. XANES was employed for species identification and mineral interactions. A sequential extraction technique, Chemometric Identification of Substrates and Element Distribution (CISED), was used in conjunction with XANES to compare the synchrotron method to a more traditional technique. In addition, pore water and leachate were analyzed for total [Ni] to understand mobility of the Ni relative to speciation, within the column depth. The majority of Ni in the columns had, in fact, gradually converted from NiSO4•6H2O to less soluble species (i.e. NiO, NiOH, and NiFe2O4). Soluble Ni decreased from 71.5% after spiking, to 37.6% over the 168 day period, while insoluble Ni increased from 28.5% to 62.5% over the same period. This study highlights the importance of speciation, and therefore bioaccessibility, to the estimation of exposure and risk in contaminated site risk assessment. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Kinetic speciation of metal nanoparticles in presence of biosolids Elena Vialykh1, Cooper H. Langford1, Gopal Achari2 1 University of Calgary, Chemistry University of Calgary, Engineering 2 Production of nanomaterials increases rapidly nowadays as a result of the amount of used nanomaterials also found in increasing waste. One of the areas which is affected by presence of metals nanoparticles (NP) is water wastes. Removal of NP from waste water during treatment process is related to the last step water treatment process, in particular to biological treatment. Thus there is a high content of NP accumulates in activated sludge and consequently in biosolids. Since there is common application of biosolids as fertilizer on agricultural fields, the NP can migrate from biosolids to draining water, as well as to the soil, and further to plans which are cultivated there. It’s known that some metal NP can be very stable at different conditions, whereas another can undergo chemical destruction and transformation easily. In this work kinetic behavior of zinc oxide NP in presence of biosolids was studied. Chelex ion exchange resin was chosen as a ligand with higher affinity to ZnO NP compare to biosolids. Biosolids were spiked with different ZnO NP amount, left for 24 hour to equilibrate and then mixed with Chelex resin to evaluate the rate of ZnO NP release from biosolids. The results showed that ZnO nanoparticles were bound to biosolids weakly because a major part of ZnO NP became adsorbed by Chelex resin. However there was a small percent of ZnO NP which was not recovered from biosolids. Thus we can conclude that ZnO NP are labile in biosolids mainly and can easily move to water or be adsorbed by stronger ligands. However the small portion of NP remains bound to biosolids and consequently NP can be accumulated in soil with time if regular adding of new portions of biosolids will occur. 155 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S3: Soil Microbiology 156 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Root nodulation of lentil is enhanced by select phytohormone producing and H2oxidizing bacteria Effect of Plant Growth Promoting Rhizobacteria on Hyphal Growth of Arbuscular Mycorrhizal Fungi in Axenic Culture Lobna Abdellatif, Chantal Hamel, Keith Hanson, Yantai Gan Lobna Abdellatif1, Chantal Hamel1, Takaaki Ishii2, Keith Hanson1 AAFC, Saskatchewan 1 Ten H2-oxidizing bacteria isolated from lentil growing in semiarid Saskatchewan, of the genera Paradoxus, Rhodococcus, Mycobacterium, Acinetobacter and Curtobacterium were tested and screened for several plant-growth-promoting traits. Siderophore production was expressed by almost all the bacterial isolates. Only one bacteria was positive for phosphate solubilization. Indole acetic acid (IAA) production was found in four bacterial isolates and 1-aminocyclopropane-1carboxylate (ACC) deaminase in six bacterial isolates. Dual inoculation of lentil with Rhizobium sp. plus individual H2-oxidizing rhizobacterial isolate could greatly enhance root nodulation. We conclude that several H2-oxidizing bacterial isolates members of the genera Paradoxus, Mycobacterium and Curtobacterium, which have plant-growth promotion, may have potential for development as biofertilizer for legume crops in Canada. 157 AAFC, Saskatchewan Kyoto Prefectural University 2 Arbuscular mycorrhizal fungi are ecologically important for the growth and survival of most vascular plants. The (AM) fungi are obligate biotrophs; however their spores can germinate in the absence of host plants. In recent years, there have been many studies showing the external mycelia of symbiotic fungi are colonized by group of bacteria known as Mycorrhization Helper Bacteria (MHB), which influence the growth of external fungal mycelia and mycorrhizal root colonization. We used the IH base medium, a new medium to grow the commercial arbuscular mycorrhizal fungus Rhizophagus irregularis in absence of a host plant. We tested also the influence of plant growth promoting rhizobacteria (PGPR) of the genus Variovorax and Mycobacterium on the (AM) fungus Rhizophagus irregularis. Axenic spores of R. irregularis from in-vitro culture were placed in Petri dishes containing or not one of three of PGPR. The petri dishes were incubated in an inverted position in the dark, at 21°C, and regularly observed under the microscope. R. irregularis in axenic cultures showed the ability of AM fungi to growth and develop of extraradical mycelial network and anastomoses between germ tubes. We observe differences in extra fine elongations between terminal mycelia and anastomosis frequency between different mycelia. In the presence of Variovorax, R. irregularis produced significantly larger mycelia than the axenic control. After 3 weeks, the formation of new spores was only observed in Petri dishes containing Variovorax sp. strain L1 and after 4 weeks, with the Variovorax sp. strain L17. Mycobacterium sp. strain L11, did not show MHB properties and, it did not influence the growth of the AM fungus. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Shifts in soil bacterial functional gene composition in response to willow planting and contamination level Methane oxidation dynamics and methanotroph community structures in peatlands across a sulphur and metal deposition gradient in Sudbury, Ontario Fahad Alotaibi1, Terrence Bell1, Saad El-Din Hassan2, Etienne Yergeau3, Mohamed Hijri4, Marc St-Arnaud4 Gurpreet Aulakh1, Michael A. Carson1, Galen Guo1, Graeme Spiers2, Nathan Basiliko1 1 1 2 2 Université de Montréal, Soil Science Al-Azhar University, Botany and Microbiology 3 National Research Council Canada, Energy, Mining and Environment 4 Université de Montréal, Biodiversity Centre Plant-associated bacteria are important for the growth and health of their host, but little is known about the functional diversity of these bacteria, particularly in the context of phytoremediation. We studied bacterial functional diversity in the rhizosphere of willows (Salix spp.) growing in petroleum-hydrocarbon contaminated soils, as well as in non-contaminated soils. Our hypothesis was that functional gene composition would vary based on plant identity and contaminant level, as was observed previously when looking at the taxonomic composition of the microbial communities (bacterial 16S rRNA and fungal ITS). In this study, we used high-throughput 454 pyrosequencing of two key functional genes related to petroleum hydrocarbon biodegradation, namely biphenyl dioxygenase (BphA) and alkane monoxygenase (alkB), as well as nitrogen fixation genes (nifH), which play a key role in determining the amount of nitrogen available to both microorganisms and plants. Preliminary analysis of our sequence data suggests that distinct bacterial populations of petroleum-hydrocarbon degrading bacteria and N-fixers where present across willow rhizospheres and bulk soil. This project is part of GenoRem, a collaborative initiative that is funded primarily by Genome Canada that aims to gain an integrated understanding of the relationships between fungi, bacteria, plants, and soil to enable the design of treatments that promote effective bioremediating communities. 158 Laurentian University, Biology Laurentian University, Environment Methanotrophic bacteria are ubiquitous microorganisms that aerobically oxidize methane (CH4) as their sole carbon and energy source. Atmospheric CH4 is a potent greenhouse gas produced by a strictly anaerobic group of Archaea known as methanogens. Oxidation of biogenic CH4 emissions from in wetland soils by methanotrophs plays a critical role in the carbon cycle by reducing the overall release of CH4 to the atmosphere. It is known that environmental copper (Cu) influences expression of different CH4 monooxygenases, the enzymes which initiate CH4 oxidation, and that sulphate (SO4) inhibits methanogens, altering CH4 efflux. Consequently, it is believed that both factors modulate methanotrophic community structures and activity. In this study we examined the impact of prolonged metal and sulphur loading from local smelting activities on methanotrophs across ten poor to intermediate fen peatlands in Sudbury, Ontario, Canada. We predicted that methanotroph diversity and activity would be most severely altered in high deposition sites near smelters. Concentrations of bioavailable inorganic elements (Cu, Ni, Fe, Ca, S, N) were analyzed in surface peat soils and porewater samples. To assay methanotroph activity, potential rates of methane oxidation were quantified in soil incubations. Abundance of the CH 4 monooxygenase genes (pmoA and mmoX) were determined by quantitative PCR and the methanotrophic community was characterized using TRFLP and 454 pyrosequencing of the pmoA gene. Methane oxidation rates were variable across sites, and there was no clear correlation with distance from smelters (r = 0.1892, p > 0.05). Preliminary analysis of methanotroph diversity indicates a change in community structures in fens most proximal to smelters. Initial results suggest that prolonged chemical deposition has altered methanotroph communities while not affecting rates of CH4 oxidation, however further analyses with chemical data will help elucidate potential community and oxidation patterns. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Value enhancement of municipal organics through the addition of effective microorganisms Occurrence and species richness of mycorrhizal fungi in soil under different management and use Basanti Bandekar, Gordon Price, Marco Aurelio Carbone Carneiro1, Rafaela Alves Fernandes2, Doroteia Alves Ferreira3, Orivaldo Jose Saggin-Junior4, Sidney Luiz Stürmer5, Helder Barbosa Paulino6, José Oswaldo Siqueira1 Dalhousie University Large amount of source separated organic (SSO) waste are generated around the world and there are limited management strategies available to reduce their effect on the environment. One of them is composting but it takes a very long time for the SSO material to reach the maturity stage. It is believed that composting time can be reduced by using specialized organisms called ‘Effective microorganisms’ (EM). The current study was aimed at examining the role of EM toward reducing the time of SSO composting by accelerating maturity process. The maturity was measured by respirometry technique (carbon dioxide evolution). The experiment was set up as a 3 x 4 factorial design with three levels of composting stages (stage 1, stage 2 and stage 3) and four levels of inoculants (two commercial inoculants, an active compost and a control). The EM had a significant effect on stage two and no significant effect on stage one and three was found. The maturity testing results showed that the carbon dioxide evolution fulfilled the Canadian Council of Ministers for the Environment guidelines as the carbon dioxide value at the end of the composting period was less than 4 mg of CO2-C/g of organic matter/day. 159 1 Universidade Federal de Lavras Universidade Federal de São Carlos 3 Universidade Federal de São Paulo 4 Embrapa Agrobiologia 5 Universidade Regional de Blumenau 6 Universidade Federal de Goiás 2 This study aimed to assess the impact of different land use systems occuring under a red Latosol in a tropical savanna biome in Brazil (“Cerrado”) on the spore density and richness of AMF. Ten soil samples and roots were obtained from riparian forest, pasture, no tillage, and coffee plantation in dry and wet season. Spores were extracted, counted and identified from field soils and roots were clarified to assess mycorrhizal colonization. A total of 42 AMF species was detected in the all four areas. The genus Acaulospora had the largest number of species (18), followed by Glomus (06) and Gigaspora (05). Gigaspora decipiens and Gigaspora margarita were present in all areas, regardless of the sample period. Gigaspora decipiens was the most frequent species recovered and contributed to the majority of spores in coffee plantations and riparian forest. Cetraspora pellucida was dominant in the area of no tillage and Acaulospora tuberculata in the pasture. Low species richness was detected under coffee plantations with AMF communities dominated almost exclusively by members of Gigasporaceae. We concluded that management adopted in the coffee plantation area caused a reduction in species richness of AMF and promoted a dominance of only one AMF family for the area with pasture. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil hydrogenovorous bacteria – The rare biosphere in action mitigates the global emissions of atmospheric H2 Endophytic bacteria from wheat plants could be useful for Se biofortification and Gaeumannomyces graminis biocontrol Philippe Constant, Quentin Liot, Sarah PichéChoquette Paola Durán1, Jacquelinne Acuña1, Sharon Viscardi2, Maria de la Luz Mora1 INRS-Institut Armand-Frappier 1 Scientific and Technological Bioresource Nucleous Università degli Studi di Napoli Federico II 2 Despite their low abundance, atmospheric trace gases are controlling complex processes modulating both the self-cleaning capacity of the atmosphere and the Earth's radiation budget. Soil microorganisms showing a high affinity for trace gases control the atmospheric balance of these gases by mitigating their global emissions. It is currently very difficult to predict the impact of global change on the biogeochemical function of these micro-organisms, for which the identity and ecophysiology remain largely unknown. Studies combining the identification and characterization of microorganisms scavenging trace gases are thus essential to understand, protect and exploit their biogeochemical functions. This presentation will outline the latest developments into the microbiogeochemistry of atmospheric hydrogen (H2). Soil hydrogenovorous bacteria (SOB) and their high-affinity hydrogenase scavenging atmospheric H2 will be presented. Soil and genomic database surveys led us to discover that the ability to oxidize atmospheric H2 is unevenly distributed in Actinobacteria, Acidobacteria, Proteobacteria and Chloroflexi. Using Streptomyces avermitilis as a model SOB, we have demonstrated that genetic inactivation of high affinity hydrogenase resulted to a dramatic loss of spore viability. Transcriptomic analysis of S. avermitilis exposed to controlled atmosphere unveiled that availability of H2 altered the expression of genes encoding components of the respiratory chain as well as genes encoding permeases involved in nutrient transports and proteins involved in the synthesis of antibiotics. The ecological relevance of these findings suggesting a role for H2 in cell fitness and competition was tested in soil. Soil H2 exposure resulted to a significant alteration of the distribution of several members of the rare biosphere in addition to modify the structure of the interactions among the members of the microbial communities. The coming challenges to elucidate the fate and the ecological importance of the soil uptake of atmospheric H2 will be presented to conclude the presentation. 160 In recent studies we are showed that some microorganisms as bacteria and arbuscular mycorrhizal fungi can be used as biotechnological tools for enhance the Se content in plants. In this study, endophytic bacteria (Acinetobacter sp. E6.2 and Bacillus sp. E5) were isolated from seleniumsupplemented wheat plants and were characterized in terms of Se accumulation and capacity of biocontrol of Gaeumannomyces graminis var tritici (Ggt), the main pathogen of southern Chile. Both strains were highly tolerant to elevated selenium concentration (ranged from 60 to 120 mM, respectively), and showed potential plant-growth-promoting capabilities (auxin and siderophore production, phytate mineralization, and tricalcium phosphate solubilization). In terms of Se species we found that mainly Acinetobacter sp. E6.2 produced elevated amounts of SeMet and SeMeSeCys (10 and 3.77 mg kg-1, respectively), however highly stable NanoSe (Z potential around -40 mV) was the main Se form found in both inoculums. The size of NanoSe from Acinetobacter sp. was major than Bacillus sp. along the time (i.e. 213 ± 3.4 nm and 169 ± 0.92 nm, respectively at 24h). In addition, Se supplementation in bacteria no produced an oxidative stress measured by antioxidant activity (SOD and CAT) and neither affected the tolerance to water deficit due to similar proline and IAA production. Respect to pathogen biocontrol Acinetobacter sp was able to inhibit 100% the pathogen development, whereas 30% was inhibit by Bacillus strains. Our results validate the potential use of these endophytic bacteria inoculums for Se biofortification and Ggt biocontrol. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The Global Soil Biodiversity Initiative The role of microorganisms in a heavy metal polluted site in Mexico T.D. Fraser, D.H. Wall José Abraham Garcia Berumen1, S.A. Covarrubias1, Maria Maldonado Vega2, Juan José Peña Cabriales1 Colorado State University, School of Global Environmental Sustainability The Global Soil Biodiversity Initiative (GSBI) was established in 2011 with the goal of advancing the knowledge of soil biodiversity science. Although it is well established that soil organisms provide essential services including decomposition of organic matter, nutrient cycling, cleansing of water, and regulation of pests, the complex relationships in soil are often overlooked in management and policy decisions. Scientists investigating life in the soil emphasize the critical role of soil biodiversity at all trophic levels to soil functioning and plant production. The GSBI is currently facilitating several initiatives including: a data synthesis working group to bring together soil biodiversity data, early-career scientists creating a network of emerging scientists from around the world, an urban working group to highlight the importance of soil organisms in populated areas, a group interested in the social and cultural values of soil biodiversity and an education section to establish creative methods to deliver this information to a wider audience of all ages. In addition, networking among different groups specifically interested in protozoa, soil fauna, and functional groups across all soil taxa are being established. The GSBI aims to increase the implementation of findings on the benefits of soil biodiversity and identify ways to restore, conserve and promote it. 161 1 Centro de Investigación y de Estudios Avanzados (IPN)Departamento de Biotecnología y Bioquímica 2 Dirección de Planeación, Hospital de Alta Especialidad del Bajío Mining activities in Mexico contribute to 5% of gross domestic product, with the highest worldwide silver production. Mining started in the XVI century in cities like Zacatecas and Guadalupe. The process of silver and gold recovery was not efficient and waste products, also called “jales mineros”, rich in toxic heavy metals such as mercury (Hg), arsenic (As) and lead (Pb), were accumulated in the “Guadalupe Valley” and “the Zacatecana lagoon”. Some reports indicate heavy metal concentrations in human blood, soil and crops in the study area. However, the microbial activity and its relationship with heavy metals has not been studied. We inferred that soil microorganisms are responsible for heavy metal dynamics in this site. Soil and water from Zacatecana lagoon area were sampled on June 2014 for a chemical and microbial analysis. The soil corresponds to a clay loam, with a basic pH of 8.3, and high electrical conductivity (EC) of 2.13 dS m-1. Water has a basic pH of 9.0 and EC of 0.52 dS m-1. High heavy metal concentration was found in the northeast zone of the Zacatecana lagoon. The total heavy metals concentration in soil (mg Kg -1) are 2187.0 ± 1241.2 for Pb, 238.6 ± 317.7 for Hg and 164.7 ± 70.4 for As. In water, concentration (mg L-1) is 0.68 ± 0.1 for As, 0.40 ± 0.0 for Hg and 0.28 ± 0.1 for Pb. The microbial activity of soil, measured as O2 mg Kg-1 consumed, is inverse to high metal concentration. Isolated bacteria from soil and rhizosphere plants mainly belong to Pseudomonas and Bacillus genera, and have shown siderophore production, phosphate solubilization and heavy metal resistance to 1 mM of Pb, 0.5 mM of As and 0.01 mM of Hg. Studies of the microorganisms in chemical transformations of heavy metals in soil are in progress. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Does land use-intensity change microbial abundance and function on organo-mineral surfaces in grassland soils? FLOGging a dead horse: linking decomposed organic matter carbon to nitrogen cycling in agroecosystems Aurelia Gebala, Sven Marhan, Thilo Rennert, Ellen Kandeler Daniel Gillis1, Gordon Price2, University of Hohenheim, Soil Science and Land Evaluation The detritus- and rhizosphere, as well as minerals and organo-mineral complexes are microbial “hot spots” in soils. The colonization of these microhabitats mainly depends on biotic and abiotic soil properties. Mechanisms which drive initial microbial colonization processes of mineral surfaces in natural grassland soils are poorly understood. Further, there is still a debate whether bacteria, archaea and fungi started to feed on root litter resources at the same time or if their activity occurs at different successional stages. Within the framework of the Biodiversity Exploratories, two research questions were addressed: 1) Who are the key players in the detritivore pathway in grassland soils under different land-use intensity, and 2) Who is able to colonize the mineral surfaces and profits most from the available resources? A randomized microcosm field experiment was established on grassland sites at the Swabian Alb (Baden-Württemberg, Germany) in September 2014. Experimental sites differ in land-use intensity (LUI) with 5 sites with low and 5 with high LUIIndex. Microcosms were filled with a mineral mixture consisted of: 71.4 % Illite, 9.6 % Goethite, 17 % QuartzSilt and 2 % Quartz-Sand, as well as double labeled roots of Dactylis glomerata/ Lolium perenne (13.1 atom % C-13 and 31.1 atom % N-15). Sampling of microcosms, adjacent soil and plants above the microcosms are performed after 1, 2, 6, 12 and 18 month. First results from minerals taken after 1 and 2 month indicate a stimulation of microbial biomass carbon about 8 % at sites with low and 14 % at sites with high land-use intensity. Analyzes of microbial community structure using PLFA and qPCR, and microbial function (enzyme activities using MUF substrates and nutrient limitations using oxygen consumption measurements) are currently under way and will show the relative importance of land-use intensity on microbial colonization strategies and feeding preferences. 162 1 McGill University, Bioresource Engineering Dalhousie University, Engineering 2 A model linking soil carbon mineralization and nitrogen mineralization-immobilization (FLOG-CN) was developed and applied to a collection of 70 paired C and N soil datasets. Commonly used compartmental models of C and N based on first-order kinetics do not account for a latency period whereby depolymerization of complex substrates, such as proteins, by exoenzymes is required before both C and N can be mineralized from them, and that this is accomplished by a specialized group of organisms. The FLOG-CN model accounts for this, and provides an interpretive and predictive framework to quantify C and N dynamics following fresh organic matter additions to soil. Our paper outlines a modelling approach coupling C and N mineralization using a global collection of soil incubation datasets, totaling 1572 C and 955 N data points with incubation temperatures ranging from 15 to 30°C, amendment C:N ratios ranging from 5.9 to 64.5, and in soils from nine countries with soil C concentrations ranging from 4.6 to 23 mg g-1. A consequent meta-analysis identified how environmental variables and substrate stoichiometry influence the timing and quantity of C and N mineralization. Temperature, soil pH, soil C concentration, and amendment N:C were sufficient to predict all model parameters, which improves forecasting carbon and nitrogen release in response to organic matter decomposition under changing climatic conditions. The analysis also yielded an independent estimation of the Threshold Element Ratio (TER) of carbon to nitrogen for microbial decomposition of organic matter, corroborating reports from a number of other researchers working in other distinct managed landscapes. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Influence of environmental disturbance on microfungal communities in Israeli soils Chronic N and nutrient loading in a bog: A peek into the microbial black box Isabella Grishkan Galen Guo1, Tim Moore2, Jill Bubier3, Tuula Larmola4, Erik Lilleskov5, L. Jamie Lamit5, Nadia Myckytzuk1, Nathan Basiliko1 University of Haifa, Evolution Soil microfungi with their huge variety of enzymatic properties are essential elements of ecosystems serving as decomposers of organic matter and participating in the aggregation of soil particles. Due to high adaptability, fungi may easily colonize new environments created by anthropogenic activities. In Israel, such activity as cattle grazing is characteristic for different regions. Another kind of strong environmental disturbance – fires, occur periodically during summer and transition seasons. In order to examine grazing- and fire-related variations in soil microfungal communities, studies were performed in the sites located at Golan Height, Upper Galilee (both under grazing), and on Mount Carmel (after fire). Microfungi were detected by the culture-based soil dilution plate method, and composition, structure, and diversity characteristics of the disturbed communities were examined in comparison with the non-disturbed communities. The soils of the grazed sites had poorer species composition – obviously due to the monotonous weed vegetation and soil degradation. This consequence of intensive agricultural usage also lowered the heterogeneity and equitability of the microfungal communities because of the superdominance of fastreproducing Penicillium aurantiogriseum or P. simplicissimum accompanied by frequent occurrence of very fast growing Trichoderma koningii. It accorded with the known tendency showing that disturbance impact (especially soil degradation) might simplify microfungal community structure and decrease its diversity level. The fire supported abundant development of fast-growing mycoparasitic species (Clonostachys rosea and Trichoderma spp.) and caused significant decrease in species richness. The variations in community composition were much more expressed under native oak vegetation as compared to the pine trees. In the oak burned soils, the contribution of "mesic" Penicillium spp., was markedly lower, while the contribution of "xeric" melanin-containing species, was higher than in the unburned communities. Such variations can be considered as a community response to the fire-related decrease in water and nutrient content in the burned soils. 163 1 Laurentian University McGill University 3 Mount Holyoke College 4 University of Helsinki 5 USDA Forest Service 2 Peatlands account for just 3% of the Earth’s terrestrial surface and have stored more than one third of atmospheric C over the Holocene epoch. Flooded, anoxic conditions and nutrient poor soils that have facilitated sequestration of CO2 also lead to the production and emissions of the highly potent greenhouse gas, CH4. Human activities such as agriculture and fossil fuel burning have increased reactive atmospheric N to record levels over the past century. N deposition can provide a limiting nutrient to these systems, and although net primary production increases, high N deposition has also been associated with plant community shifts and increased decomposition rates that lead to greater emission of both CO2 and CH4 via the disruption of natural microbial communities. For example, inorganic N can selectively inhibit CH4 monooxygenases in methanotrophic bacteria. By examining peat soils from randomized, replicated treatment plots in the longest running simulated chronic N deposition experiment at the Mer Bleue Bog, our objective is to characterize how increased deposition and resulting observed vegetation shifts impact diversity and abundance of broad-spectrum microbial decomposers and methanotrophs. Using community fingerprinting (TRFLP and high throughput amplicon sequencing on the Illumina MiSeq platform) and qPCR of SSU rRNA genes, our data show that the microbial community structure has changed as a response to the vegetation shift away from a Sphagnum- moss dominated community. However, we found no changes in methanotroph communities by analyzing sequences and abundances (pyrosequencing of the pmoA and qPCR of pmoA and mmoX) of CH4 monooxygenases. Additionally, physiological incubation experiments also indicated no significant impact of N or combined nutrients on CH4 consumption rates. Our results provide insight on the possible causes of higher CO2 release and little impact on CH4 fluxes measured in situ in the same experimental plots. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial Community Study in the Sediment of Oostanaula Creek Watershed Bacterial diversity and profile characteristics of urban soils in New York City Yanchong Huangfu1, Shawn Hawkins1, Alice Layton2, Forbes Walker1, Dan Williams3 Hermine Huot1, Alonso Córdoba2, Jessica Joyner2, Theodore Muth2, Richard Shaw3, Roxanne Walker1, Mike Wilson3, Zonghqi Cheng1 1 University of Tennessee, Biosystems Engineering & Soil Science 2 University of Tennessee, Earth & Planetary Sciences 3 University of Tennessee, the Center for Environmental Biotechnology Removal of Oostanaula Creek from the Tennessee 303(d) list will require too much efforts in reducing concentration of pathogen indicator (E. coli), Sedimentation, and phosphate. The current restoration plan focuses on promoting Best Management Practice (BMP) to reduce sediments caused by fecal pollution from the activities associated with cattle. However, to effectively implement BMPs, it is critical to identify the sediments caused in specific locations of non-point source pollution problems in the Oostanaula Creek Watershed (OCW). This research focuses on the identification of the sources of suspended and deposited sediment in OCW by Next Generation Sequencing technique. Totally, 70 sediment samples, originating from pasture soils, cattle walkways and creek banks, were collected throughout the upstream and downstream of OCW at the city of Athens. The hypothesis of this study is that the microbial communities among different types of sediment samples are different. After DNA extractions and purification of the sediment samples, 16S rRNA gene amplicons were produced, purified and sequenced on a MiSeq sequencer for high-throughput sequencing analysis. The image data are further analyzed and categorized according to different types of soils by QIIME, MGRAST and R package. In addition, statistical analysis, like alpha diversity and beta diversity, are currently performed to support the characterization of sediments in OCW. A total 7,565,516 Illumina sequencing reads, comprised of 72,980 OTUs, were generated from the 30 samples of Oostanaula sediment, cattle manure and poultry litter. The median and the mean sequencing reads for all of the samples are 160,529 and 252,183. Finally, the results indicated Sediment MST technology can help matching the consortium of bacteria in sediment materials and contaminating sediment to suggest the origin of sediment pollution. 164 1 University of New York, Earth and Environmental Sciences University of New York, Biology 3 USDA – Natural Resources Conservation Service 2 The understanding of urban soils is becoming increasingly important as they are involved in many urban management issues. The development of urban soils is likely to be influenced by human activities, through the production of human-made materials, soil excavation, mixing or contamination. These types of disturbance can change dynamic soil properties (DSP) and the soil profile development. Soil microorganisms are sensitive to soil conditions and may respond to these disturbances. This project investigates the bacterial diversity, in correlation with DSPs, down through the profile of a range of urban soils collected across New York City. These are characterized by different parent materials, vegetative cover and moisture regime. Eight pedons were described and sampled. Four soils are formed in naturally deposited materials (NDM) (e.g. till, outwash) and the another are formed in human-altered and human-transported materials (HAHTM) (e.g. coal ash, construction debris). DSPs examined included pH, texture, organic C, salt and metals. Bacterial diversity was analyzed by extracting DNA and sequencing the 16S rRNA gene with Illumina MiSeq. Data were processed using QIIME and additional statistical tests in R. The HAHTM soils had less developed profiles (A-C type) than NDM soils (A-B-C type). Comparatively, HAHTM soils and the serpentine till soil were characterized by higher pH values, especially when carbonated artifacts were present, higher average metal content and higher coarse fragment content. Bacterial diversity was comparable even slightly higher in HAHTM soils than NDM soils. Some differences in the bacterial community structure are observed between these two categories of soils. The main drivers of the bacterial diversity were pH and Zn, two properties influenced by human activities (e.g. artifacts, atmospheric deposits). Bacterial community structure changed with depth but this trend seemed to be more apparent for NDM soils, possibly due to greater differentiation of horizons and hence of microorganism habitats. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 PAH Bioremediation for Ecological Sustainability The effect of rotational and continuous grazing on soil microbiological properties: comparing the savanna and grassland biome Jamshid Jazestani, Shiv Prasher Elmarie Kotzé1, A. Sandhage-Hofmann2, C.C. Du Preez1, W. Amelung2, McGill University, Bioresource Engineering Bacterial isolates from nineteen different soils contaminated with a large range of organic pollutants, were tested for their ability to metabolise selected recalcitrant PAHs, namely naphthalene, anthracene, phenanthrene, fluorene, fluoranthene and pyrene, as their sole energy and carbon source. Using serial dilution and spread-plate techniques on solid MSM-agarose (DNA-grade, Bio-Rad) medium, containing phenanthrene (PAH) as sole carbon source, 228 phenanthrene-degrading bacterial strains were isolated from 12 petroleum-contaminated soil samples. Out of the 228 strains, 60 positive colonies that presented a clear zone in the phenanthrene precipitate, were selected and purified for further characterization. All 60 positive colonies were routinely subcultured at ambient temperature (25°C) on YTS1000 - agarose plates. A DNA-DNA (Southern) Hybridization Technique was used to identify 14 colonies, among the 60 isolated colonies, which exhibited a potential for naphthalenedegradation (ndoB Positive). To further screen for the biodegradation capacity of the fourteen isolated bacterial strains, standard aerobic liquid serum bottle microcosms were set up for quantitative radioactive tracer analysis of the biodegradation and cumulative percent mineralization of the six PAHs compounds. One of the PAH-degrading bacterial strains namely S65, isolated from a jet-fuel contaminated site at the Sept-Iles airport (Sept-Iles, Quebec, Canada), on the north shore of the St. Lawrence river, was able to mineralize selected PAH compounds. The S65 strain was routinely subcultured at ambient temperature (25°C) on YTS1000 - agarose nutrient agar plates. The PAHs mineralization experiments with the S65 strain showed high cumulative percent mineralization for pyrene (61%), phenanthrene (61%), and fluoranthene (24%), as sole carbon and energy sources, but no significant degradation of naphthalene, anthracene or fluorene. 165 1 University of the Free State, Soil, Crop and Climate Sciences 2 University of Bonn, Crop Science and Resource Conservation Rangelands play an important role in ecosystem structure and function, and can be highly variable as a result of rangeland management systems. Therefore, long-term sustainability of rangeland management systems, whether associated with structural stability or nutrient dynamics, is among others dependent on the maintenance of soil microbiological properties. In this study we examined the response of soil microbiological and associated properties due to rangeland management, in two different ecosystems with different climate, vegetation and soil. For this purpose soils were sampled under continuous and rotational grazing systems along a gradient with increasing grazing pressure. Results showed that the clayey grassland ecosystem had higher values for all measured microbiological properties compared to the sandy savanna ecosystem, regardless of rangeland management practices, indicating that soil texture played a significant role in microbial communities. Results further indicated that soil microbiological properties are more sensitive to changes in land use compared to chemical or physical properties. Decreasing the grazing pressure on rangelands, such as commercial farmers practicing rotational grazing, can stimulate microbial-mediated nutrient mineralization with positive consequences on plant growth. Within the clayey grassland ecosystem enzyme activities as well as PLFAs responded positively when reducing the grazing pressure, whereas in the sandy savanna ecosystem this was not necessarily the case. In this study grazing mainly affected soil microbiological properties through the direct effect of animal trampling and urine and dung contributions, and indirectly through its effect on perennial grass cover, as was evident in the piospheres of the rangeland management systems. Overall the sandy soil of the savanna ecosystem seemed to be more resilient to degradation over the long-term, and less over the short-term, whereas the clayey soil of the grassland ecosystem showed evidence of resilience over the short-term, and less over the long-term. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Body size is a sensitive trait-based indicator of soil nematode community response to fertilization in rice and wheat agroecosystems ， Ting Liu1 2, Joann Whalen2, Huixin Li1 1 2 Nanjing Agricultural University McGill University, Natural Resource Sciences Nematode body size is a trait that could be responsive to environmental changes, such as agricultural management practices, and adopted as a standard trait-based indicator in soil community analysis. Our study investigated how body size in the nematode community responded to fertilization in a doublecropping system with paddy rice and upland wheat. Four fertilizer treatments were examined: an unfertilized control (CK), chemical fertilizer (CF), manure plus chemical fertilizer (MCF) and manure plus straw plus chemical fertilizer (MSCF). The communityweighted mean (CWM) of body size was the trait-based indicator used for nematode community analysis. A trend of increasing body size in fertilized plots was observed for most genera, with a relatively small increase in the size of small-bodied bacterivores and fungivores and a relatively large increase in the size of large-bodied omnivores. Fertilized plots had significantly greater CWM of body size than the CK treatment, although total nematode abundance increased significantly in the MSCF treatment only. Discriminant and multiple regression analyses showed that CWM of body size was positively correlated with the soil organic C, total N, available P and available K concentrations, which responded to fertilizer inputs. In contrast, soil fertility was weakly related to total body size in the wheat phase and the following abundancebased indicators: Margalef′s richness index, Shannon′s diversity index, summed maturity index (∑MI) and enrichment index (EI) in both phases. Since fertilization resulted in larger body size but no other change in the nematode community (i.e. diversity and abundance were generally unaffected by fertilization), this implies that nematodes have a plastic growth habit that does not necessarily result in greater reproduction or fitness of offspring. We suggest that CWM of body size is a reliable trait-based indicator of the soil nematode community response to fertilization, but this requires further testing across a wider range of fertilized agroecosystems. 166 Indications of shifting microbial communities associated with growing biomass crops on marginal lands in southern Ontario Tolulope Mafa-Attoye, Naresh Thevathasan, Andrew Gordon and Kari Dunfield. School of Environmental Science, University of Guelph. In Canada, purpose grown biomass is derived from herbaceous species such as miscanthus (Miscanthus giganteus) and switchgrass (Panicum virgatum), as well as woody species such as poplar (Populus spp.) and willow (Salix spp.). Feedstock derived from these biomass crops are used in the production of biofuels. Soil microorganisms in biomass crop ecosystems play very important roles in soil fertility and cycling of nutrients. Their relevance to biomass crop productivity, soil health and sustainability cannot be over emphasized. This study assessed the distribution of soil microorganisms (bacteria and fungi) in biomass crops planted in nitrogen (N) fertilized and unfertilized plots. Four biomass crops: poplar, switchgrass, miscanthus and willow were planted in 2009 on a marginal land in Guelph Ontario Canada. Half the plots were fertilized in a split-plot design with 4 field replicates. In fall 2014 and spring 2015, soil samples were collected at a depth of 15 cm for organic carbon, total nitrogen and microbial analyses. DNA was extracted from fresh soil, and total bacterial (16S rDNA), fungal communities (ITS), and arbuscular mycorrhizal fungi (AMF) were enumerated using the quantitative PCR (qPCR). Data was analyzed in SAS using ANOVA. Results showed that there was no change in soil total N due to species or fertilizer treatment, at the time of sampling, but that organic carbon accumulated more quickly in switchgrass and miscanthus plots, compared to poplar, since establishment in 2009. Total bacteria populations did not differ across species of biomass crops; however, the bacterial community was higher in N fertilized plots. Interestingly the fungal communities were significantly higher in the poplar and willow plots, resulting in lower bacterial: fungal ratios associated with poplar and willow compared to switchgrass and miscanthus. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil microorganisms and enzyme activity at different levels of SOM complexity Soil microbial community structure in the sacred groves of Epirus, Greece Carolina Merino, Francisco Matus Nikolaos Monokrousos12, Magdi Mola2, Kalliopi Stara1, Rigas Tsiakiris3, John Halley1 Departamento Ciencias Químicas y Recursos Naturales, Universidad de La Frontera Biodiversity of soil microbial communities has important implications for the stability and functioning of soil organic carbon fluxes. In this study, we determined the activity of microorganism at different level of carbon pool in different physical fractions (light 250-2000 µm, intermediate 53-250 µm and mineral < 53 µm) of allophanic and metamorphic temperate rain forest soils. All soils and fractions were incubated for short incubation periods (30 days). We determine the enzymes activates (dehydrogenase, α-glucosidase, urease and phosphatases) as well as C-microbial biomass, microbial parameters (carbohydrates and reducing sugar) and cellulosic and ligninolytic bacteria’s and fungi counting at five samplings times. The results indicated that all physical fraction in the two soils had an impact on enzymes activities, carbohydrates, microbial biomass and microbial growth. The soil alone did not explain the differences in microbiological parameters, except reducing sugars. The microbial biomass was the highest in MF of metamorphic soil and the lowest in the LF of both soils. Our result were attributed to different C pool complexity in the physical fractions from the two soils. This suggest distintic mineralization capacities from soil microorganism due to different amount of available C and essential nutrients. 167 1 Department of Biological Applications and Technology, University of Ioannina, Greece 2 Department of Ecology, School of Biology, Aristotle University Thessaloniki, Greece 3 Department of Forestry, Ioannina, Greece A network of sacred groves (forests protected and conserved for religious reasons for centuries) is found near chapels or shrines in the mountainous areas of Epirus, Greece. These groves are believed to have played an important role in biodiversity conservation. The aim of this study was to investigate the structure of the soil microbial community under natural stands of various forest types in sacred groves, and compare them with those of conventionally managed forest sites nearby that serve as controls. Soil samples were collected in September 2013. Eight sacred grove stands were selected along with their respective eight control sites, two for each of four different forest types: broadleaf oak, mixed broadleaf, evergreen and pine forest. Phospholipid fatty acids (PLFAs) analysis was used for the estimation of the composition of soil microbial community (Gram+ and Gram- bacteria, actinomycetes, fungi, total bacterial and microbial biomass). Sacred groves presented higher values for all microbial categories compared to their control sites. Exceptions to this pattern were the pine forests where no significant differentiation was recorded. Moreover, among sacred forests, broadleaf stands exhibited the highest values for all microbial variables, followed by the evergreen stands, while the pine forests exhibited the lowest. By contrast, in the control sites no such differentiation was recorded. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Improvement of wine terroir management according to biogeochemical cycle of nitrogen in soil Soil microbial responses to wood ash addition and forest fire in managed Ontario forests Nassr Najat1, Aude Langenfeld1, Mohammed Benbrahim1, Lionel Ley2, Laurent Deliere3, Jean Pascal Goutouly4, David Lafond5, Myriam Drolet1, Marie Thiollet-Scholtus6 Genevieve Noyce1, Roberta Fulthorpe1, Adam Gorgoleski2, Paul Hazlett3, Trevor Jones4, Honghi Tran5, Nathan Basiliko6 1 RITTMO Agroenvironnement 2 INRA-UE0871 3 INRA-UMR 1065 4 INRA-UMR 1287 5 IFV Institut Francais de la Vigne et du Vin 6 INRA-UE1117 Good wine terroir production implies a well-balanced Biogeochemical Cycle of Nitrogen (BCN) at field level i.e. in soil and in plant. Nitrogen is very important for grape quality and soil sustainability. The mineralization of organic nitrogen is the main source of mineral nitrogen for the vine. This mineralization depends mainly on the soil microbial activity. This study is focused on the functional microbial populations implicated in the BCN, in particular nitrifying bacteria. An experimental network with 6 vine sites located in Atlantic coast (Loire valley and Bordeaux) and in NorthEast (Alsace) of France has been set up since 2012. These vine sites represent a diversity of environmental factors (i.e. soil and climate). The adopted approach is based on the measure of several indicators to assess nitrogen dynamic in soil, i.e. nitrogen mineralization, regarding microbial biomass and activity. Statistical analyses are performed to determine the relationship between biological indicator and nitrogen mineralization regarding farmer’s practices. The variability of the BCN indicators seems to be correlated to the physical and chemical parameters in the soil of the field. For all the sites, the bacterial biomass is correlated to the rate and kinetic of nitrogen in soil, however this bioindicator depends also on others parameters. Moreover, the functional bacterial diversity depends on the soil organic matter content. Differences in the bacterial biomass and kinetic of nitrogen mineralization are observed between the sites with clayey (Loire valley site) and sandy soils (Bordeaux site). In some tested vine systems, effects on bacterial activity and nitrogen dynamic are also observed depending on the farmer’s practices: soil tillage, reduction of inputs, i.e. pesticides and fertilizers, and soil cover management between rows. The BCN indicators seem to be strong to assess the dynamics of the nitrogen in various sites underline the functional diversity of the soils. These BCN indicators could help to manage the dynamics of the nitrogen and the nitrogenous nutrition of the vine in innovative sites/systems with various farmer’s practices. 168 1 University of Toronto, Physical and Environmental Sciences University of Toronto, Forestry 3 Canadian Forest Service, Great Lakes Forestry Centre 4 Ontario Ministry of Natural Resources, Forest Research Institute 5 University of Toronto, Chemical Engineering and Applied Chemistry 6 Laurentian University, Biology & Vale Living with Lakes Center 2 Wood ash, a byproduct of biomass boilers, is being considered as a soil amendment for increasing the productivity of forests and improving overall forest health, in response to soil acidification and nutrient depletion. Given the vital roles of soil microbial communities in forest nutrient dynamics, characterizing microbial responses is crucial for predicting the overall ecosystem response to wood ash additions. In this study, soil chemistry and microbial community composition were studied after wood ash addition to a recently clear-cut boreal forest in Northeastern Ontario and an uneven-aged single-tree-selection-logged Great Lakes/St. Lawrence forest in Central Ontario. The soil microbial community in a recently-burned boreal forest stand adjacent to the boreal forest ash trials was also characterized. At the boreal site, ash addition as low as 0.7 Mg per ha increased soil pH, decreased the ratio of fungi to bacteria in the soil microbial community, and significantly altered the bacterial and overall eukaryotic community composition, but had no effect on the composition of the soil fungal community or on microbial biomass and respiration rates. There was no additional effect of increasing ash addition from 0.7 to 5.7 Mg per ha. At the Great Lakes/St. Lawrence forest site, ash addition also increased soil pH and bacterial diversity. In contrast, the forest fire had no pH effects after one year, but significantly altered the composition of soil bacterial and eukaryotic communities. Overall, the strongest driver of microbial community composition was the forest type, rather than the addition of ash. This implies that wood ash has minimal negative effects on the composition and functioning of the soil microbial community, especially when compared to the effects of naturally-occurring fires. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial community structures in different horizontal sub-surface flow constructed wetlands enriched with biochar as revealed by 454-pyrosequencing analysis Selmene Ouertani1, Steeve Pepin1, Hani Antoun1, Hela Selmi1, Martine Dorais2, 1 Université Laval, Centre de recherche et d’innovation des végétaux 2 Université Laval, AAFC Microbial communities are essential for treatment processes in constructed wetlands (CW). Biochar is known, when added to soil, to induce modifications in the structure and composition of microbial communities through many mechanisms. In this study, we have examined, using the 454-pyrosequencing technology, the microbial community composition and abundance of substrate from six different types (with six repetitions) of horizontal sub-surface flow constructed wetlands planted with Typha latifolia (two substrates: sand or gravel and three biochar treatments: without biochar, with biochar incorporated and with filter of biochar) and their respective effluents. In total, 36100 and 23884 effective sequences of the 16S rRNA gene were generated from CW's substrate and effluent samples, respectively. Our results have shown that CW substrates and effluents had different diversity indexes, expressed by either the Chao or Shannon’s diversity index. For substrate samples, bacterial diversity was increased by biochar amendment in gravel treatments, contrary to sand treatments where diversity indexes were decreased by biochar. Proteobacteria was found to be the dominant phylum in all substrate samples, followed by Actinobacteria and Bacteroidetes. For effluent samples, Proteobacteria was the predominant phylum followed by Bacteroidetes. The microbial community composition for CWs substrate and effluent samples were also outlined at the class and genus levels and many differences were observed between gravel and sand treatments and biochar amended and non-biochar amended treatments. A comparison of microbial communities between substrate and its respective effluent for each treatment was carried out. For gravel treatments, higher diversities were observed in effluent samples which was not always the case for the treatments with sand. Many shared Operational Taxonomic Units (OTU) between substrate and effluent samples were also identified. Understanding the effect of biochar on CW's microbial populations will be very useful in the study and the control of CW's performance in treating greenhouse effluents. 169 Microbial Road Kill: How Roads Impact Bacterial Activity and Diversity Jennifer Pichette, Michael Carson, Sean Boyle, Graeme Spiers, Nathan Basiliko Laurentian University Soil bacteria have an immense influence on ecosystem processes. They are responsible for cycling nitrogen and carbon, acquiring nutrients for plants and soil weathering and formation. Roads are linked to the emission of many pollutants originating from car tires, brake linings and fuel combustion, and also from the chemical composition of the road infrastructure itself. Storm runoff and dry deposition (a.k.a. dust) can cause the contamination of soils and impact ecosystem health. Heavy metal contamination has been shown to reduce rates of litter decomposition and soil respiration, bacterial nitrogen mineralization and fixation, and bacterial enzyme activity. The purpose of this study was to examine how road pollutants influence bacterial activity and diversity around roads of varying traffic volume, and determine their road-effect zone. We measured a variety of soil properties such as pH, bulk density, moisture content, soil temperature, metal and nutrient concentrations and organic matter content. We also measured the bacterial biomass and respiration rates and characterized the bacterial community composition using high throughput amplicon sequencing of biomarker genes. We predicted a gradient within the road effect zone in which microbial diversity, biomass, and activity decreased as sample plots approached the road edge. Regardless of road size, we found that the soils closest to the roads were very alkaline (pH~9-10) and had less moisture, higher bulk densities and very low nutrients and organic matter (i.e. both physical and chemical properties were impacted). Similarly, soil bacterial communities displayed minimal respiration rates, reduced biomass, and altered community structure approaching the road edge. Taken together, our results indicate a significant impact of roads on neighbouring soil chemistry, physical traits, and bacterial community structure and abundance with implications for altered nutrient cycling and ecosystem functioning. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Isolation and characterization of filamentous fungi from forest soil and their use for biotechnological production of immunomodulatory glycoproteins Baiba Silamikele, Ilze Blake, Anna RamataStunda, Vizma Nikolajeva, Zaiga Petrina, Indrikis Muiznieks University of Latvia, Microbiology and Biotechnology Soil microorganisms are valuable sources of biologically active substances, including antibiotics and enzymes. As comprehensive studies in soil microbiology have been done in recent decades the potential of medical and industrial application of metabolites produced by soil microorganisms is growing. Fungal immunomodulators are widely used for different conditions. Currently most fungi derived immune response modulating agents are isolated from basidiomycetes and little research has been done on isolation and biological activity of immunomodulators from filamentous fungi. Soil fungus Penicillium lanoso-viride strain 8D has been isolated from upper layer (5-20 cm) of podzol soil in Latvia. A glycoprotein fraction possessing AMP deaminase activity has been chromatographically obtained from fungal biomass in its sporulation phase and its immunomodulatory characteristics tested in vitro. Glycoprotein fraction exhibits stimulating activity on peripheral blood mononuclear cells (MNC). Secretion of pro-inflammatory cytokines TNF-a, IL-6 and IL-8 is elevated in a dose dependent manner. In the meantime glycoprotein has modulating activity as it suppresses immune response evoked by bacterial endotoxin and also stimulates production of anti-inflammatory cytokine IL-10. These findings suggest that P.lanosoviride glycoprotein fraction can be used as immune response modulator for variable conditions, including autoimmune diseases. As immune response modulation is important also in treatment of other specific conditions, including neoplastic processes as well as wound healing – changes in secretion of growth factors EGF, FGF-2, VEGF and secretion of IL-8 were analyzed in fibroblasts, keratinocytes and endothelial cells. Dose dependent suppression of VEGF secretion has been observed in dermal fibroblasts and MNCs however in endothelial cells secretion is slightly upregulated. Dose changes were observed also for FGF-2 and IL-8. 170 Phyto-stabilization of Sudbury mine tailings: important microorganisms in naturally colonizing plant rhizospheres Emily Smenderovac, Nathan Basiliko, Nadia Mykytczuk, Daniel Campbell Laurentian University, Living with Lakes Center Reclamation of acid generating mine wastes inevitably requires a vegetation step, preferably with species native to the disturbed area. This restoration goal is supported by transition from a system dominated by chemolithoautotrophic microorganisms to one dominated by chemoorganoheterotrophs, fueled by plant litters and playing roles in "soil' formation. Microbes in the rhizospheres undoubtedly assist plant growth in these acidic and metal rich environments by directly mutualistic interactions or through passive reduction or sequestration of toxic compounds. Here we assessed microbial communities and functioning in naturally recolonizing plant rhizospheres in Sudbury, On Ni-Cu tailings. Tailings rhizospheres (from two tree and one grass species) and uncolonized tailings as well as rhizospheres from the same species in natural soils were collected. Microbial communities were characterized using high throughput (MiSeq) sequencing of rRNA gene amplicons. PCR assays identified presence of functional genes involved in nitrogen and sulfur utilization. Physiological incubations measured rates of microbial activity and tested carbon and nutrient limitations. Soils and tailings were analyzed for total and bioavailable metals and other elements. Key questions this project aims to answer include: Are plant rhizosphere communities unique in 1) bare tailings and 2) natural soils? Are there plant species differences in the tailings? What organisms drive existing differences? What nutrients limit tailings-rhizosphere microbes? How might this inform amendments to further stimulate activity? Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Peatland Microbial Community Structure and Function along a Sulphur and Metal Contamination Gradient in Sudbury, Ontario Shanay Williams-Johnson1,2, Nathan Basiliko1,2, Graeme Spiers1, L. Jamie Lamit3, Erik Lilleskov3, Nadia Mykytzcuk1 1 Laurentian University, Living with Lakes Center and the Department of Biology 2 Laurentian University, Department of Biology 3 US Forest Service and Michigan Technical University The Sudbury, Ontario region has had over a century of metal mining/smelter activity that has led to significant sulphur and metal deposition. This has negatively affected both freshwater and terrestrial ecosystems, including peatlands and potentially the peatland microbial communities. Because they have thick organic soils, at global scales, peatlands are important contributors to the global climate system in their role in regulating terrestrial carbon efflux. At local and regional scales peatlands protect water quality of downstream aquatic ecosystems. Eleven peatland sites (poor to intermediate fens) along a sulphur and metal contamination gradient around Sudbury were chosen in order to study microbial diversity and activities of enzymes that control decomposition and nutrient cycling. The analysis of microbial communities was accomplished via high throughput sequencing of 16S rRNA genes in bacteria and archaea and ribosomal ITS DNA regions in eukaryotic microorganisms on the Illumina MiSeq platform. Polluted sites closest to current and historical smelter deposition had clearly more decomposed surface peat and lost Sphagnum moss vegetation. Rates of microbial enzyme activities, particularly phenoloxidase and peroxidase were elevated in these sites relative to “control” sites upwind from smelters to the northwest of Sudbury. Two potential explanations for this pattern are 1) peat mineralization was stimulated through enhanced sulphate reduction and 2) loss of Sphagnum mosses and related secondary metabolites released constraints on decomposers. Interestingly, despite that the polluted sites have historically received more S deposition than virtually any other environments on earth, control sites were the most acidic, which is consistent with both lower rates of alkalinity-generating sulphur reduction and the presence of H+ generating Sphagnum mosses. The presence of heavy metals (Ni, Cu, As) do not appear to have impeded decomposition in polluted sites relative to controls. In this presentation newly-obtained molecular biomarker data will be integrated with and interpreted in light of microbial activity and soil chemistry patterns. 171 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S4: Organo-Mineral Interactions in Soil 172 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Earthworm population dynamics in no-till corn and soybean agroecosystems in Quebec Zhor Abail, Joann Whalen McGill University, Natural Resource Sciences No-till agroecosystems are widely recognized to support higher earthworm population by creating favorable conditions for earthworms to grow and reproduce. In these systems, crop residues left on the soil surface improve the soil structure and provide a food resource for earthworms. However, the response of earthworm populations to these food inputs depends on residue characteristics. Through this study we aimed to assess earthworm population dynamic in two fields with contrasting crop residue characteristics: corn and soybean residues. These adjacent fields, with similar soil texture (sandy-loam) were located at the Macdonald Research Farm, McGill University, Sainte Anne de Bellevue (Quebec, Canada). They represented both phases of a no-till corn-soybean rotation. Earthworms were collected by handsorting and formalin extraction at approximately biweekly intervals during the spring/early summer 2014 and fall 2014. All earthworms were preserved in 5% formalin, and latter identified to species level, counted and weighed. About 71% of the total earthworms collected were juveniles. A. turgida, A. tuberculata, L. terrestris and A. Chlorotica constitute the dominant mature species in these fields. We also found a few (less than 1% of the earthworm population) A. rosea and A. longa. Earthworm abundance was greater in the soybean field (357±33 individuals m-2) than in the corn field (197±18 individuals m-2), as well as the earthworm biomass (soybean field: 14.4±1.4 g AFDW m-2; soybean field: 8.5±0.8 g AFDW m-2). There were significant (P<0.05, HSD) seasonal fluctuations in earthworm populations and biomass, probably related to soil moisture and temperature conditions. There was higher earthworm abundance and biomass during the fall season in the soybean field than the corn field. We presume this effect is due to food availability from crop residues left in the previous growing season, as the slowly decomposing corn residues were evident in the soybean field but there was virtually no soybean residue remaining in the corn field. 173 Characterization of organic matter in densitysize fractions of organically managed soils by diffuse reflectance infrared Fourier transform spectroscopy combined with NaClO oxidation Masakazu Aoyama Hirosaki University, Agriculture and Life Science Organic management relies on organic inputs as fertilizers and thus results in the accumulation of soil organic matter. The objective of this study was to characterize the organic matter in density-size fractions of soils from a commercial organic farm by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy combined with oxidation with sodium hypochlorite (NaClO). Soil samples were collected from upland fields that had been subjected to different periods and amounts of manure application and from an adjacent meadow that had been received neither organic nor inorganic fertilization for fifteen years. The soil samples were separated into free particulate organic matter (fPOM; < 1.6 g cm-3), occluded particulate organic matter (oPOM; < 1.6 g cm-3), heavy particulate organic matter (hPOM; > 1.6 g cm-3, > 0.053 mm) and mineral associated organic matter (MAOM, > 1.6g cm-3; < 0.053 mm) fractions. DRIFT spectrum was obtained as the difference spectrum between those measured before and after NaClO oxidation. The increase in the amount of organic C under organic management was observed for all the POM fractions. The C-to-N ratio was extraordinary high for the oPOM fraction and decreased in the order fPOM fraction > hPOM fraction > MAOM fraction. The C-to-N ratio of oPOM fraction was lowered by manure application. DRIFT spectroscopy revealed that the chemical properties of the organic matter differed among the fractions. The fPOM fraction was characterized by a high content of lignin, and its content tended to be higher in organically managed soils. For the oPOM and hPOM fractions that contained more microbially processed materials than the fPOM fraction, aliphatic and carboxylic compounds were preferentially accumulated in the light fraction, whereas proteinous compounds were in the heavy fraction. The MAOM fraction was rich in proteinous compounds, but contained few lignin-derived structures. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Nanoclays from Andisols and Cambisols soils: their implication on carbon stabilization potential Effect of Organic and Chemical Fertilizers on yield and Quality Characteristics of Basil (Ocimuom basilicum L.) Marcela Calabi-Floody1, Cornelia Rumpel2, Gabriela Velásquez1, Antonio Violante3, Roland Bol4, Leo Condron5, Maria de la Luz Mora1 Vida Chalavi, Mehdi Chezgi 1 Universidad de la Frontera, Soil Interaction and Natural Resources Biotechnology 2 INRA-UMR, Campus AgroParisTech 3 Università Degli Studi di Napoli Federico II 4 Institute of Bio- and Geosciences, IBG-3 5 Lincoln University, Agriculture and Life Sciences Greenhouse gas (GHG) emissions and their consequent effect on global warming are an issue of global environmental concern. Carbon stabilization and sequestration is one of the ways to mitigate these emissions. Here we evaluated the role of nanoclays isolated from soil on C stabilization in both a C rich Andisols and C depleted Cambisols. Nanoclays were analyzed for size and morphology by transmission electron microscopy (TEM), for elemental composition and molecular composition using pyrolysis-GC/MS. Moreover, nanoclays were treated with H2O2 to isolate stable SOM associated with them. Our result showed better nanoclay extraction efficiency and higher nanoclay yield for Cambisol compared to Andisols, according to their low organic matter content. Nanoclay fractions from both soils showed contrasting size, morphology, surface reactivity and SOM content. Nanoclays in Andisols sequester around 5-folds more C than Cambisols, and stabilized around 6 to 8-folds more C than Cambisols. However, the chemical composition of the associated SOM was similar, illustrating their importance for C sequestration. C stabilization mechanisms of both soils may be different, with nanoscale aggregation being more important in Andisols. We can conclude that independent of the soil type and mineralogy the nanoclay fraction play an important role in C sequestration and stabilization. 174 Sari Agricultural Sciences and Natural Resources University Addition of compost and vermicompost organic fertilizers on soil would improve soil physical conditions, nutrient elements and microorganisms. In present study, the effect of single and the combinations of compost, vermicompost and urea chemical fertilizer on yield and quality characteristics of basil medicinal plant was investigated in a split plot based completely randomized design experiment. Treatments were 6 types of fertilizers, including cow vermicompost, cow compost, vermicompost + urea, compost + urea, urea, no fertilizer (control) for two green and purple basil cultivars. According to the obtained results, the combination of organic fertilizers with urea and organic fertilizers alone did not show any differences regarding plant fresh and dry yield. However, the amount of nitrate residue in leaves was increased in the combination treatments of organic fertilizers with urea. The results showed that the use of organic fertilizer alone did not affect leaf area. However, the combination use of urea chemical fertilizer with compost and vermicompost organic fertilizers increased leaf area as compared with control. Among two cultivars green basil was better than purple one for the most of measured characteristics except having higher nitrate residue. Regarding harvest time, the highest yield and antioxidant capacity were observed on second harvest. The results showed that in all three basil harvests, the least essential oil percentage belonged to urea chemical fertilizer and increased in the combination of urea with compost and vermicompost organic fertilizers. The highest essential oil percentage in all three harvests obtained in compost and vermicompost organic fertilizers. In conclusion, the use of organic fertilizers would positively affect yield and quality of basil plants. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Organic matter content in different size aggregates from an Andisol Fe-C associations and soil organic matter stability in two tropical soils of contrasting parent materials Francisco Contreras1, Elisa Nlro2, Marcela Calabi1, Gabriela Velázquez1, Maria de la Luz Mora1 Elizabeth Coward1, Alain Plante1, Aaron Thompson2 1 1 2 2 Soil organic matter play a key role in phosphorous availability for plants growth, because of that, the aim of this study was to evaluate distribution and relationship between carbon, nitrogen and phosphorus in four aggregate sizes from three series of Chilean Andisols: Puerto Fonck and Piedras Negras under permanent grassland, while Pemehue under cereal crops. Andisols were separated by sieving a soil sample over three sieves (2 mm, 0.25 mm, and 0.053 mm). Carbon and nitrogen content were measured in elemental analyzer (Eurovector EA 3000) and phosphorus for digestion by sodium hipobromite method. Isoelectric point was measured in coarser and finer fractions in Zetasizer device. Nitrogen, carbon and phosphorus content were ranging from 0.91% ± 0.06 to 1.00% ± 0.05 for nitrogen and 10.76% ± 0.13 to 12.25% ± 1.58 for carbon. These results showed no difference between dry and wet sieving and no significant differences were found between carbon, nitrogen, content in different soil fractions which is according to literature and previous studies. However, phosphorus content showed significant differences among fractions ranging from 0.23% ± 0.00 in fraction 0.25- 0.053 mm. to 0.27% ± 0.00 in the coarsest fraction. We found an isoelectric point of 2.48 in the coarsest and 3.55 in the finest fraction, after oxidation isoelectric point was of 4.87 and 5.36 respectively. In accordance with other studies, high soil organic matter storage capacity of Andisols is a function of high surface area of non-crystalline constituents that are available for organic matter sorption, the ability of a soil for carbon sequestration could be related to the soil structure and pore features. Increasing evidence suggests that the long-term stability of soil organic matter (SOM) is dominated by organo-mineral interactions. However, the 2:1 phyllosilicate clays that provide much of the stabilization capacity in temperate soils are absent in tropical soils due to extensive weathering. Tropical soils instead contain an abundance of iron and aluminum short-range-order (SRO) minerals, capable of SOM stabilization through adsorption or coprecipitation due to their high specific surface area (SSA). This work characterizes the disproportionate contribution SRO minerals may lend to the SOM stabilization capacity of tropical soils. Surface (0-10 cm) soil samples were taken from 20 quantitative soil pits dug within the Luquillo Critical Zone Observatory in northeast Puerto Rico. Soils were stratified across granodiorite (DYS) and volcaniclastic (OX) parent materials. Four extraction procedures were used to isolate three different forms of Fe-C interactions: sodium pyrophosphate to isolate organo-metallic complexes, hydroxylamine and ammonium oxalate to isolate SRO Fe- and Al-hydroxides, and dithionitecitrate to isolate crystalline Fe-oxyhydroxides. Extracts were analyzed for dissolved organic C (DOC) and Fe and Al concentrations to estimate the amount of SOM associated with each Fe mineral type. Soils were subjected to SSA and solid-phase C analyses before and after extraction and muffling to determine the contribution of Fe mineral types to soil SSA. Preliminary results indicate that parent material is a significant driver of soil C storage, and soil C is unequally distributed among mineral fractions. Both Fe and C contents are significantly greater in OX-derived soils, which suggest that Fe-containing minerals are playing a direct role in C stability, and the highest C concentrations were observed in SRO extractions. The removal of these SRO minerals halved available SSA in both soil types. As such, SRO minerals may serve as critical drivers in tropical SOM stabilization, particularly compared to the bulk mineral matrix. University de la Frontera Università degli studi di Napoli Federico II 175 University of Pennsylvania University of Georgia Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Essential Soil Amendments for Soybean Production in Mozambique Canon Engoke, Stephen Boahen, Carlos Muananamuale, Irondino Saraiva Mechanisms of organic matter accumulation and plant nutrient acquisition in permafrost soils of Northwest Territory, Canada Kazumichi Fujii, Yojiro Matsuura, Akira Osawa International Institute of Tropical Agriculture (IITA) Forestry and Forest Products Research Institute Soybean utilization is expanding in Mozambique creating the challenge of increasing production by over 20,000 metric tons from the present 50,000 metric tons per year. Management interventions on soils resources both inorganic and organic are necessary to increase the current average of 1.3 tons ha-1 per unit area production among the smallholder farmers. A study was conducted to evaluate the response of soybean to phosphorus (P), nitrogen (N), inoculant and their interactions in four agro-ecologies across Mozambique. Two soybean genotypes (Storm and TGx 1904-6F) were established in 2010-2011, 20112012, 2012-2013 and 2013-2014 growing seasons using a split plot design with P rate (0 and 40 kg P ha 1) as main plot, inoculation application as subplots and N rate (0 and 40 kg N ha-1) as sub-sub plots with four replication per treatment. Data on yield and yield components were collected for a combined and individual location analysis using PROC GLM and MIXED in SAS 9.4 with season and location as random effects. The effect of location was more dominant than the other factors accounting for 25 to 89% of the variations in the measurable responses. Grain yield across all the four seasons was highest in Ruace (3640 kg ha-1) and lowest in Sussundenga (1975 kg ha -1). The growing conditions were favorable in 2013-2014 season yielding 2903 kg ha-1 and poor during the 20112012 season 2281 kg ha-1. Addition of P increased yield in all locations except in Sussundenga across the four seasons. Fate of permafrost soil receives increasing concern under changing climate. Permafrost thawing under warmer climate is predicted to accelerate organic matter decomposition, however, submerged condition is hypothesized to retard decomposition and nutrient cycles in plant-soil systems. To test this, we compared three sites in Northwest Territory, Canada; white spruce forest (WSF) on glaciofluvial sands, black spruce forest (BSF) and birch tundra (TND) on fluvial sediments. (1) Soil water dynamics, (2) SOC storage, (3) decomposition rates of lichen and moss litters and cellulose filter paper in soil, (4) concentrations of DOC, DON, and inorganic N in soil solution, and (5) plant N uptake (13C, 15N-glutamic acid, 15N-ammonium, 15Nnitrate) were monitored. (1) Flooding events were observed following spring snowmelt and summer permafrost thawing in relatively low sites (BSF and TND). The feature of redox cycles was recorded by accumulation of oxalate-extractable Fe oxides (Feo). In WSF soil, deep thawing enhanced water percolation and aeration. (2) SOC storage in BSF and TND were significantly greater than in WSF. Positive correlation between SOC and Feo suggested that cold and anaerobic condition increased SOC storage. (3) Mass losses of cellulose were greater in WSF than in BSF and TND, while those of lichen and moss litters were consistently low. (4) DOC production was greater in BSF and TND due to limited mineralization. (5) DON was abundant at all sites, but inorganic N was abundant only in TND. Birch preferentially absorbed inorganic N, while white spruce and black spruce could also utilize amino acid-N. Submerged condition as well as cold climate is responsible for SOC accumulation. Accumulation of sparingly-decomposable lichen and moss debris in BSF could limit deep thawing and increase SOC storage. Variation in soil moisture and N acquisition strategies can drive plant-soil feedbacks. Water dynamics need to be considered to predict permafrost ecosystem responses to changing climate. 176 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Investigation of the relationship between total soil organic carbon (SOC) and mineralogical and physical attributes of an Amazonian Ferralsol-Podzol soil system, Brazil Ishida1, Montes2, Débora Ayumi Célia Regina Osvaldo José Ribeiro Pereira2, Aldolpho José Melfi3, Yves Lucas4 1 NUPEGEL, IEE, Universidade de São Paulo NUPEGEL, CENA, Universidade de São Paulo 3 NUPEGEL, IEE, ESALQ, Universidade de São Paulo 4 NUPEGEL, PROTEE, Université du Toulon 2 Several researches have already investigated the relationship between soil organic matter (SOM) and mineralogical and physical soil attributes. In some soils (eg.: Podzols) the fine soil textural fraction is the major condition to form deep horizons rich in organic matter (Bh horizons). The objective of this study was to investigate the role of soil mineralogical and physical attributes to form the Bh horizons, based on the correlation of these attributes with the total soil organic carbon (SOC). Hence, we investigated two soil profiles in a Ferralsol-Podzol soil system. The mineralogy of profiles is quite similar but with different amounts of quartz, kaolinite and gibbsite and different soil porosity fabric. In Podzol, quartz is prevalent in the horizons A and E, which presenting macro and mesopores. In the silty-clay Bh horizon, kaolinite and gibbsite are prevalent with relictual pores. In Ferralsol we observed a progressive increase in kaolinite and gibbsite and a decrease in quartz from the topsoil to the base of the soil profile and the relicutal pores were prevalent in the profile. In Podzol the obtained Pearson coefficients are above 0.6 between SOC content and the both variables gibbsite and clay textural fraction. The content of quartz and sand is related with SOC (above 0.65) just to Ferralsol. The pedogenetic process in Podzol allows the translocation of SOC through A and E horizons. The minerals from the silty-clay fraction and the soil relictual porosity lead to the accumulation of SOC in Bh horizons. The progressive increase of the concentration of soil minerals in the silty-clay fraction of Podzol and the maintenance of relicutal soil pores are the main reasons for a gradual increase in SOC content from the topsoil to the base profile. 177 Physical protection of cutin and suberin in soil via organo-mineral associations Lisa Lin, Myrna Simpson University of Toronto Soil organic matter (SOM) is essential for maintaining long-term agricultural sustainability and plays a major role in the biogeochemical cycling of carbon and nitrogen. Cutin and suberin are shoot- and root-derived biopolymers that are hypothesized to be recalcitrant components of SOM because of their long residence time in soil. Two proposed mechanisms that preserve these biopolymers are chemical recalcitrance and mineral protection. Sorption studies have shown that cutin-derived compounds can preferentially sorb onto clay mineral surfaces, suggesting that organo-mineral interactions may be an important mechanism for stabilizing SOM. To examine the role of mineral protection, we used hydrofluoric acid (HF) demineralization prior to cutin and suberin biomarker extractions to assess the extent of mineral protection of cutin and suberin. Base hydrolysis was performed to extract the biomarkers from four Canadian soils with varying land use (grassland, agricultural, forest). These soils varied in organic carbon content and mineralogy. Results show that 83-98% of the suberin biomarkers and 81-96% of the cutin biomarkers were protected by the soil mineral phase. The percentage of protected biomarkers is largely related to the type of clay minerals in the soils because soils that contain montmorillonite exhibited a greater degree of protection. Protection of cutin and suberin may have also occurred via SOM-SOM interactions in soils with higher amounts of SOM. The suberin/cutin ratios for the grassland and agricultural soils increased after the HF treatment, indicating that more suberin biomarkers were mineral-bound than cutin biomarkers. The suberin/cutin ratio for the forest soil was 1.0 before and after the HF treatment, demonstrating that there were equal proportions of mineral-protected suberin and cutin biomarkers. Therefore, in addition to the widely accepted hypothesis of chemical recalcitrance, we found that cutin and suberin can also be protected from microbial degradation and biogeochemical cycling via interactions with clay mineral surfaces. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluation of clay mineral and suberin and cutin protection of lignin in soil Effect of aluminum on available carbon from an Andic and Metamorphic temperate rain forest soil Olivia Lun, Myrna Simpson University of Toronto Soil organic matter (SOM) contains around 1580 gigatons (Gt) of carbon and is one of the largest global reservoirs of carbon. Despite its key role in carbon sequestration, the fundamental factors governing SOM stabilization remain unclear. Organo-mineral associations contribute greatly to OM stabilization mechanisms. Recent studies have demonstrated that organic matter may be protected from degradation through sorptive interactions with clay mineral surfaces but such associations are rarely examined at the molecular-level. While there is active debate on the chemical recalcitrance of lignin, cutin and suberin, studies have proposed that lignin may protect cutin from degradation in spruce litter, which triggered our investigation into the preservation patterns of cutin and suberin in soils. Hydrofluoric acid (HF) demineralization was used to evaluate the extent of clay mineral protection of lignin-derived phenols. Base hydrolysis was used to isolate suberin and cutin monomers in grassland, agricultural and forest soils with varying organic carbon content and clay mineralogy before and after demineralization. Gas chromatography-mass spectrometry was used to analyze lignin-derived phenols released from soil using CuO oxidation before and after cutin and suberin extraction and demineralization. The percentage of mineral-protected lignin monomers ranged from 3100%, where greater protection was observed in the grassland soils which contain montmorillonite. Only the agricultural soil exhibited a lower degree of mineral protection but more suberin and cutin protection of lignin. This may be due to the relatively lower clay content and lack of high surface area smectite minerals in this sample. These results suggest that mineral protection is a major protection mechanism of lignin, while suberin and cutin protection plays a secondary role and is dependent upon soil properties. The preservation patterns of cutin, suberin and lignin should be closely examined to understand their correlation with organo-mineral associations and how they collectively contribute to OM stabilization processes. 178 Carolina Merino, Francisco Matus, Graciela Palma, Universidad de la Frontera, Ciencias Quimicas y Recursos Naturales Soluble or colloidal organic matter that would otherwise be available for microbial assimilation and how it interacts with soil minerals has not been fully established. The role of aluminum, (Al) on carbon (C) sequestration and its effects on available C and biodegradation was evaluated on soil organic matter and water extractable organic matter (WEOM). Samples were obtained from Andic and Metamorphic soils (5-15 cm) belonging to old growth temperate rain forests in southern hemisphere. WEOM and mineral soils horizons were incubated with increasing dosage of Al AlCl3 at environmentally relevant concentrations: 0, 0.2, 0.4, 2, 4 and 8 mg L-1 (or mg kg-1). The carbon mineralization of WEOM from C-CO2 collection after 3 days of incubation experiment showed no significant differences compared with the control without addition. Potentially toxic Al3+ were observed over a molar Al:C ratio > 0.12 after 15 days of incubation. In contrast, Al addition in mineral soils horizons presented a monotonic decreased of mineralization from Al:C ratio > 0.17. Increasing Al concentration left Al-humus formation as indicated by ATR-FTIR spectra in mineral soils. Our data supported the hypothesis that organic C decay is not affected by potentially toxic Al 3+, but by availability C as previously established. We conclude that the Al:C ratio is a crucial pedogenic indicator of C transformation particularly on the availability of organic C in acidic soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The effect of clay mineral composition on microbial residues in artificial soils as reflected by amino sugar content Soil microaggregate formation as revealed by the bulk and spatial elemental composition Geertje Pronk1, Katja Heister2, Ingrid KögelKnabner2 Nina Siebers1, Hamada Abdelrahman2, Wulf Amelung1 1 1 2 2 The binding of microbial residues on mineral surfaces is an important process in the formation and stabilization of soil organic matter (SOM). However, the effect of mineral composition on microbial activity and thereby SOM development is still not well understood. We studied the effect of mineral composition on SOM development in artificial soils composed of four different mixtures containing illite, montmorillonite, ferrihydrite and charcoal. In addition, silt- and sandsized quartz was added to provide texture, sterilized manure was used as OM source and the mixtures were inoculated with a microbial community extracted from a natural soil. The mixtures were incubated in the dark for 3 to 18 months, and amino sugar and muramic acid content in the bulk soil and < 20 µm fraction were determined. Amino sugar content was generally low and changed only slightly in the < 20 µm fraction with incubation time, indicating that microbial residues in the form of amino sugars did not preferentially accumulate with time. The montmorillonite containing mixture had a higher galactosamine and glucosamine content than the other mixtures, pointing to higher fungal residue formation. This effect was most pronounced for the bulk soil, indicating that fungal residues accumulated on coarse particulate OM and macroaggregates rather than in the fine fraction. Thus, it seems that the effect of minerals on amino sugar content was due mainly to changing local environmental conditions and thereby microbial community properties, and not due to direct interaction of amino sugars with mineral surfaces. This highlights the importance of considering the entire soil system in order to gain understanding of the interaction between microbes, minerals and SOM. Within the soil aggregate system, microaggregates (< 250 µm) are supposed to be of primary importance, as they are strongly linked with essentially all processes controlling interaction, transport, and turnover of soil constituents. They are composed of mineral and organic components arranged in a heterogeneous but rather unknown pattern. We want to elucidate the bulk and spatial elemental composition of microaggregates and how it differs in soil of different land-use. We hypothesize that from the bulk and spatial elemental composition the aggregation mechanisms of microaggregates can be deduced to some extent. To test this, we obtained microaggregates (< 250 µm) by dry sieving from three different soils (permanent grassland, arable, forest). These soils were disintegrated using ultrasound in suspension. After freeze-drying, the particle-size distribution was determined using electron microscopy (EM) and a particle-size analyzer. First results of particle-size distribution analysis revealed that microaggregates of grassland was smallest (volume distribution (Dv) 90% was 56 µm), whereas particles in the arable and the forest soil was larger (Dv90% was 71 and 60 µm, respectively). Similar trends were observed for Dv50% and Dv10%. After disaggregation, the order of increasing particle-size fraction was the same; however, microaggregates sizes of the grassland decreased in average about 70%, whereas for the arable and the forest soil it was only about 24% (Dv90% and Dv50%), hinting at a lower stability of microaggregates in grassland. C/N analysis revealed lowest ratios for the grassland, which is surprising as this hints to a slower turnover of Corg compared to the other soil and, thus, higher aggregate stability. However, EM and elemental composition analyses revealed a lower Fe-content compared to the other soils and also visual analysis showed a looser connection of microaggregate components. Further analysis using elemental mapping should reveal the spatial elemental distribution of components allowing drawbacks for aggregation mechanisms. University of Waterloo, Earth and Environmental Sciences Technische Universität München 179 Institute of Bio- and Geosciences, IBG-3 Agrosphere Cairo University, Agriculture Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A survey of Glomalin Related Soil Protein in relation to land-use and soil properties Siobhan Staunton1, Priscila Jorge-Araujo1, Paula T. Matumoto-Pintro2, Hervé Quiquampoix1, Nicolas Saby1, Claudy Jolivet1, Dominique Arrouays1 1 INRA, UMR Eco&Sols Universidade Estadual de Maringá 2 Glomalin, the operationally defined soil protein produced by Glomus fungi, confers physical stability to soil and contributes to stable stocks of carbon and nitrogen. The protein is assayed using the nonspecific colorimetric Bradford assay or, more rarely using an immunochemical ELISA test. Glomalin related soil protein (GRSP) is increasingly used as a marker of fungal activity. However there is increasing debate as to the precise nature of the protein detected. The aim of this study was to compare the GRSP to land-use and soil properties in order to elucidate its origin and persistence. This is the first large scale screening of GRSP. We selected 200 topsoils from the collection sampled in the framework of the French soil monitoring network. Detailed composition of the soils and the corresponding land-use is known for all the samples. GRSP followed a similar trend to soil organic carbon content (SOC) with no strong correlations with other soil properties. Data mining using the Cubist algorithm identified total nitrogen, non-complexed organic carbon followed by organic carbon content to be important determinants of GRSP whereas other parameters had less importance and land occupation ranking very low, less than 5%. The land-use effect is largely accounted for in carbon content and degree of complexation. These observations do not support the hypotheses that GRSP is stabilized by association with clay minerals. The absence of a correlation with land-use or fertilization suggests that GRSP may not be completely of fungal origin and may include non-protein compounds. 180 Impacts of agricultural management on soil organic carbon changes in Danish mineral soils Arezoo Taghizadeh-Toosi, Jørgen Eivind Olesen Aarhus University Soil organic matter (SOM) accounts for a significant carbon (C) reservoir, and its rate of turnover is important for predicting the C sequestration potential of soils subject to changes in land-use and climate. The C-TOOL model is a three-pool linked soil organic carbon (SOC) model in well-drained mineral soils under agricultural land management. The C-TOOL model was developed to simulate SOC storage on medium- to long-term trends in the whole soil profile (0100 cm). C-TOOL was parameterized using SOC and radiocarbon data from selected long-term field treatments in North West Europe. However, less data were available for evaluation of subsoil C (25-100 cm) from the long-term experimental trials. In Denmark a national 7 × 7 km grid net was established in 1986 for soil C monitoring down to 100 cm depth. The results of SOC indicate a small annual loss of 0.2 t C ha -1 from the 0-100 cm soil layer between 1986 and 2009. Across the period 1986 to 2009, there was clear tendency for increasing SOC on the sandy soils and reductions on the loamy soils. This effect is linked to land use, since grasslands and dairy farms are more abundant in the western parts of Denmark, where most of the sandy soils are located. The results and the data from soil monitoring were used to validate the C-TOOL modelling approach. Future work will focus on further evaluating effects on subsoil C as well as improving the estimation of C inputs, particularly root C input from various crops at different soil depth. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil chemicals attributes influenced by the use of spontaneous species as green manure Stability of soil nanoparticles as affected by natural organic matter in electrolyte solutions Marcos Antonio Vieira Batista, José Nilson Oliveira Filho, Francisco Airdesson Lima do Nascimento, Cristian Franca Santos, Ivam Isidório de Almeida, Luiz Romário Uchôa Huiming Chen, Xinyu Zhu, Jianming Xu* Instituto Federal de Educação Ciência e Tecnologia do Ceará-IFCE The growing consumer demand for food safety has increased the demand for healthy food, free from contamination by chemicals, generating, thus, the need for adoption of an alternative technique production to minimize or to eliminate the use of mineral fertilizers. Among these techniques is green manure. This is the incorporation into the soil of plants with high biomass production, rich in nutrients, which can improve the soil, physically, chemically and biologically, and provide conservation or increased fertility. The northeastern Caatinga has a great diversity of species, and some as roostertree (Calatropis procera) can constitute an alternative for use as green manure for its increased availability and easy way to get it. Among the effects of green manure there is the increase organic matter, greater availability of nutrients, cation exchange capacity increase, recyclability and mobilization of nutrients. These effects are variable, depending on the used species, the management given to biomass, the residence time of waste in the soil, local conditions and the interaction between these factors. Roostertree (Calotropis procera) is a spontaneous plant vegetation of the Caatinga biome. In the semi-arid northeastern Brazil has been used as green manure in different cultures. The objective of this study was to evaluate soil chemicals attributes influenced by the use of roostertree as green manure. This study was carried out from July to October 2014 in Iguatu, Ceará state, Brazil. The experimental design was a randomized complete block with four replications. The treatments were different quantities of Calotropis procera incorporated into the soil (0.0; 6.0; 12; 18; and 24 t ha1 on dry mass). The chemical characteristics evaluated in soil were: carbon, organic matter, sulfur phosphorus and potassium. The quantities studied did not differ in the levels of phosphorus and potassium in the soil. There was a linear increase in the levels of carbon; organic matter and sulfur. The increase was of 112; 145 and 252 percent, respectively. 181 Institute of Soil and Water Resources and Environmental Science, Zhejiang University Natural nanoparticles are ubiquitous in soils, and their quantity and stability play important roles in the fate, transport, and bioavailability of both nutrients and contaminants in soil and water. In this study, natural organic matter (NOM) from three different sources was added to a suspension of soil nanoparticles (SNPs) to determine the effects of NOM on the stability of SNPs. The SNPs were extracted from four typical soils (HN, Oxisol; JX, Ultisol; LN, Inceptisol and JL, Inceptisol) from different regions of China. The critical coagulation concentration, one of the most important indicators of the stability of colloidal suspensions in electrolyte solutions, was determined. The critical coagulation concentration results showed that the presence of NOM enhanced the stability of SNPs, which varied with the properties of NOM, electrolytes and SNPs. Since a NOM coating increased the negative charges on the surface of SNPs, the electrostatic force had a greater effect on the stability of SNPs than the van der Waals force, which stabilized the SNPs. The properties of NOM (such as aromaticity) were closely related to the extent of the stability change of the SNPs. The influence of NOM on the stability of SNPs was more apparent in electrolytes with a monovalent cation (Na +) compared to those with a divalent (Ca2+) or trivalent cation (La3+). Meanwhile, NOM proportionately increased the stability of less stable SNPs. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Interactions between oppositely charged surfaces in variable charge soils and the electrochemical properties at interfaces between them Renkou Xu, Jiuyu Li, Zhineng Hong, Zhaodong Liu, Zhongyi Li State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science There are various charged surfaces in variable charge soils. Fe and Al oxides normally carry positive charge on their surfaces. Phyllosilicate, organic matter, bacteria and plant roots mainly carry negative charge. The interactions between oppositely charged surfaces affect electrochemical properties at interfaces between them and subsequently the chemical behaviors of nutrients and heavy metals and uptake of these elements by plant roots. Our results indicated that overlapping of diffuse layers (ODL) of electric double layers on positively charged Fe/Al oxides and negatively charged phyllosilicate occurs in variable charge soils due to strong leaching. ODL on oppositely charged particles led to decrease in effective charge at interface between them, and the process was reversible and decreased with increase in ionic strength of soil solution. ODL on oppositely charged particles was responsible for the salt adsorption and inhibition of Fe/Al oxides on natural acidification in variable charge soils. Bacteria adhesion on Fe/Al oxides and the soils was mainly affected by their surface charges and the more charge on their surfaces led to the greater adhesion of bacteria. More positive charge on Al oxides led to much greater adhesion capacity for bacteria than Fe oxides. Bacteria adhesion decreased positive charge and increased negative charge on Fe/Al oxides and the soils. A streaming potential method was developed to measure zeta potential of plant roots and to characterize the interaction of Fe/Al oxides and soils with plant roots. More works need to be conducted in future. 182 Differential adsorption of phenolic- and nitrogenous compounds on mineral phases Anna Zavarzina1, Vladimir Demin1, Natalia Zagoskina2 1 Moscow State University, Soil Science Moscow State University, Plant Physiology 2 Plant-derived phenolic compounds are main structural precursors of humic substances, however, our knowledge on their reactivity in soils is scarce. We have studied adsorption capabilities of lignin-derived phenolic acids (PA) on mineral phases and oxidation potential of PA in the presence of fungal laccase. Ferulic, caffeic, gallic, vanillic, hydroxybenzoic acids as well as tyrosine and tryptophane were used. Kaolinite (kaol), montmorillonite (mntm), illite and kaolinite coated by Al(OH)x served as solid phases. Phenolic acids (50-1000 g/ml) dissolved in 10 mM Na-acetate buffer (pH 4.5) were added to the minerals individually or in a mixture. Reactions were performed at 22°C within 1 h. Compounds adsorbed were quantified by reversed phase HPLC. Interactions of individual acids with fungal laccase were perfomed at pH 4.5 within 24 h. It was found that individual phenolic acids were adsorbed on the minerals in similar amounts, while differential adsorption was observed in mixtures. Adsorption order was as following: tyrosine < tryptophane < vanillic < hydroxybenzoic < ferulic < caffeic < gallic acids. The sequestration of PA is due to their own reactivities because the type of mineral phase did not affect the order of adsorption. Amounts of PA adsorbed per g of mineral increased in the order kaol<mntm<kaol-Al(OH)x<illite, corresponding to the increase in mineral surface area. The adsorption density (mmol PA per m2) was the highest on kaolinite and positively charged complex of kaolinite with Al(OH)x. The oxidation potential of PA in presence of laccase followed the order HBA<CAF<GAL. The results show that differences in sorption and oxidation capabilities of plant-derived phenolics influence the composition of stable organic matter in soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Interaction of lichen laccases and soluble phenolics with minerals: implications for humification Anna Zavarzina1, A.A. Lisov2, N.V. Zagoskina3, A.A. Zavarzin4 1 Moscow State University, Soil Science Institute of Biochemistry and Physiology of Microorganisms 3 Moscow State University, Plant Physiology 4 St-Petersburg State University, Biology and Soil Sciences 2 Lichens comprise the dominant soil cover on about 6% of land surface, mainly in polar zones, high mountain elevations and oligotrophic forests. Lichens are known as agents of rock weathering, alternatively, by overgrowing their mineral substrate they stabilize it from erosion. Little is known about the role of lichens in the formation of stable soil organic matter. Our earlier work has shown that lichens, especially representatives of the order Peltigerales, contain laccases and tyrosinases (Zavarzina and Zavarzin, 2006). We have also found occurrence of water-soluble phenolic metabolites in lichens, representing conjugates of vanillic, hydroxybenzoic and protocatechuic acids (Zagoskina et al 2013). We hypothesize that phenoloxidases and phenolic conjugates, washed-out of the thalli, can interact with soil mineral constituents and participate in heterophase synthesis of humic substances (Zavarzina, 2011). This will result in long-time preservation of lichen C in polymeric organo-mineral complexes. Here we have studied 1) adsorption of purified laccase from soil stabilizing lichen Solorina crocea on pure clays and on soil A horizons; 2) oxidation potential of soluble phenolics from Peltigera aphthosa, Solorina crocea, Cetraria islandica and Cladonia stellaris in presence of laccase; 3) adsorption of lichen phenolics on clays and soil. It was found, that lichen-derived laccase was quickly adsorbed by clays and soil and retained 2050% of its initial activity. Therefore, laccase can act as heterogeneous biocatalyst in humification reactions in soil. Phenolic conjugates in water extracts from four lichens under study showed similar oxidation potentials but quite different adsorption capabilities. Overall, our results have shown potential of lichen-derived organic matter to be stabilized in soils and participate in the formation of humic matter. 183 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S5: Analytical and Methodological Advances in Soil Study 184 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Prediction of soil phosphorus forms using visible near infrared reflectance spectroscopy Dalel Abdi1, Barbara Cade-Menun2, Noura Ziadi1, Gaëtan Tremblay1, Léon-Étienne Parent3 1 Soil and Crops Research and Development Centre, AAFC Semiarid Prairie Agricultural Research Centre, AAFC 3 Université Laval, Soils and Agri-Food Engineering 2 Visible near infrared reflectance spectroscopy (VNIRS) is a rapid, inexpensive, and accurate analytical technique for a wide variety of materials and its use is increasing in soil science. The aim of this study was to examine the potential of VNIRS to estimate soil total P (TP), total inorganic P (IP), total organic P (OP), and P as extracted by two methods [Mehlich 3 (PM3) and Olsen (Pols)]. Soil samples (n = 360) were taken from an experimental site near Indian Head, SK, Canada, from short-term (8 yr, n = 180) and long-term (31 yr, n = 180) conservation tillage plots of a pea and spring wheat rotation field receiving five P fertilizer rates annually. Samples were collected at three soil depths (0-7.5, 7.5-15, and 15-30 cm). Calibration VNIRS equations were developed using 80% of the soil samples and the partial least squares regression while the remaining 20% of samples were used for validation. The predictive ability of VNIRS was evaluated using the coefficient of determination of validation (R2) and the ratio of standard error of prediction to standard deviation (RPD). Predictions were considered moderately successful for IP and OP (0.80 < R2 < 0.90 and 2.25 < RPD < 3.00), and moderately useful for PM3 and Pols (0.70 < R2 < 0.80 and 1.75 < RPD < 2.25), but less reliable for TP (R2 < 0.70, RPD < 1.75). This study showed that VNIRS has the potential as a non-destructive and cost-efficient tool for rapid determination of IP, OP, PM3, and Pols. 185 Towards an understanding of precipitation dissolution mechanisms of inorganic P in calcareous soils using mineral stability diagrams Yuki Audette, Leslie Evans, Ivan O’Halloran, Ralph Martin, Paul Voroney University of Guelph Phosphorus (P) is chemically reactive, binding strongly to soil mineral surfaces and forming relatively insoluble compounds, both of which may limit its availability of P for plants. In calcareous soils, the fate of P is controlled mainly by interactions with surfaces of clay and oxide minerals, and precipitation as secondary calcium phosphates. Using acid dissociation constants, formation constants for P complexes, and solubility constants for the major soil P minerals, it is possible to predict which minerals precipitate under specific soil chemistries. In order to do so, all constants need to be re-calculated to the ionic strength of the soil solution (when I > 0.012 M), and include appropriate elements forming P complexes in the soil solution. In this study, a computer model was developed to predict the proportions of the major P complexes and the stability of the major Ca- and Mg-P minerals as a function of soil pH. The model predicted which P complexes and mineral P precipitates were predominant and how stable they were under specific soil chemistries. The study also showed that excluding the effects of ionic strength and elements forming P complexes in soil solution gave erroneous predictions of the stability of P minerals. Mineral P stability and P complex diagrams are useful predictive tools, especially when selecting an appropriate extractant for targeting P forms and predicting the effects of soil amendments on soil P chemistry under specific soil conditions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Investigation of Soil Legacy Phosphorus Transformation in Long-Term Agricultural Fields Using Sequential Fractionation, P Kedge XANES and Solution P-NMR Spectroscopy Barbara Cade-Menun1, Jin Liu1, Yongfeng Hu2, Jianjun Yang3, Dalel Abdi Identifying drought susceptible areas by using GIS: meteorological and soil properties approaches Hector Estrada-Medina1, Juan HernándezHernández2, Mariela Castilla-Martinez1, Mariana López-Diaz1, Andrés Morales-Guadarrama1, Oscar Álvarez-Rivera1 1 1 2 2 Semiarid Prairie Agricultural Research Centre, AAFC University of Saskatchewan, Canadian Light Source 3 University of Delaware, Plant and Soil Sciences 4 Université Laval, Soils and Agri-Food Engineering Understanding legacy phosphorus (P) build-up and draw-down from long-term fertilization is essential for effective P management. Using replicated plots from Saskatchewan, Canada, with P fertilization from 19671995 followed by either P fertilization or P cessation (1995-2010), soil P was characterized in surface and subsurface layers using sequential fractionation, P Kedge X-ray absorption near-edge structure (XANES) and solution 31P nuclear magnetic resonance (P-NMR) spectroscopy. Legacy P from a 28-yr build-up was sufficient for 15 years of wheat cultivation, resulting in no significant differences in crop yield in 2010. In surface soils, soil test (Olsen) P decreased significantly in unfertilized plots compared with 1995, which was reflected in declining aluminum (hydr)oxide-associated inorganic P by fractionation and XANES. Furthermore, XANES analysis revealed a decrease of calciumassociated P in 2010-unfertilized soils at both depths and an increase of Fe (hydr)oxides-associated P in the 2010-fertilized and -unfertilized surface soils relative to the 1995 soils. Increased total organic P and orthophosphate diesters by P-NMR and accumulated inositol hexaphosphate by XANES were observed in surface soils with P fertilization cessation. In subsurface soils, few legacy P transformations were detected. These results provide important information about legacy P to improve agricultural sustainability while mitigating water quality deterioration. 186 Universidad Autónoma de Yucatán (UADY) Servicio Geológico Mexicano (SGM) Agricultural drought (AD) starts when soil water shortage has negative impacts on crops and occurs at any stage of plant development. AD is dependent of meteorological conditions, crop characteristics and soil properties. Evapotranspiration (ET) is often used to predict AD; however, it is very difficult because calculation of ET involves several variables not available everywhere. In this study we used maps of temperature and precipitation data series from 19822013 from 85 meteorological stations of the state of Yucatan as well as soil property maps to identify dry areas susceptible to AD. To elaborate the maps the raw data from weather stations and soil lab analyses where depurated and then interpolated by using the GS+ software, final maps were elaborated in ArcGIS. We overlapped annual precipitation, mean temperature and extreme temperature maps to identify susceptible AD areas (i.e. areas with precipitation below and temperature above the historical means and, extreme temperatures above average). We also overlapped depth, organic carbon and clay content soil maps to identify predisposed soils to AD (i.e. soils with depth, organic carbon and clay content below the average). Meteorological approach showed a small region located in the north-central of the state as the most vulnerable to AD, where precipitation is below the average of 1058 mm and the extreme temperature above 40°C. Soil properties approach showed small dispersed susceptible areas to AD in the south, east and west of the state. We conclude that although the susceptible areas to AD identified were small, there are large areas where soil depth, organic carbon and clay content are low enough to make these areas susceptible to AD, in a particular year where precipitation decreases and/or extreme temperatures increases significantly with respect to the average. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Comparison between mid-IR (ATR) and nearIR (DRIFT): Spectroscopy as a means of determining ten properties of soil employing partial least squares analysis Qianjun Gan, Ashraf Ismail McGill University, Food Science Prescription or precision farming provides precise data of soil physical, chemical, and biological properties, and therefore giving a better farm management guidance to the farmers to enable them to proceed more efficient, more profitable, and more environmental-friendly farming activities. This requires the development of a more powerful, easy assessed, efficient technique with higher accurate result for the precision farming. This project aims at using Fourier Transform Infrared Spectroscopy (FTIR) equipped with Partial Least Squared (PLS) regression technique to establish Midinfrared (MIR-PLS) and Near-infrared (NIR-PLS) calibration models of ten soil attributes, Total Organic Carbon (TOC); Total Nitrogen (TN); Carbon-toNitrogen ratio (C/N); Ammonium (NH4+); Nitrate (NO3-); Sand; Silt; Clay; N uptake; and Yield on (n=282) soils. These ten attributes are closely related to soil quality. Also, a decision of the method which is more appropriate in soil quality monitoring, considering the accuracy and reliability of the prediction performance of the models should be made. According to the preliminary results, both MIR-PLS and NIR-PLS models showed promising prediction performance to soil attributes, especially those of TOC (Rcv-MIR2 0.83 RPDMIR 1.81; Rcv-NIR2 0.80 RPDNIR 1.66), TN(Rcv-MIR2 0.83 RPDMIR 1.76; RcvNIR2 0.76 RPDNIR 1.49), and clay content(Rcv-MIR2 0.89 RPDMIR 2.12; Rcv-NIR2 0.87 RPDNIR 1.84 ). MIR-PLS had better performances than those of NIRPLS, with 30-180% Rcv2 and 15-120% RPD increment over the ten soil properties. 187 Développement et validation d’une approche d’évaluation en laboratoire de la santé globale des sols adaptée au marché agricole Mélanie Gauthier, Karin Arseneault, Liva Checkmahomed, Christiane Bochud, Michel Champagne Agro-Enviro-Lab L’évaluation de la santé d’un sol a toujours été basée sur une série de mesures chimiques qui considère le pH, la matière organique et les éléments nutritifs. Cependant, pour assurer la productivité et la conservation des sols à long terme, les propriétés physique et biologique doivent être considérées. Pour ce faire, il faut pouvoir tabler sur des indicateurs fiables et abordables qui illustrent les impacts des pratiques de gestion agricoles, de même que la dégradation et/ou l’amélioration de la santé des sols. Basée sur une revue de littérature exhaustive et une collaboration avec l’université Cornell, 11 indicateurs de la santé des sols ont été sélectionnés, développés et validés dans nos laboratoires. En 2013 et 2014, 87 échantillons de sol ont été prélevés à partir de champs représentant les trois groupes texturaux. 37 échantillons ont été analysés en triplicata afin de valider les indicateurs suivants: la stabilité et la proportion des agrégats, l’azote potentiellement minéralisable et le carbone actif. Pour chaque indicateur, un échantillon standard a été analysé 10 fois afin de mesurer la répétabilité et la réplicabilité du procédé expérimental. De plus, un échantillon a été analysé par les laboratoires de l’Université Cornell afin de mesurer la justesse. À cela s’ajoute l’évaluation de la santé des sols de 800 champs à travers le Québec, afin de constituer une base de données représentative permettant d’associer un classement aux résultats de chaque indicateur et ainsi en faciliter leur interprétation. Les résultats de cette démarche menée en 2014, nous permettent d’offrir commercialement une évaluation de nature quantitative de la santé globale des sols qui est conforme aux critères d’accréditation d’une méthode d’analyse des sols. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Quantitative carbon speciation in soils using soft X-ray spectroscopy In situ quantification of canola root biomass in relation to canola growth and tolerance to climate stress in Québec Adam Gillespie1, James J. Dynes1, Tom Z. Regier1, Derek Peak2 Mitalie Makhani1, Joann Whalen1, Bao-Luo Ma2 1 1 2 2 Determining the chemical speciation of carbon in soils is important for understanding the role of organic matter in biological stability, contamination mobility and nutrient cycling. Soft X-ray absorption spectroscopy (XAS) probes the local bonding environment light elements in whole soils and requires little preparation. Bulk XAS techniques permit for high throughput, the study of whole soils and high sampling density. Technical challenges, particularly at the carbon Kedge, which have limited its extensive application of to environmental samples have now been largely solved. Presented here is a study covering carbon quantitation methods using reference materials and soils. Climate stressors such as high temperature stress, greatly impact canola production. In order to optimize canola production against climate stress, more research on root systems is needed. A well-developed root system in canola is expected to help the crop with better tolerance to temperature stress since root biomass can improve canola’s thermotolerance by allowing plants to transpire water as an internal cooling process. The objectives of this study are to (i) examine the relationship between canola root growth and its aboveground growth, and (ii) determine how root growth can improve canola’s thermotolerance. The framework focuses on fine roots, since canola contains a very fine, dense root network. However, conventional methods of quantifying root biomass are highly destructive, time and labor intensive and are inadequate in capturing fine roots. The root derived carbon method, based on 13CO2 enrichment of plants, will be used to precisely estimate root biomass of canola. This method will be tested in growth chamber studies and in situ, to evaluate root biomass dynamics of canola under various nutrient management practices, soil fertility status and also during high temperature stress with interactive effects of other abiotic stressors such as drought stress, common in Québec. Canola varieties will be tested for their adaptive capacity to these stressors based on root biomass production. Relationships between root biomass and seed and pod production will be evaluated using robust statistical and crop growth models. Quantifying root biomass dynamics in relation to abiotic stressors and their interactive effects will be important for plant breeders developing tolerant canola varieties and for agronomists, since these considerations are needed to adapt and sustain canola production in Québec to a changing climate. University of Saskatchewan, Canadian Light Source Inc. University of Saskatchewan, Soil Science 188 McGill University, Natural Resource Sciences Eastern Cereal and Oilseed Research Centre, AAFC Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Methodological framework to predict soil hydraulic properties from a tomodensitometric analysis Characterization of organo-mineral associations from tropical soil profiles using solid-state 13C NMR and thermal analysis Yann Périard1, Silvio José Gumiere1, Alain N. Rousseau2, Jean Caron1 Alain Plante1, Maddie Stone1, William Hockaday2 1 1 2 2 Knowledge about soil hydraulics properties such as water retention characteristic and the hydraulic conductivity curves are fundamental for water flow and contaminant transport modeling in the vadose zone. However, the characterization of these properties is very time-consuming and requires many sample manipulations. Tomographic imagery provides a costeffective and rapid methodological approach to characterize a number of soil hydraulic properties. Indeed the use of CT-scan allows the characterization of the porous media at the pores scale, giving information about the pore size distribution and the pore network connectivity itself. However, the use of micro scanning has limits on sample size making inappropriate to study a representative volume of a specific process described by a macroscopic model. Therefore, the main objective of this work is to propose a framework to predict soil hydraulic properties from the combination of particle size distribution and X-ray tomography of a porous media. A sandy soil sample was analyzed with a medical CT scan at a resolution of 100 µm for a voxel. Also the water retention curve and the hydraulic conductivity were obtained by instantaneous profile method for the sorption and desorption curves. Moreover, the soil particle size distribution was obtained within a LA950v2 Laser Particle Size Analyzer (Horiba). The soil hydraulic properties obtained from the framework application showed a very good agreement with those obtained with current soil physics measurements. The development of this novel framework has provided an opportunity to study the spatiotemporal variability of soil hydraulic properties of a porous media at the soil profile scale (1 m of length) under experimental conditions inducing hydroconsolidation and particle transport. Tropical forest soils store large quantities of carbon (C) as soil organic matter (SOM), but the composition of tropical SOM remains poorly characterized, in part due to the analytical challenges associated high iron and low C concentrations. In this study, we used solid-state 13C nuclear magnetic resonance (NMR) spectroscopy to explore patterns in SOM chemistry across two soil and forest types and with depth at the Luquillo Critical Zone Observatory (LCZO) in northeast Puerto Rico. Prior to 13C NMR, soils were repeatedly demineralized with hydrofluoric acid (HF) to remove paramagnetic compounds and concentrate organic matter. Given the scant information on tropical subsoil OM, we sought to evaluate the effect of HF acid treatments on tropical subsoil SOM using simultaneous thermal analyses (TG-DSC-EGA). HF treatments effectively enriched sample C and removed paramagnetic compounds, allowing us to obtain high-quality NMR spectra for lowC subsoils. C:N ratios before and after HF treatment were nearly identical (mean = 16.6 ± 0.8), suggesting that the SOM pool was not substantially fractionated. Thermal analyses confirmed loss of a substantial fraction of the soil mineral matrix, however, retention of several endothermic regions in post-HF Inceptisol soils indicated that not all minerals were completely solubilized in this soil type. In addition, important differences in the DSC and CO2-EGA thermograms were observed in comparing samples before versus after HF treatments. These results suggest that the organo-mineral associations were substantially altered. What is not immediately clear from the thermal analyses is the degree to which alterations in chemical composition versus binding association have changed. In addition to these qualitative changes, the low yield of NMR-observable C reminds us that 13C-NMR results from low-C and high-Fe soils must be interpreted with caution. Laval University, Soils and Agri-Food Engineering Institut national de la recherche scientifique: Centre Eau, Terre et Environnement 189 University of Pennsylvania Baylor University Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Portable Field Mass Spectrometer for Measurement of Gases in Soils Freeze-thaw cycle impact on macropore flow and nutrient transport through soil monoliths Timothy Porter1, Randy Dillingham 2 Savitoz Sidhu1, Asim Biswas1, Joann Whalen1, Keith Reid2 1 University of Nevada Las Vegas Nothern Arizona University 2 1 McGill University, Natural Resource Sciences Agriculture and Agri-Food Canada 2 Plant life, decomposition and microbes play a complex role in the production of gases, including greenhouse gases, in the soils. The formation of these and other gases depends on many factors relating to the soils themselves, the plants, and the environment in which the plants are growing. We have constructed a portable field mass spectrometer for use in sampling gases in the soils surrounding trees, plants and other areas. In particular, we have used the instrument to sample in real time the greenhouse gases Carbon Dioxide and Methane in soils where plant life may be contributing to the production of gases such as methane. These measurements may be made at varying depths in the soils as the instrument intake is inserted deeper into the ground. The instrument itself utilizes a micro-quadrupole spectrometer, with part per billion or better sensitivity, coupled to battery-powered turbo and diaphragm pumps. A unique ambient air pressure differentially pumped intake apparatus allows for the real-time sampling of gases in the soils from the surface to several inches below the surface. 190 Macropores are direct conduits for preferential movement of water and thus the contaminant and nutrient (e.g. P) transport and can be directly affected by freeze-thaw cycles (FTCs). But FTC effects on macropore flow remain understudied. This preliminary study was conducted to evaluate the challenges likely to be encountered in designing a future experiment on quantifying the changes in soil macropore flow due to subsequent FTCs. For current study, two undisturbed sandy loam soil monoliths (using PVC pipes of 0-25 cm height and 20 cm diameter) were collected and one soil column was exposed to 1 FTC by freezing at -15°C once for 5 days and further thawing at room temperature. Another soil column is being exposed to 5 FTCs, each consisting of freezing for 5 days at -15°C followed by thawing for 5 days at room temperature. At end of each FTC, both soil columns are being spiked with 0.1M RbCl2 followed by flushing of RbCl2 using deionized water to obtain breakthrough curves. Leachates are analyzed for different fractions of P (total, particulate and molybdate malachite green assay) in order to evaluate nutrient outflow from soil columns after each FTC. Initial results (first 2 FTCs) point out towards higher nutrient concentrations (TP and PP) in soil column undergoing 1FTC compared to 5 FTCs. Challenges being encountered in this experiment include; complete retention of RbCl2 in soil columns, frequent cracking of adhesive due to low temperature extremes and detaching of the soil from sides of PVC pipes with subsequent freezing and thawing. To address these issues, alternate tracer like NaCl, smaller diameter cores (15 cm) fitted with base caps and outlet control at bottom will be used for future experiment. Also, changes in macropore quantification and connectivity will be evaluated by conducting image analysis using Image J software. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Advanced analytical techniques for the characterization of soil organic matter composition and biogeochemistry Comparisons of gap filling methods on nitrous oxide fluxes from a corn-soybeanwheat rotation over 6 years Myrna Simpson Rezvan Taki1, Claudia Wagner Riddle1, Robert Gordon1, Andrew VanderZaag2 University of Toronto, Environmental NMR Centre, Environmental and Physical Sciences 1 University of Guelph, Environmental Sciences Agriculture and Agri-Food Canada 2 Soil organic matter (SOM) is critical to ecosystem function, soil sustainability and soil fertility. Environmental change, such as increased temperatures, shifts in moisture regimes, and changes in N deposition, may increase the vulnerability of SOM stocks in various ecosystems. It is hypothesized that climate warming may alter the biogeochemical cycling of SOM through enhanced degradation of labile components reducing soil quality in the long-term. Some studies also suggest that increased plant productivity due to climate warming may increase plant detrital inputs and may offset carbon losses due to warming through enhanced carbon sequestration. Other hypotheses propose that chronic nitrogen addition may suppress SOM degradation and result in an increase in carbon stocks while others have provided evidence for accelerated SOM cycling with N addition. The uncertainty surrounding the fate of SOM with climate change stems from the lack of molecularlevel information about SOM and its response to various aspects of environmental change. The chemical complexity and heterogeneity of SOM requires the use of advanced, molecular-level methods to determine SOM responses to potential ecosystem shifts. This presentation will provide an overview of two powerful, complementary analytical techniques that have been developed to study SOM biogeochemistry in detail: SOM biomarkers and nuclear magnetic resonance (NMR) spectroscopy. SOM biomarker analysis by gas chromatography-mass spectrometry (GC-MS) is a targeted approach that enables the isolation and quantification of specific SOM components (plant-derived and microbial-derive lipids, lignin phenols, cutin and suberin biomarkers). NMR spectroscopy provides an overview of all structures within soil and can be used to study whole soils, soil extracts and conformation of organic matter at the soilwater interface. Studies from field experiments will be highlighted to demonstrate how these techniques provide a molecular- to ecosystem-level understanding of SOM biogeochemistry. 191 Agricultural activities have a significant impact on N2O emissions from soils. Micrometeorological methods are ideally suited to quantify these highly variable emissions in time and space. However, the time series of nitrous fluxes inevitably have periods without reliable values and need to be gap filled. The objective of this study is to compare annual N2O emissions from a corn–soybean–wheat rotation over 6 years obtained through two gap-filling methods. Measurements of N2O flux emissions were conducted at Elora, Ontario, from 2001 to 2006 using the flux-gradient method. The two gap-filling methods used to reconstruct the missing N2O fluxes and evaluate the impact on annual sums of N2O emissions included linear interpolation and artificial neural networks (ANNs). The performance of gap filling techniques was examined by generating 44 scenarios with artificial gaps (ranging in length from 1 to 14 continuous days, as well as combinations of different sized gaps) and the results were evaluated by statistical metrics. The average coefficient of determination of measured vs. predicted N2O flux for all scenarios using ANN (R2=0.41) showed a better performance method compared to linear interpolation technique (R2=0.36). Total annual N2O emissions ranged from 1.18 ± 0.21 to 4.68 ± 0.58 kg N ha-1, across different years and different gap-filling methods. These uncertainty estimates are valuable criteria to compare annual emission estimates obtained with a multi-plot flux-gradient system. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial amino sugars of some Canadian agricultural soils Xueming Yang1, Craig Drury1, S.Bittman2, M. Chantigny3, J. Miller4, E.G. Gregorich5, D. Reynolds1, J. Yang1 1 Greenhouse and Processing Crops Research Centre, AAFC Pacific Agri-Food Research Centre, AAFC 3 Soils and Crops Research and Development Centre, AAFC 4 Lethbridge Research Centre, AAFC 5 Eastern Cereal and Oilseed Research Centre, AAFC 2 Amino sugars (ASs) are an important component of soil organic matter, with concentrations in soil up to 40 times greater than the concentration of living microbial biomass. In addition, amino sugars are potentially useful for tracking changes in microbe composition through time due to their various origins and slower turnover rates relative to living microbial biomass. Hence, the concentration and composition of amino sugars are important determinants of the amount, quality, and characteristics of soil organic matter. The objectives of this presentation are to: (i) examine the variations in the concentrations of amino sugars in soils collected from various sites, including Agassiz in BC (80 samples), Lethbridge in AB (56 samples), Woodslee (50 samples) and Ottawa (30 samples) in ON and Québec city in QC (60 samples); (ii) examine the effect of fertilization (organic or chemical), relative to non-fertilized control, on the accumulation of amino sugars in soils. We found that (1) total ASs varied from 700 to 6746 mg kg-1 and Glucosamine (GluN) was present in the highest concentrations (485–4034 mg kg-1) followed by Galactosamine (GalN) at intermediate concentrations (188–2051 mg kg-1) whereas Muramic acids (MurA) had the lowest concentrations (0-190 mg kg-1) amongst all samples. (2) The highest AS concentrations occurred in the samples of Lethbridge, AB and Agassiz, BC and the lowest AS concentrations were found in the samples of Woodslee and Ottawa, ON. (3) The AS concentrations for the soils of Québec, QC were in the between. Although Québec soils had a lower total AS concentration relative to Lethbridge soils, the former had a different pattern in individual amino sugar concentrations (lower in GluN and MurA but higher GalN), compared with the latter. (4) The average of GluN:GalN ratio was 1.87, varying from 1.70 to 2.00, for the all soils except for the Lethbridge soils which had the highest GluN:GalN ratio of 2.28. The Lethbridge soils also showed highest MurA concentrations, followed by the Agassiz soils, and the sandy soil of Québec. However, no MurA was detected from two Ontario soils (Woodslee and Ottawa, ON) and the clay loam soil of Québec City, QC. Both inorganic 192 fertilizer and organic amendment increase individual amino sugar concentrations. However, the influence was generally lower for chemical fertilizer than organic amendments. The influences of organic amendments also vary with the types of amendments. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S6: Agricultural Greenhouse Gas Emissions 193 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Using proximal soil sensing to optimize assessment of agricultural greenhouse gas emission N2O emissions as affected by fertilization and water table management in southwestern Ontario Viacheslav Adamchuk1, Ahmad Mat Su1, Joann Whalen2, Chandra Madramootoo2, Asim Biswas2, Florian Reumont1, Francisco Ruiz De Le Macorra1, Wenjun Ji1 Naeem Ahmed1, Tiequan Zhang2, Joann Whalen1, Chandra Madramootoo1, Eduardo Genam Cuenca1, Chin Tan2 1 McGill University, Bioresource Engineering 2 McGill University, Natural Resource Sciences Stationary gas chambers are commonly used to monitor greenhouse gas (GHG) fluxes from agricultural fields. Soil spatial variation poses a challenge for identifying the right location to set up these chambers. The objective of this study was to identify representative locations in monitoring GHG fluxes based on the spatial variation of soil properties measured using proximal soil sensing (PSS) technologies. A map of apparent soil electrical conductivity (ECa) measured using DUALEM–21S, radiometric characteristics determined using the SoilOptix gamma-ray spectrometer, as well as field elevation data were used to delineate field areas with different soil conditions. Nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) gas fluxes were monitored at 9 locations with two replicated chambers at each location. The measurements were performed 17 times at 2-week intervals through the entire 2014 growing season in a soybean field with both organic and mineral soils. A total of 1531 gas samples were collected and analyzed in the laboratory using gas chromatography. Fluxes were estimated using the median slope of the linear time response model. In general, organic soil exhibited greater levels of N 2O and CO2 emissions as compared to mineral soils. Substantial differences in the GHG flux estimates between the two chambers at any given location was the main concern limiting the ability to develop highquality spatial models predicting distributions of GHG fluxes. However, it was noted that extreme soil environments recognized by the sensors correspond to extreme GHG observations. 194 1 McGill University Greenhouse and Processing Crops Research Centre, AAFC 2 Soil moisture and bio-availability of nutrients play vital roles in the emission of greenhouse gases viz. N 2O, CH4, and CO2, emitted from soils. The objective of this three-year study was to quantify greenhouse gas emissions as a function of water table management and source of applied soil nutrients. The treatments of the field study included regular free tile drainage (DR) and controlled drainage and sub-irrigation (CDS), each with inorganic fertilizer (IF) and solid cattle manure (SCM), respectively. Gas sampling was conducted using the non-steady state closed chamber approach. In dry years, the soils amended with SCM produced 5.8 to 6.33 g N2O-N/ha/day, which was similar to the values in wet years (i.e. 5.94 to 6.54 g N2O-N/ha/day). In drier years, the N2O emission was similar in plots receiving IF, regardless of water management treatment, which was between 13.88 – 14.71 g N2O-N/ha/day and this declined by 51 to 76% in wet years. The results suggest that increased N2O emission from the IF plots was due to N substrate availability in the soil. The CO2 emission was greater with SCM than with IF, whereas the effect of water management was small and varied with year. All soils acted as a sink for CH4 gas, with greater consumption under DR than with CDS. The results to date indicate high site-specific and temporal variability in greenhouse gas emissions Controlling N substrates and soil moisture can be favorable to mitigating N2O emissions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Glycerol from the biodiesel industry: Can it reduce ammonia volatilization and nitrate leaching in soil treated with liquid manure? Soil-Atmosphere Exchange of Carbon Dioxide, Methane and Nitrous Oxide in Shelterbelts Compared with Adjacent Crop Fields Khaled Alotaibi1, Jeff Schoenau2, Nils Yannikos2 1 Soils and Crops Research and Development Centre, AAFC University of Saskatchewan, Soil Science 2 Expansion in biodiesel production has resulted in a significant amount of glycerol, as a major byproduct of biodiesel industry, being produced. Alternative methods of utilization of this viable byproduct needs to be sought, including its recycling to agricultural soils. A combination of glycerol with liquid manure is postulated to be an effective strategy to reduce NH3 volatilization and NO3 leaching that may occur when large amounts of liquid manure are land-applied. The objective of this study was to evaluate the impact of a combination of glycerol and liquid swine manure (LSM) on NH3 volatilization and NO3 leaching in a cultivated Brown Chernozem soil. The study was conducted under controlled environment conditions and consisted of one rate (4000 kg C ha-1) of glycerol (GL), one rate (200 kg N ha-1) of LSM, added alone and in combination, in addition to an unamended soil (control). Glycerol addition reduced NH3 volatilization from LSM-treated soil. The content of NO3-N in leachate collected during three separate leaching events was greatly reduced by glycerol addition with LSM compared to LSM alone. The observed reduction in both volatilization and leaching is attributed to N added in LSM undergoing immobilization by soil micro-organisms decomposing the glycerol. The results of this study suggest that glycerol has potential use as soil amendment to retain N in soil that is receiving high amounts of inorganic N as liquid manure. 195 Chukwudi Amadi, Richard Farrell, Ken van Rees University of Saskatchewan, Soil Science During 2013 and 2014, soil CO2, CH4 and N2O fluxes were measured from nine shelterbelts and compared with fluxes in adjacent crop fields in three locations within the Boreal plains and Prairies Eco-zones of Saskatchewan Canada, using non-steady state vented chambers. Mean cumulative CO2 emissions from soils underneath shelterbelts (4.1 Mg CO2-C ha-1 yr-1) were significantly greater than emissions from crop fields (2.1 Mg CO2-C ha-1 yr-1). However, SOC storage (0-30 cm soil depth) in shelterbelts was greater than in adjacent crop fields by 28 Mg ha-1, representing a 27% increase per ha of shelterbelts. Cumulative CH4 oxidation was greater in shelterbelts (-0.66 kg CH4-C ha-1 yr-1) than adjacent crop fields (-0.19 kg CH4-C ha1 yr-1) and cropped soils emitted significantly greater N2O (2.5 kg N2O-N ha-1 yr-1) than shelterbelts (0.65 kg N2O-N ha-1 yr-1). Total seasonal exchange of non-CO2 GHGs was reduced by 0.55 Mg CO2e ha-1 yr-1 in shelterbelts as compared with crop fields, 98% of which was soil N2O flux. Whereas increased N2O emissions following the thawing of frozen soils in early spring and following fertilization during seeding operations were significant contributors to the cumulative seasonal N2O emissions in cropped fields, soils beneath shelterbelts were less responsive to the events. Patterns of soil temperature, moisture and organic matter distribution beneath shelterbelts suggest modification in soil microenvironment due to shelterbelt establishment and root activity, which in turn, may be responsible for increased soil CO2 emissions and CH4 oxidation. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Beneficial Management Practices for Greenhouse Gas Mitigation from Agroecosystems Factors Determining Low and High Emissions of Greenhouse Gases from Canadian Beef Cow-Calf Farms Brian Amiro1, Wole Akinremi1, Goretty Dias2, Ehsan Khafipour1, Suren Kulshreshtha3, Kim Ominski1, Christine Rawluk1, Mario Tenuta1 Brian Amiro1, Aklilu Alemu1, Shabtai Bittman2, Doug McDonald3, Kim Ominski1 1 University of Manitoba 2 University of Waterloo 3 University of Saskatchewan We highlight findings from recent research conducted under the Agricultural Greenhouse Gas Program that incorporates multi-disciplinary cooperation among scientists working with animal-plant-soil systems. The research tackles several scales, from in-depth processes to life-cycle analyses. The research explores greenhouse gas processes such as the dynamics of fecal microbial communities, enteric emissions, cattle energetics, and mechanisms generating nitrous oxide from soils. At the field scale, we summarize greenhouse gas exchange studies related to cropping systems and cattle management. We also describe systems modelling of changes to management practices that include life-cycle analyses and economic considerations. The challenges of knowledge transfer and identification of potential beneficial management practices as a consequence of the complex interactions in these systems is addressed. Outreach activities aimed at students and the general public are also presented. 196 1 University of Manitoba Pacific Agri-Food Research Centre, AAFC 3 Environment Canada 2 An extensive survey of about 1000 Canadian beef farms has provided a database of management practices that cover the wide range of farm types in the beef industry. We used information from this database to estimate whole-farm greenhouse gas emissions from 295 cow-calf operations that reported sufficient information to run the HOLOS emissions model. The model included emissions from animals, feed production, manure, and energy used. Changes in soil carbon were not included. Whole-farm emissions ranged from 15 to 37 kg CO2 equivalent/kg live weight sold. The lower quartile emitted less than 20 whereas the upper quartile emitted more than 25 kg CO2 equivalent/kg live weight produced. Farms that were high emitters tended to have both higher methane and nitrous oxide emissions, although enteric methane emissions dominated all other sources. Lower emitting farms had heavier calf weaning weight, had a higher animal replacement rate, and composted a smaller percentage of manure than high emitters. Because enteric emissions dominated, differences in land management practices such as nitrogen application on annual crops had little influence in distinguishing farms for total emissions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Changes in snow cover alter nitrogen cycling and gaseous emissions in agricultural soils Lindsay Brin1, Claudia Brin1, Bernie Zebarth1, David Burton2, Sophie Wertz1, Martin Chantigny3 1 Potato Research Centre, AAFC 2 Dalhousie University, Environmental Sciences 3 Soils and Crop Research Development Centre, AAFC Agricultural ecosystems contribute the majority of global anthropogenic emissions of the greenhouse gas nitrous oxide (N2O), and up to 80% of annual N2O fluxes occur during the non-growing season. Emissions may be related to the depth and duration of snow cover, which may be altered by climate change. To assess the consequences of such changes on N cycling in humid temperate agricultural soils, we conducted a two-year field study with snow removal (Removal), passive accumulation (Accumulation) and ambient (Ambient) treatments. To examine in situ dynamics, we measured N2O fluxes using static chambers, and belowground gas accumulation using soil gas wells. These measurements were coupled with assays of denitrification, potential nitrification, and soil inorganic nitrogen. Results from the first winter indicate that snow cover affected the timing and magnitude of N2O production and fluxes. In December and January, N2O fluxes ceased from Removal plots but were consistent in snow-covered plots, likely due to warmer soils. Potential nitrification rates were low, with no treatment effects. In February and March, gaseous fluxes were blocked by ice and thus negligible in all treatments. During this time, denitrification rates in soil (0-7.5 cm) were greater than in fall or spring, and N2O accumulated at 15 and 30 cm depth in all treatments, with greater concentrations in Removal than Ambient plots. As snow melted and soils warmed in April, potential nitrification increased, and N2O fluxes occurred from all plots. However, fluxes from Removal plots were up to an order of magnitude greater, and began earlier, than snow-covered plots. Taken together, results indicate that snow removal increased N2O production from midwinter onward, possibly because of soil freezing to lower temperatures, which may have increased soil carbon availability. Thus, in future winters with decreased snow, soils could cause a positive climate change feedback via greater N 2O production. 197 Method and timing effect of field applied anaerobically digested and raw dairy manure on soil nitrous oxide emissions from corn production Sebastian Cambareri1, Claudia Wagner-Riddle1, John Lauzon1, Craig Drury2, Susantha Jayasundara1 1 University of Guelph, Environmental Sciences Agriculture and Agri-Food Canada 2 The impact of field applied digested manure is unknown and we hypothesize that N2O emissions may be reduced compared to the application of raw manure. The aim of this research was to compare soil N2O emissions associated with application method (broadcast, B; broadcast + incorporated, BI; injected, I) at two application times (fall vs spring) for anaerobically digested (AD) and raw (R) dairy manure. The field experiment was conducted at Elora, Ontario, in 2013 and 2014. The experimental design was a factorial RCBD with 4 replications. Amendments were applied either in November (fall) or in May (spring), followed by corn planting. Nitrous oxide flux was measured using non-steady state chambers sampled weekly or biweekly. During 2013, the interaction Timing X Method slightly affected N2O emissions (p<0.074), with the highest values (4.7 ± 2.1 kg N2O-N ha-1) for B either AD or R, in fall applied plots. During 2014, an effect of the source (p<0.0026) was observed with greater N2O emissions from AD than from R (6.0 ± 2.4 vs 3.8 ± 2.7 kg N2O-N ha-1). An interaction Timing X Method (p<0.027) was also observed with the largest N2O emissions for B application during fall (6.9 ± 2.5 kg N2O-N ha-1 ) and the lowest for the I applied during fall (3.6 ± 2.6 kg N2O-N ha-1). Also, the emissions during 2014 were affected by the interaction Source X Method (p<0.025), with the highest emissions produced by BI AD applied plots (7.1 ± 2.6 kg N2O-N ha-1) and the lowest for BI R applied plots (2.2 ± 1.7 kg N2O-N ha-1) . Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Associating the potential of organic amendments for soil N2O emissions to their chemical characteristics Anaïs Charles1, Philippe Rochette2, Joann Whalen1, Denis Angers2, Martin Chantigny2, Léon-Étienne Parent3, Normand Bertrand2 1 McGill University, Natural Resource Sciences Agriculture and Agri-Food Canada 3 Université Laval, Soil Science and Agri-Food Engineering 2 Prediction of N2O emissions following the application of organic amendments (OAs) to soils is difficult because of their variable composition and of complex interactions with soil properties and conditions. In this study, we determined the Potential of Organic Amendments to enhance soil N2O emissions POA-N2O of 167 soil amendments and fertilizers, including 150 OAs, 12 inorganic fertilizers, and 5 organo-mineral fertilizers. POA-N2O were estimated under oxic and anoxic conditions during a 90-d laboratory incubation consisting of a 44-d oxic period at constant soil moisture (0.30 g water g-1 soil) followed by a 46-d period under anoxic conditions. The selected OAs included 66 animal manures (liquid and solid), 41 plant residues, 30 composts of varying ages and origins, 5 sludges and biosolids, and 8 organically based commercial products. Amendments and fertilizers were mixed with 220 g of a clay loam soil (dry basis) sieved through 6 mm. A total number of 684 experimental units were set out in a randomized complete block design with four replicates. Starting of each block was delayed by one week. The experimental design included 4 unamended soils per block as control. The POA-N2O (oxic and anoxic) for OA types such as manures, composts, biosolids and crop residues will be presented and related to the chemical characteristics of amendments. 198 Measuring and modelling the long-term impact of crop management on soil C sequestration in the semi-arid Canadian prairies Katelyn Congreves, Brian Grant, Con Campbell, Ward Smith, Bert VandenBygaart, Roland Kröbel, Reynald Lemke, Raymond Desjardins Agriculture and Agri-Food Canada Agricultural management practices which promote soil organic C (SOC) sequestration can help reduce greenhouse gas emissions, thus research must quantify and predict SOC dynamics in response to crop management. Using long-term (1967-2009) data from 10 cropping systems on a Brown Chernozem in the Canadian semiarid prairies at Swift Current, Saskatchewan, we assessed the effect of fertilizer, cropping frequency, and crop type on SOC dynamics in the 0-15 cm depth. Three models: Campbell, Introductory Carbon Balance Model (ICBM) and DayCent were evaluated, all of which produced fairly accurate predictions of SOC content and sequestration rates (R2 of 0.64 to 0.82); however, DayCent had the highest correlation and lowest errors of prediction and was deemed superior. Overall, residue inputs of 0.87 to 1.13 Mg C ha-1 yr-1 maintained the SOC level, and SOC content was directly related to factors which increased C inputs. The SOC content and sequestration rates were lowest for wheat -based rotations which were frequently fallowed and included flax, but highest for systems which were frequently cropped, well-fertilized, and included rye or pulse crops in rotation. For systems with high C input, the DayCent model projected SOC gains of 12 Mg C ha-1 from 20092100, indicating that the soil at Swift Current had not reached maximum C capacity. This study was the first to rigorously test and demonstrate the strength of the DayCent model for simulating SOC under different cropping systems on the Canadian prairies. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Abundance of Ammonia-oxidizing Archaea and Bacteria in Woody Perennial Cropping Systems The role of water-table, soil depth, and nitrogen fertilizer on the interaction of soil microbial biomass and gas emission Geetkamal Hans, Tanja M. Voegel, Louise M. Nelson Stephen Jennewein, Samira Daroub, Jehangir Bhadha, Timothy Lang, Maninder Singh, Mabry McCray University of British Columbia Okanagan, Biochemistry Nitrification in agricultural soils contributes significantly to nitrous oxide emissions which play a role in global warming. The first step of the nitrification pathway is catalyzed by the enzyme ammonia monooxygenase (amoA) which oxidizes ammonia to hydroxylamine which can then be converted to nitrous oxide. The objective of this study was to quantify total and nitrifying, Archaea and Bacteria in apple and grape plots in the Okanagan Valley, British Columbia, Canada at four sampling times (August and September, 2013 and 2014) and at three soil depths (0, 15 and 30 cm). The apple plot received 20 g N/tree (Ca(NO3)2) and the grape plot 15 g N/vine (urea) via fertigation. The abundances of total Archaea and total Bacteria and of the nitrifying Archaea and nitrifying Bacteria were determined based on the copy numbers of the archaeal and bacterial 16S rRNA genes and of the archaeal and bacterial amoA genes, respectively, using quantitative real-time PCR. The abundance of Bacteria was 4 to 8 fold higher in both plots compared to Archaea. The abundance of total Bacteria and Archaea was higher in the grape plot compared to the apple plot and this correlated with higher total nitrogen, total carbon and NH4N concentrations. The abundance of nitrifying Archaea was 5 fold and 2 fold higher in the apple and grape plots, respectively, than that of the nitrifying Bacteria. The abundance of total Archaea and Bacteria decreased significantly as depth increased. The abundance of nitrifying Archaea increased with depth and was negatively correlated with NH4N concentration. These data suggest that the nitrifying Archaea are present at higher numbers than nitrifying bacteria in these woody perennial cropping systems, and are more abundant at lower depths where low concentrations of NH4N may limit their potential contribution to nitrous oxide emissions. 199 University of Florida, Everglades Research and Education Centre The Everglades Agricultural Area (EAA) of southern Florida is a subtropical region of fertile Histosols responsible for roughly half of sugarcane (Saccharum spp. hybrids) production in the USA along with the supply of winter vegetables to the eastern USA. Soil subsidence resulting from oxidation of organic matter has led to shallow soil depth which presents a major challenge to future agriculture in the region. Development of economically feasible and sustainable management practices to reduce organic matter oxidation is paramount to continued production on these shallow organic soils. An ongoing lysimeter study examined effects of management practices (water table and nitrogen fertilizer), and soil depth on nutrient cycling, gas emission, and sugarcane yield. Lysimeters were constructed in Belle Glade, FL, using Lauderhill muck (Lithic Haplosaprists) and crushed bedrock with two soil depths. Results to be presented include soil microbial biomass, soil gas (CO2, CH4, and N2O) flux, available nutrients, and sugarcane yield. This study provides insight into management effectiveness and agriculture sustainability on shallow muck soils of the EAA and will help farmers mitigate problems associated with soil subsidence and seasonally high water-tables. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Green management of sugarcane and its effects on nitrous oxide emissions in Northeastern Brazil Overall evaluation of solid waste composting and agricultural recycling: a methodological framework proposal F.C. Leite Luiz, Mirya G.T. Portela, Diana Signor Jérémy Denes1, Anne Trémier2, Patricia Garnier3, Virginie Parnadeau1, Suzelle Barrington4, Safya Menasseri-Aubry1 Piaui Federal University In Brazil, the trash management of the sugarcane with harvest road green sugarcane has become an alternative to improve soil quality and to mitigate of climate change. The objective of this study was to determine the impact of the green sugarcane management on nitrous oxide emissions estimated by analytical methods and the DNDC model in northeastern Brazil. Five treatments, representing different amounts of straw (T1: 0 Mg / ha, T2: 4.19 Mg / ha; T3: 9.54 Mg / ha; T4: 13.4 Mg / ha; T5: 18:38 Mg / ha) and four replications in randomized block design, were installed in a Plinthosol for determining N 2O emissions. The gas samples were collected using static chambers in treatments T1, T3 and T5 and analyzed by gas chromatography. Nitrous oxide emissions were also estimated by DNDC model, during the period of five harvest seasons (from 2009/2010 to 2013/2014). The N2O flow measured in the soil were not affected by the levels of straw (p < 0.001), ranging from 5.67 kg N-N2O ha-1 (T1) at 7.57 kg N-N2O ha-1 (T5). DNDC estimated that the highest emissions were observed in the treatments with higher levels of soil mulching. Comparing measured and simulated emissions, observed that, in the last harvest season (2013/2014), there was difference of 9% (T1), 18% (T2) and 13% (T3) considered within the margin of error (52%) of II Brazilian Inventory of Greenhouse Gas Emissions from agricultural soils, indicating that the DNDC can simulate deN2O flows in areas under green sugarcane management in the Northeastern Brazil. 200 1 INRA, UMR INRA/Agrocampus Ouest « Sol Agro et hydrosystème Spatialisation » 2 Irstea, UR “GERE” 3 INRA, UMR INRA/AgroParisTech “ECOSYS” 4 Concordia University, Civil and Environmental Engineering The French national inventory realized in 2010 pointed out a contribution of 17.8 % from the sector of the agriculture to the GHG emissions. The optimization of the organic waste management through recycling in cultivated soils is one of the identified pathways for climate change mitigation. In 2009, in France, 517 Mt of waste have been produced (ADEME, 2012), which represents a considerable amount of potentially reusable organic matter. Biological treatment of organic waste contributes to limit greenhouse gas emissions, to increase the potential of carbon storage in the soils and to provide a substitution to the mineral fertilizers. To be sure to propose an appropriate design and management scheme, it is necessary to overall assess the fate of the organic matter and nutrients from the waste entering the treatment to the evolution of the product in the soil. Such an assessment can be obtained through the coupling of biological treatment models with models of C and N dynamics in soils. We propose a conceptual way to couple models as a first step of construction of a useful decision support tool. It implies (i) to characterize organic matter biodegradability in the same way for both types of models and (ii) to calibrate the models with a unique set of parameters for all the organic products. Van Soest organic matter fractionation method was retained to characterize the different organic matter pools. Laboratory soil incubations with the products studied during composting have been performed in order to calibrate agronomic models. Urban and agricultural organic products were studied and compared. Even if some improvements are still needed, the first results of modeling calibration based on a homogeneous way of organic matter pools initialization for all the models and leading to a unique set of parameters for each model are promising. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Development of a simplified and economical technology to measure N2O and CH4 emissions from livestock buildings Comparison of Methods for Predicting Pore Space Indices in Corn-Soybean Field Dinesh Panday, Nsalambi Nkongolo Joahnn H. Palacios1, Stéphane Godbout1, Dan Zegan1, Patrick Dubé1, Araceli Dalila Larios1-2, Beatriz Delgado Cano1-3 1 IRDA (Research and development institute for the Agrienvironment), Canada 2 INRS (Institut National de la Recherche Scientifique), Canada 3 Université de Lyon, France The objective of this project is to develop an economical and practical sampler and the protocol to measure N2O and CH4 emissions from livestock buildings. The technique used by this device in development is the passive flux sampling. This technique has been used to measure NH3 emissions, however no references have been reported for the measurement of N2O and CH4 emissions. In this technique, the sampler faces the building ventilation airflow, a part of the flow passes through the sampler and the target gas is then captured by adsorption. After the sampling period, the gas adsorbed is desorbed and quantified, and the emission is then calculated. One key aspect of this technique is that the rate of adsorption of the sampler must vary linearly with respect to the emission airflow. This is achieved by (i) adsorbing 100% of the target gas going through the sampler, and (ii) a suitable aerodynamic shape of the sampler allowing always a proportional ratio between the flow inside and outside the sampler. Therefore, in contrast to other techniques, neither gas concentrations nor air speeds have to be measured in the field, simplifying the protocol. Two samplers prototype were developed and evaluated at laboratory scale using zeolite 5A as N2O adsorbent. Adsorption was close to 100 %, however, a highly variable desorption efficiency (20 to 98%) was obtained according to the technique used. Furthermore, an adequate aerodynamic behavior was obtained when samplers were exposed to airflows ranging 1 to 7 m s1 (0.99 and 0.97 R2 linearity). In future tests, samplers will be evaluated in semi-real and real conditions. In the case of CH4 emissions, work is currently underway in order to find or develop an appropriate adsorbent because zeolite 5A adsorbed only less than 15%. 201 Lincoln University, Agriculture and Environmental Sciences Soil pore space indices (gas diffusivity, Ds/Do and pore tortuosity, τ) are potential controlling factors for greenhouse gas emissions and other soil processes. However, measurement of these indices are tedious. Several models predict these indices, but information is lacking on which models predicted indices better relate to soil processes. The objectives of this study were (i) to compare pore space indices predictive models based on air-filled porosity (AFP) alone vs models using air-filled porosity and total pore space (AFP+TPS), and (ii) to assess the relationships between pore space indices and greenhouse gas emissions (CO2 and N2O). The study was conducted from 2011 to 2014 on a silt loam soil at Freeman farm of Lincoln University of Missouri. Soil samples were collected at two depths: 0-10 and 10-20 cm and were oven dried at 105°C for 72 h. After drying, AFP and TPS were calculated, and later used in Marshall, Buckingham, Sallam, Millington and Jin-Jury models for predicting Ds/Do and τ. CO2 and N2O were measured using a Gas Chromatograph in 2011 and 2012 while a Photo Accoustic Gas Analyzer was used in 2013 and 2014. Results showed that Ds/Do predicted using AFP alone (Marshall and Buckingham) was higher as a compared to values predicted with models based on AFP+TPS (Sallam, Millington and Jin-Jury) (p < 0.001). However, the opposite trend was found for τ, where values predicted with models based on AFP alone were the lowest (p<0.001). CO2 was significantly correlated with Ds/Do predicted from AFP alone (r= 0.50, p<0.05) as well as Ds/Do predicted from AFP+TPS (r= 0.53, p<0.05). Similar results were found for τ. Inclusion of Ds/Do and τ in predictive models will certainly improve our understanding of the dynamics of greenhouse gas fluxes from soil. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluation of the effect of depth and distance of subsurface drainage systems on methane gas emissions The Effect of Nitrogen Fixation on Direct and Indirect Nitrous Oxide (N2O) Emissions in Dairy Crop Rotations Mahmoud Raeini-Sarjaz, Morteza Hashemi, Ali Shahnazari Jessica Singh1, Andrew VanderZaag2, Anna Crolla3, Chris Kinsley3, Claudia Wagner-Riddle3, Ed Gregorich2 Sari Agricultural Sciences and Natural Resources University 1 Global warming and, as its consequences, climate change, are the major concerns of decision makers for assessments of possible impacts on environment. Mitigation and adaptation to these changes are highly necessary to reduce vulnerability. Reduction of human induced emissions of greenhouse gases is one of the strategies to fulfill these concerns. Rice paddy field is the main agricultural sector which emits methane to the atmosphere. Water management could mitigate methane emission effectively. Therefore, the aim is to investigate the effect of rice paddy field water management on methane emission. For this purpose a complete randomized block design with three replications and 7 treatments was carried out in Sari Agricultural Sciences and Natural Resources University research station, Sari, Iran. Drainage water management treatments consisted of 1) conventional paddy plots, non-drained (C), 2) paddy plots with surface drainage (SD), 3) subsurface drainage of 90 cm depth by 30 m length (SSD90-30L), 4) subsurface drainage of 65 cm depth by 30 m length (SSD65-30L), 5) subsurface drainage of 65 cm depth by 15 m length (SSD65-15L), 6) bi-level subsurface drainage of 90 and 65 cm depths by 15 m length (BSSD90-65-15L), and finally, bare soil (BS). Midseason drainage significantly reduced methane emission rate relative to conventional practice. One week after the first drainage all subsurface drainage systems emission rates dropped sharply, while the response of surface drainage was slow, and it reached to a significant difference with conventional practice two weeks later. Among subsurface practices, drainage distance was more affective relative to drainage depth. During the whole season subsurface, SSD65-15L, system was the most effective one, which reduced methane emission by 146 percent relative to conventional practice. It could be concluded that medium subsurface depth with short distance drainage are the most effective practices in reducing methane emission rate in rice paddy fields. 202 University of Guelph, Environmental Sciences Science and Technology Branch, AAFC 3 University of Guelph, Campus d’Alfred 2 In this study we are evaluating the effect of nitrogen fixation on both direct N2O and indirect N2O emissions within typical dairy crop rotations. N2O flux (direct) measurements began in May 2014 and dissolved N 2O fluxes (indirect), from the degassing of tile drainage water, began in March 2015, and are ongoing. The site in Alfred, ON, permits the experiment to be replicated on two soil types: sandy loam and clay. Four croprotation treatments are arranged in a randomized complete block design with three replicates: corn-corn, soybean-corn, corn+cover crop (red clover)-corn, and alfalfa-alfalfa. The treatments were selected to represent a gradient of nitrogen fixation from no legumes (i.e. continuous corn treatment) to all legumes (i.e. continuous alfalfa treatment). Direct N2O flux measurements occur once/week during the snow-free period and twice/month during the winter. Indirect N2O flux measurements occur up to twice/week during periods of tile outflow. Preliminary results show that averaged over 10 months and across both fields, corn fertilized with liquid manure had the highest N2O fluxes (0.019 kg N2O-N ha-1 d-1) followed by soybean (0.018 kg N2O-N ha-1 d-1) and alfalfa (0.017 kg N2O-N ha-1 d1). When averaged by soil type, however, alfalfa had the highest fluxes in the clay field at 0.025 kg N2O-N N ha-1 d-1 (corn: 0.020 kg N2O-N ha-1 d-1, soybean: 0.017 kg N2O-N ha-1 d-1) and in the sandy loam field, soybeans had the highest average fluxes at 0.018 kg N2O-N ha-1 d-1 (corn: 0.017 kg N2O-N ha-1 d-1, alfalfa: 0.008 kg N2O-N ha-1 d-1). Thus there appears to be an interaction between soil type and crop-type influencing N2O fluxes. Results of this study will contribute to optimizing the management of dairy crop rotations and feed rations as a means of reducing greenhouse gas emissions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Grazing influences C and N storage in the Northern Great Plains Bert VandenBygaart1, X. Wang1, Brian McConkey2 1 Eastern Cereal and Oilseed Research Centre, AAFC Semiarid Prairie Agricultural Research Centre, AAFC 2 Grasslands in the Northern Great Plains (NGP) represent a large agro-ecosystem that supports an important livestock industry. Grazing potentially alters ecosystem carbon (C) and nitrogen (N) pools and cycles but the overall direction and magnitude as well the absolute values of such alterations are poorly quantified. We undertook a meta-analysis involving 52 experiments from Canada and the U.S. assessing the effects of grazing on C and N pools, fluxes and cycles in NGP ecosystem. Grazing enhanced C stocks in root (+17%) and soil (+14%) but reduced C stocks in shoot (-10%), litter (-40%) and soil microbes (-12%). Grazing enhanced N stocks in soils (+12%) but reduced N stocks in litter (-62%) compared to native-control. Grazers accelerated N cycles and increased the rate of litter (+73%) and root decomposition (+94%), soil N mineralization (+26%), soil NH4+ (+60%) and NO3(+58%) concentrations in NGP ecosystems. Absolute amounts of C sequestration was estimated to be 3.38 Mg C ha-1 with a rate of 0.16 kg C ha-1 yr-1. Absolute N sequestration was estimated at 0.40 Mg N ha -1 with a rate of 6 kg N ha-1 yr-1. The sequestration of C and N was only detected in the top Ah/0-15 cm layers and such sequestrated potential is finite. Generally, NGP grasslands acted as a C sink in their surface layers in the last 80 years. Efforts made by range managers, researchers, and governments have successfully led to the restoration of the Canadian prairies to a C-rich state since their severe deterioration during the first half of the 20th century. 203 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S7: Chemical and Biological Controls on Organic P Cycling in Terrestrial and Aquatic Environments 204 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The influence of phosphorus fertilization on grassland soil phosphorus forms: A 31P-NMR study An investigation of the origins of inositol hexakisphosphate stereoisomers in crested wheatgrass pasture soils Dalel Abdi1, Barbara Cade-Menun2, Noura Ziadi1, Yichao Shi1, Gilles Bélanger1, Julie Lajeunesse1, Jean Lafond1 Barbara Cade-Menun 1 Soil and Crops Research and Development Centre, AAFC Semiarid Prairie Agricultural Research Centre, AAFC 2 Phosphorus (P) fertilization has been shown to influence soil P forms and the preferred technique to characterize soil P forms is 31P nuclear magnetic resonance (NMR) spectroscopy. Our objective was to assess the effect of mineral P fertilization on soil P forms at two grassland sites located at Lévis (QC) on a Kamouraska clay and at Normandin (QC) on a Labarre clay loam. Four P rates (0, 10, 20, and 40 kg P ha -1), replicated four times, were applied each year since 2010 to a previously established timothy (Phleum pratense L.) sward at the two sites but only three replications and three P rates (0, 20, and 40 kg P ha-1) were considered in this study. Soil samples to a 10 cm depth were collected in fall 2013 and were analyzed for different parameters including available P as extracted by Mehlich-3 solution (PM3, the recommended method for soil test P in Québec) and P forms as extracted with solution 31P-NMR. At the two sites, PM3 was greater with the higher rate of P fertilization (31.2 and 76.0 mg kg-1 at Lévis and Normandin, respectively) than without P (13.1 mg kg-1 and 16.8 mg kg-1). Phosphorus fertilization significantly (p < 0.05) increased the concentrations of orthophosphate and P-choline, whereas the application of 20 kg P ha-1 significantly (p < 0.05) decreased D-chiro-IP6 at Lévis site. Results related to 31P-NMR for the Normandin site will be presented and discussed. 205 Semiarid Prairie Agricultural Research Centre, AAFC Inositol phosphates have been recognized for many years as an important component of soil organic phosphorus (P). The most commonly identified soil inositol phosphate is phytate [myo-inositol hexakisphosphate (IP6)]. In recent years, the use of 31P-nuclear magnetic resonance (NMR) spectroscopy has identified other IP6 stereoisomers, including scyllo, neo- and L-chiro-IP6. Soil phytate originates from terrestrial plants, particularly seeds, where it is a P storage compound. The source of other soil IP6 stereoisomers is unclear. They may also originate from plant components, they may be synthesized de novo in soil by soil microbes, or they may occur from the transformation of phytate by soil microbes. In a recent study of soils in Southwestern Saskatchewan, Canada, soils under pastures of the introduced species crested wheatgrass (Agropyron cristatum (L.) Gaertn.), contained low concentrations of phytate and significantly higher concentrations of other IP6 stereoisomers, especially L-chiro-IP6, than soils under other land uses (including native pasture and cropland). To determine the source of these other IP6 stereoisomers, soils and plants were collected from other crested wheatgrass pastures and from greenhouse-grown crested wheatgrass plants. Plants were separated into roots, stems and leaves, which were extracted with NaOH-EDTA and analyzed by 31PNMR spectroscopy. This paper will present the results of that investigation. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Impact of long-term application of composted organic residue on soil organic and inorganic phosphorus dynamics Short-term transport and transformation of phosphorus species from a poultry manure amended soil during leaching Hada Damar1, Noura Ziadi2, Rodolphe Lauverjon3, Alain Mollier3, Sabine Houot3, Guillaume Bodineau3, Jean Noel Rampon3, Léon-Étienne Parent1, Christian Morel3 Courtney Giles1, Barbara Cade-Menun2, Corey Liu3, Jane Hill4 1 Université Laval, Soils and Agri-Food Engineering Agriculture and Agri-Food Canada 3 INRA, UMR 2 Urban composts represent a significant reservoir of nutrients, particularly phosphorus (P). Their application in agriculture requires more information on their impact on the dynamics of soil P. In this study, the long-term effects of repeated applications of urban composts and manure on the dynamics of organic P (orgP-SW) and inorganic P (inorgP-SW) stocks using the Saunders and Williams’ (SW) method were analyzed in the soil of the Qualiagro field experiment (4 blocks), grown in a corn / wheat succession. Five treatments were studied: a control without P (CONTROL), a cattle manure (MANURE) and 3 urban composts: compost green waste + sludge (DVB), a biowaste (BIO) and residual household waste (OMR). They were added to soils on the basis of 4 t C / ha every two years over a period of 15 years. We determined the orgP-SW content in the applied products and the plough layer by difference between P extracted by sulfuric acid (0.1M) in a calcined sample (totP-SW) and not calcined (inorgPSW) samples. All products mainly contained inorgPSW (81%) because orgP-SW averaged 19% for the 3 urban composts and manure. The average orgP-SW soil content in 2013 was 31% of Ptot-SW and did not differ among treatments. After 15 years, cumulated balance of added minus exported P varied between 351 (± 12) kg P ha-1 in CONTROL and +1292 (± 21) kg P ha-1 in the DVB treatment. Despite these differences, the stock of total organic P was invariant across most treatments but in the manure treatment where it was higher. Variations in inorgP-SW and total P stocks reflected differences in P balances. 206 1 James Hutton Institute Semiarid Prairie Agricultural Research Centre 3 Stanford University, Magnetic Resonance 4 Darthmouth college, Engineering 2 The leaching of phosphorus (P) from soils is a major concern in heavily fertilized agricultural regions. The mobility and transformation of P species in the soil profile will depend on the source of manure fertilizer, degree of P saturation (DPS), and the timing and intensity of leaching. We investigate the distribution of P species within a poultry manure-amended soil at two depths (0-5, 10-15 cm) as well as leachate P fractions during 10 weeks of leaching. The maximum loss of P from soils occurred after four weeks of leaching, when dissolved P forms were greatest. The DPS (80%) and water extractable P (9 mg/kg) were greatest during peak leaching. 31P NMR spectra of the 0-5cm depth indicate that surface soils were most similar to the poultry manure and likely contributed to the mobile P pool in the forms of orthophosphate (OrthoP), myoinositol hexakisphosphate (myo-IHP), and nucleic acids. The difference in P species distribution between depths was greatest during the peak leaching period, with high proportions of OrthoP at the soil surface (80% at 0-5 cm vs 72% at 10-15 cm) and relatively larger proportions of monoester-(17%) and diester-P classes (10%) at 10-15 cm. The appearance of neo- and Dchiro-IHP, as well as phospholipid signals indicate possible short-term (< 10 wk) contributions of organic P to the generation and leaching of OrthoP under Psaturated conditions. The concurrent characterization of P forms in soil and leachate is a useful approach for understanding the magnitude and timing of P loss from fertilized soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Phosphorus transformations and mobility in the rhizosphere of phytase-exuding plants following a single cultivation cycle C:P stoichiometry in Canadian peatlands and forest litter Tim Moore1, Meng Wang2, Drew Pinsonneault1 Giles1, Menezes-Blackburn2, Courtney Daniel Timothy George1, Lawrie Brown1, Charles Shand1, Renate Wendler1, Pat Cooper1, Marc Stutter1, David Lumsdon1 1 James Hutton Institute Lancaster University, Environment Centre 2 Plant exudation of organic anions and phytases is expected to influence the availability of sparingly soluble and organic forms of phosphorus (P). However, few studies have investigated the effect of plant exudation traits on the depletion of P species in soils. Furthermore, multiple cultivation cycles may be needed to observe changes in the distribution of P species, or the depletion of specific forms such as the inositol phosphates. We utilize wild-type and transgenic plant lines of tobacco expressing an Aspergillus niger phytase (PhyA) to investigate P transformations in an arable soil during a single cultivation cycle (11 weeks). Preliminary results show that soils cultivated with transgenic plants were on average 0.2 pH units higher than soils from wild-type plants and plant-free controls (pH 6.4; p = 0.0206). Phytase-exuding plant lines accumulated more shoot P than wild-type and vector control plants, which may indicate the pH-dependency of phytase function in this system. Additional analyses by solution 31P nuclear magnetic resonance spectroscopy (NMR) and diffusive gradients in thin films (DGT) will be used to discuss the relative influence of a single cultivation cycle on P mobility and organic P turnover in the rhizosphere of plants with varied exudation profiles. 207 1 McGill University, Geography Northwest A & F University, Forestry 2 We examine patterns of C:P in the vegetation and peat at the Mer Bleue peatland, which suggests that plants are co-limited by N and P. As the peat decomposes, the C:P ratio increases, from about 750:1 in plant litter to 2000:1 in the peat profile. This pattern of increasing C:P ratio with depth is replicated in data from over 400 peat cores in Ontario, representing bogs, fens and swamps. At Mer Bleue, phosphatase concentrations are high, much of the soluble P is in organic forms and the plants and phosphatase respond to the application of N and P in a long-term fertilization study. In contrast, the CIDET long-term litter decomposition study, comprising 10 foliar litters over 12 years at 22 forested sites across Canada, revealed that as decomposition proceeded C:P ratios converged, resulting in an average C:P ratio of 427:1 when 20% of the original C remains. We suggest reasons for these divergent patterns as soil organic matter decomposes. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 P pools and microorganisms response to a 5-year P fertilization pot trial for wheat only in a rice-wheat rotation in paddy soils in the Taihu Lake Region of southern China Yu Wang1, Wang1, Sheng-qiang Wang2 Xu Zhao1, Noura Ziadi1, Yichao Shi1, Aime Messiga2, Christian Morel3 Lei 1 Chinese Academy of Sciences, Soil Science 2 Nanjing Institute of Environmental Sciences, Organic Food Development Center The need for efficient use of phosphorus (P) in agriculture has been highlighted recently by concerns about the finite amount of P fertilizer resources. However, in the Taihu Lake Region (TLR) of China, farmers’ injudicious and excessive use of phosphorus (P) fertilizer has led to a dramatic spike in P accumulation. In view of that, a five-year (ten consecutive crop seasons) pot experiment was conducted using four paddy soils with three P concentrations (high, medium, and low P-status) from the TLR under four P fertilization regimes; P fertilization only for the wheat season (PW), P fertilization only for rice (PR), P fertilization for both rice and wheat (PR+W), and no P fertilization during either season (Pzero; control). We demonstrated that the PW fertilization regime during the yearly rice-wheat rotation over five years showed no significant difference in crop yields (P < 0.05), because it could supply enough effective P sources (156-328 mg kg-1 labile P and moderately labile P) for crop growth and similar microorganism community structure, although the Olsen-P concentration was reduced by more than half, when compared with the PR+W treatment. Additionally, applied P fertilization decreased acid phosphatase enzyme activity and increased the total relative abundance of microorganisms in P-rich soil, although they decreased in P-deficient soil. Gram-negative (G-) bacteria and arbuscular mycorrhizal fungi (AMF) showed significant positive correlations with soil labile P (P < 0.05), which indicated that G- bacteria and AM fungi play important roles in the transformation of P in the soil P pool. Therefore, our future research will focus on effective utilization of G- bacteria and AM fungi, which are related to P availability in the soil, in a P fertilization regime applied only for the wheat growing seasons. 208 Long-term phosphorus fertilization and tillage impact soil phosphorus transformation and distribution 1 Agriculture and Agri-Food Canada Trent University, Environmental and Resource Studies 3 INRA, UMR 2 Managing and monitoring soil phosphorus (P) changes under different tillage systems remain a major issue to improve P use efficiency and sustain agricultural production. The use of long-term field experiments in agronomic research is an excellent tool to study ecosystem dynamics including the effects of management practices on soil fertility, i.e., P availability and dynamics. We evaluated the combined effects of long term (22 years) mineral P fertilization (0, 17.5, and 35 kg P ha-1 applied every two years on corn phase) and tillage [mouldboard plow (MP) vs. No-till (NT)] on soil P availability and distribution. The field experiment was initiated in 1992 at L’Acadie in southern Quebec on a clay loam soil cropped with grain corn–soybean rotation. Soil P availability was evaluated in different depths (0-1; 1-2; 2-3; 3-4; 4-5; 0-5; 0-15 cm), years, and seasons using different methods. After 12 and 22 years following establishment, NT enhanced Mehlich-3 and Olsen P in the upper soil layer (0-5 cm), likely due to the absence of mixing of soil, fertilizer, and crop residues. More specifically, a P stratification under NT was obtained along the soil profile with accumulations at 0-1 and 0-5 cm, but depletions at lower layers. Soil P adsorbed on anionic exchange membranes (AEM-P) over winter (mid-November to mid-April) in five consecutive years (2009 to 2014) indicated that P fertilization increased AEM-P in both tillage systems, but at a greater extent under NT. We conclude that the addition of P fertilizer in NT systems changes the dynamics of P in the rooting zone, suggesting the importance of approaches to monitor P dynamics specifically tailored for NT systems that integrates the variability caused by the absence of mixing the fertilizer, residues, and soil. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S8: Microbial Provision of Essential Services across Managed and Natural Ecosystems 209 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Diversity and abundance of rhizobacteria encoding phosphatase gen from Chilean extreme environments Thermodynamic profiles and carbon use efficiency of soil microbial communities in contrasting agroecosytems Jacquelinne Acuna, Paola Duran, Maria de la Luz Mora, Milko Jorquera Melissa Arcand, Bobbi Helgason Scientific and Biotechnological Bioresource Nucleus (BIOREN-UFRO) Bacterial communities associated with roots (rhizobacteria) carry out functions that are essential to plant nutrition in terrestrial ecosystems. Rhizobacteria that inhabit extreme environments produce enzymes adapted to those environments. The goal of this study was to evaluate the diversity and abundance of phosphatase-producing rhizobacteria from Chilean extreme environments. We analyzed rhizospheres samples from Atacama Desert (AD), Quetrupillan volcano (QT), Maluil-malal sector (ML) from Lanín volcano, natural hot spring from Liquiñe (LQ), Patagonia (PT) and Antartic (AN). Our results showed that significant differences in the presence of dominants bands were observed in samples from Atacama Desert (AD) and Patagonia (PT), in relation to samples from La Araucanía (QT and ML) and Los Ríos (LQ). According to this differences, UPGMA clustering analysis revealed the existence of three major groups with a similarity of 40% for Patagonia (PT) and Antarctic (AN), following by La Araucanía (QT and ML) and Los Rios region (LQ), and finally Atacama desert. Occurrence of 16S rRNA copies was high in samples from La Araucanía (QT and ML) and Los Rios region (LQ), whereas soils from zones geographically differentiated such as; Atacama Desert (AD), Patagonia (PT) and Antarctica (AN) shown less copies to constitutive 16S rRNA from bacterial communities. The presence of BPP gene was detected in samples obtained in Quetrupillan volcano (QT) from La Araucanía region. Genotyping across ERIC-PCR was a validate method for evaluate genetic diversity between strains with the similar phenotypes. In our study, the 6 sampling sites along of Chilean extreme ecotypes have shown a high diversity of genotypes (ranging from 29% to 66% of different genotypes). This study showed that Chilean ecosystems contains a wide rhizobacterial diversity and highlight our limited knowledge of their ecology, interaction with plants, and their potential as plant growth promoting rhizobacteria based on the production of phosphatase 210 Agriculture and Agri-Food Canada Soil organic matter formation and its turnover are central to ecosystem functioning. Stabilization of C in soils is partly controlled by how effectively soil microorganisms convert C to biomass versus how much of it is lost in gaseous or soluble forms. Heterotrophic microorganisms produce extracellular enzymes to catalyze the transformation of soil organic C, thus breaking C bonds and releasing energy to fuel metabolic processes. Decomposition and the resulting flows of C through the soil are therefore accompanied by flows of energy, and soil microorganisms that can convert C into biomass more efficiently will also generate less waste heat (energy). Since C and energy are intricately linked, using isothermal microcalorimetry to measure heat production in soil can provide valuable insight into C flows, thus improving our ability to predict how C may flow through soils under varied management or land use histories. The objective of this study was to compare thermodynamic profiles and C use efficiency and relate these measures to microbial community composition in soils from a long-term field trial comparing organic and conventional farming systems under varied cropping histories. Microbial biomass C was highest under the conventional system cropped to a diversity of annual grains, followed by the organic system cropped to a diversity of annual grains and perennial alfalfa. Peak heat production occurred more quickly and was smaller in magnitude in soils from the organic compared to conventional system, reflecting a lower store of simple SOC. Further work will examine microbial community composition and whether it relates to the thermodynamic profiles in these soils. Isothermal microcalorimetry has the potential to provide more detailed information on microbially driven C dynamics, which may not be captured by measuring soil respiration rates alone. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 13 The Use of a Conceptual Model to Determine Biological Soil Crusts as the First Terrestrial Ecosystem: Their Role in Embryophyte Land Colonization C cellulose assimilation in different transplanted Chernozems after 21 years of common management and climatic conditions Jessica Arteaga1, Sharon Cowling2 Bobbi Helgason1, Panchali Katulanda2, Fran Walley2 1 Laurentian University, Biology University of Toronto, Earth Science 2 1 Saskatoon Research Centre, AAFC University of Saskatchewan, Soil Science 2 The puzzle of understanding the colonization of life on land has proven difficult for scientists, primarily because of the absence of fossils documenting early land colonizers. Many of the organisms thought to be associated with the first terrestrial ecosystems do not preserve well in sediments, resulting in little or no recognition of their presence in the fossil record. Biological soil crusts (BSCs), sometimes referred to as cryptogamic or cryptobiotic soil crust, have been considered the missing link between aquatic life and land plant colonization. Biological soil crusts develop when soil particles and cyanobacteria, algae, microfungi, lichens, and/or bryophytes are intertwined in a cohesive association with one another. Understanding the role of BSCs in an early environmental setting can provide a clearer explanation for land colonization of embryophytes during the Ordovician. Spectra data collected from the Soebatsfontein Region in South Africa shows that biological soil crusts have a lower albedo at all soil compositions; this indicates that BSCs are absorbing more thermal energy than bare soils. From this, a conceptual model was created to exhibit how BSCs would have regulated temperature through physical properties, thus creating favourable conditions for early embryophytes. Albedo, the fraction of reflected incoming solar radiation, and thermal inertia, the time it takes a body’s temperature to reach equilibrium with its surroundings, were some of the essential properties included in the conceptual model. Through temperature regulation, nutrient cycling, and soil stabilization, BSCs would have altered the early terrestrial landscape creating favourable growth conditions for other organisms, similar to their role in contemporary arid and semi-arid regions. These abilities of BSCs place them as a potential candidate for the first terrestrial ecosystem. 211 Microbial decomposition of crop residues affects agroecosystem productivity and sustainability by governing C cycling in soil. The efficiency with which C is utilized by soil microorganisms during decomposition often varies among different soils however it is difficult to decouple the effects of microbial community structure from environmental factors such as climate and topography which vary from site to site. The Soil Quality Experiment at AAFC Lethbridge provides a unique opportunity to address these differences. In 1991, different Chernozemic soils were transplanted to a common location and have been managed identically under continuous wheat cropping with and without N fertilizer addition since that time. We conducted a 78 d incubation experiment using 13C cellulose to observe the active decomposer community in four different transplanted soils. During incubation, CO2 respiration and changes in microbial community structure using phospholipid fatty acid profiling (PLFA) was measured. Cumulative C mineralization was significantly affected by soil type (P < 0.003), N rate (P < 0.02) and cellulose application (P < 0.0001). Even after two decades under identical management, topographic and climatic conditions, microbial C assimilation remains largely determined by soil origin. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Microbial communities and nitrogen cycle in reclaimed oil-sand soils Jacynthe Masse1, Sue Grayston1, Cindy Prescott1, Sylvie Quideau2 Abundance and gene expression of bacterial and archaeal ammonia monoxygenase (amoA) in a monoculture versus a diverse crop rotation, under conventional and no-till management 1 University of British Columbia University of Alberta 2 The Athabasca oil sands deposit is one of the largest single oil deposits in the world. To date, an area of about 715 km2 has been disturbed by oil sands mining activity. Following surface mining, companies have the legal obligation to restore soils so that they can support the previous land capabilities. Nitrogen availability is fundamental to site productivity; re-establishment of the nitrogen cycle between these reconstructed soils and plants is one of the most critical factors required to insure long-term sustainability of this reclaimed boreal landscape. Soils from a series of 20 sites, covering different vegetation treatments both in reclaimed and naturally fire-disturbed sites were investigated. Gross nitrogen transformation rates were measured using 15N pool-dilution. Microbial communities were characterized using next-generation sequencing method. Reclaimed sites had significantly higher levels of nitrogen and higher microbial biomass-C. However, reclaimed sites did not have higher gross rates of Ntransformation than natural sites. Reclaimed sites had higher rates of ammonification and immobilization from recalcitrant organic-N compared to natural sites. However, natural sites had higher rates of ammonification from the labile organic-N pool. No differences among sites were found for gross nitrification rates. Reclaimed sites produced more NO3 than they immobilized, resulting in positive net nitrification rates. We hypothesize that microbial community composition varies between natural and reclaimed sites, which explain differences in the Ncycle. 212 Jake Munroe, Ian McCormick, Kari Dunfield* University of Guelph, Environmental Sciences Ammonia oxidizing bacteria (AOB) and archaea (AOA) both mediate soil nitrification and have been hypothesized to have specialized and differentiated niches. Relatively little is understood of how abundance and ammonia oxidizing gene expression of these microorganisms are affected by long-term crop rotation and tillage practices. In this study, we used quantitative polymerase chain reaction (qPCR) and reverse transcription techniques to assess abundance and gene expression of AOB and AOA under two contrasting crop rotations and tillage regimes at a 30year old long-term experiment on a Canadian silt loam soil. Continuous corn (Zea mays L.; CC) was compared with a relatively diverse rotation of corn, corn, soybean (Glycine max L.), winter wheat (Triticum aestivum L.) under-seeded with red clover (Trifolium pretense L.), with conventional tillage (CT) and no-till (NT) as subplot treatments. Soil sampling was performed during the first corn year at four time-points throughout the season and at three discrete depths (0-5, 5-15, and 1530 cm). Overall, AOA abundance was found to be more than 10× that of AOB, though AOA transcriptional activity was below detectable levels across all treatments. Crop rotation had a marginally significant effect on AOB abundance, with 1.3× as many gene copies under the simpler CC rotation than the more diverse RC rotation. More pronounced effects of depth on AOB abundance and gene expression were observed under NT versus CT management, and NT supported higher abundances of total archaea and AOA than CT across the growing season. We suggest that AOB may be more functionally important than AOA in this high-input agricultural soil, but that NT management can promote enhanced soil archaeal populations. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Fungal Diversity Associated with Pulses and its Influence on the Subsequent Wheat Crop in a 2-Year Study Adriana Navarro Borrell, Chantal Hamel, Bainard Luke, Jim Germida Semiarid Prairie Agricultural Research Centre, AAFC This study characterizes the fungal diversity associated with chickpea, pea, lentil and wheat and evaluates the effects of these previous crops on overall fungal communities and re-cropped wheat attributes in a 2-year field study conducted in Swift Current, Saskatchewan. No crop effect influenced the relative abundance of AM fungal OTUs inhabiting the roots of pulses and wheat in phase I of the rotations. During phase II, the roots of wheat grown after pea in year/site 2011 hosted an AM community significantly different from that of wheat grown after wheat or lentil. The AM community associated with the roots of wheat was different from that found in the soil after the pulses were harvested. However, the community inhabiting the roots of wheat grown after wheat remain similar to the previous year’s suggesting there is a strong influence of plant cover on AM fungi abundance. Plant cover influenced the relative abundance of non-AM fungal communities inhabiting the roots of pulses and wheat in phase I of the rotations. The fungal community associated with wheat roots was different from the pulses’. Also the fungal communities inhabiting the roots of chickpea and pea were different. The relative abundance of Fusarium tricinctum (OTU5) was highest in pea and lowest in wheat. Fusarium redolens (OTU16) was more abundant in the roots of lentil and pea than in chickpea and wheat. Cryptococcus sp. (OTU6) was the most abundant OTU found in wheat. Additionally, pea had the highest AM root colonization levels and wheat had the lowest. Root colonization by non-AM fungi was not different between crops. Root colonization by both, AM and non-AM fungi, was higher in 2010 than 2011, which was a drier and warmer year. These results suggest that previous crop, plant cover and climate have a great influence on the abundance of fungal communities. 213 Microbial Community Structure and Activity after Long-term use of Dairy Manure and Fertilizer Reflects Soil Properties and Impacts Soil N Transformations Katarina Neufeld1, Sean Smukler1, Sue Grayston1, Shabtai Bittman2, Derek Hunt2, Maja Krzic1 1 University of British Columbia, Land and Food Systems Agriculture and Agri-Food Canada 2 Dairy manure is a valuable source of plant nutrients, yet surplus application may lead to N loss through NO3leaching and N2O emissions. Removing solids from whole dairy manure reduces the organic N and C contents, potentially improving crop N uptake, but reducing soil microbial activity compared to whole manure. The objective of this study was to quantify long term effects of contrasting nutrient applications to perennial grass on soil microbial activity and community structure, and to test relationships with soil properties and rates of N transformation. Microbial community structure and activity (biomass, phospholipid fatty acids, and hydrolyzing enzymes) and N dynamics (net mineralization and nitrification, lysimeter leachate NO3-, static chamber N2O emissions) were measured in 2013 and 2014 on a stand of tall fescue (F. arundinacea) established in 2002 at the Pacific Agri-food Research Centre in Agassiz, BC. Replicated plots were fertilized and harvested four times annually; treatments were: whole dairy slurry manure, separated liquid fraction, NH4NO3 fertilizer, or alternating manure-fertilizer applied over eleven years. In 2013 and 2014, plots receiving whole or separated dairy manure had higher microbial biomass (594 ± 33 and 561 ± 27mg C/kg soil, respectively) than fertilizer or control (421 ± 36 and 437 ± 37mg C/kg soil, respectively), and higher activity of cellobiosidase (C-degrading enzyme) than plots receiving no amendment (143 ± 8, 140 ± 15 vs. 85 ± 8 nmol/g soil/h). Microbial biomass C and cellobiosidase activity were positively correlated with soil C, N, and P. Fungal:bacterial ratios were higher in control and whole manure than fertilizer and liquid fraction treatments. Emissions of N2O and concentrations of NO3- in leachate were consistently positively correlated with bacterial biomarkers but not total microbial biomass. N mineralization and nitrification were not correlated with any microbial group, but were positively correlated with NO3- in leachate. Overall, microbial community structure was affected by nutrient applications, suggesting an impact on N dynamics. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluating the Efficacy of the Nitrification Inhibition Assay Method using 3, 5dimethylpyrazole in Soils that Differ in Texture and Water Content Jennifer Spence, David Burton, Bernie Zebarth, Gordon Price, Alex Georgallas Dalhousie University The soil organic nitrogen pool can provide a substantial quantity of the nitrogen required by growing crops. However, the supply of nitrogen from soil is highly variable among fields and among years, and it is challenging to predict. The ability to predict this dynamic supply of nitrogen would be of value from both an economic and environmental perspective, as approximately 40% of soluble nitrogen entering soils in Canada is lost each year to leaching and denitrification. This study investigates the use of a nitrification inhibitor as a means of simultaneously measuring the rates of net nitrogen mineralization (as an accumulation of ammonium) and denitrification (as a loss of nitrate) throughout a 28-day incubation. The compound 3, 5dimethylpyrazole (DMP) was evaluated using two soil textures (fine vs. coarse) at three water-filled pore space contents (35, 50 and 85% WFPS). Microbial activity (respiration) was assessed by measuring CO2 production in treatments with DMP and those without DMP to determine the oxygen demand in the soil during the incubation. Preliminary results suggest that DMP addition in the sandy loam resulted in essentially complete inhibition of nitrification at all water contents, whereas in the clay loam, the amount of nitrification was sufficiently small to be of limited practical consequence. 214 Growth of Timothy root and associated arbuscular mycorrhizae as affected by phosphorus fertilization in North Québec Yichao Shi, Noura Ziadi, Chantal Hamel, Julie Lajeunesse, Jean Lafond Agriculture and Agri-Food Canada The root architecture and mycorrhizal associations are important traits for enhancing plant phosphorus (P) uptake from soil. However, their response to mineral P fertilization under grasslands production is poorly understood. We assessed the effect of P fertilization on the root attributes, arbuscular mycorrhizal fungal (AMF) colonization, plant growth, and plant P concentration in grassland. This study was conducted in timothy (Phleum pratense L.) swards on a Labarre clay loam at Normandin (QC), Canada. Three P rates (0, 20, and 40 kg P ha-1) replicated three times have been applied in the spring of each year since 2010. Soil cores (0-10 cm) were collected in June 2013 after the first cut and in August 2014 after the second cut. Root morphology, AMF colonization, root and plant P concentrations were determined. Results showed that dry matter yield, root biomass, and P concentrations in the roots and plants were not affected by P fertilization. On average, dry matter yield and root biomass were 2.3 Mg ha-1 and 5.3 mg cm-3 in June 2013 and 0.4 Mg ha-1 and 2.1 mg cm-3 in August 2014, respectively. Mineral P fertilization had no significant influence on root attributes including specific root length, root surface area, average root diameter, root volume, and the percentages of fine, medium-size, and coarse roots. The hyphae, arbuscule, and total AMF colonization had no response to P application in both sampling dates. Only vesicle colonization was greater when 40 kg P ha-1 was applied than without P application in August 2014. We conclude that mineral P fertilization had no influence on the root architecture and had a limited effect on the AMF colonization in timothy swards in eastern Canada. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S9: Soil Science Education and Outreach 215 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Developing an on-line nutrient management planner-training program in Atlantic Canada Web-based Educational Tool for Forest Floor Description and Humus Form Classification David Burton Maja Krzic1, Darrell Hoffman1, Margaret Schmidt2, Samson Nashon3, Les Lavkulich1 Dalhousie University 1 In recent decades greater focus has been placed on nutrient management in Atlantic Canada to improve economic returns and reduce environmental impacts. An Atlantic Nutrient Management Planner Training program was initiated in 2003 and was delivered using workshops organized on an as-needed basis. To provide (i) more timely access, (ii) offer to a broader audiences including undergraduate students and professions and iii) to initiate and Atlantic forum for ongoing discussion of nutrient management issues in Atlantic Canada, the Nutrient Management Planner Training program has been adapted for a blended learning approach. We have integrated undergraduate student training in soil fertility and industry training in nutrient management into a single course to serve multiple audiences. This approach involves the delivery of theory and practice through a series of modules utilizing experiential learning where possible as well as a weekend workshop for face-to-face interaction. The presentation will discuss some the pedagogical, administrative and technical opportunities and challenges to the on-line delivery of a nutrient management course to multiple audiences. 216 University of British Columbia, Land and Food Systems Simon Fraser University 3 University of British Columbia, Education 2 Global issues are putting an increasing demand on world soil resources, highlighting the need to provide soil science education to the next generation of land managers. The forest floor is an important carbon sink and provides habitat for the majority of the soil microbial community that decomposes organic matter. Changes in forest floors could serve as early indicators of ecosystem changes due to pollution, changes in climate, or management practices. Web-based learning (WBL) is creating new opportunities for postsecondary education through multimedia enrichment of material, flexibility of time and place along with increased learner control over what material is accessed and the pace of review. The objectives of this study are to: (1) develop a web-based educational tool combining classroom-based teaching with web-based learning, to teach forest floor description and classification of humus forms and (2) evaluate the tool’s effectiveness in teaching students to describe forest floors, classify humus forms and understand associated ecological processes. The forest floor educational tool will give students access to streaming videos, maps, text, photos, graphs, and web links. Using WBL to present material will address the necessity of repetitive visual observations in the description of the forest floor and identification of humus forms. The tool is currently being developed in conjunction with a lab section in the Introduction to Soil Science course at the University of British Columbia, Vancouver by a team of scientists, videography and digital media experts. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 EasyGrapher v4.6: Software for Data Visualization and Statistical Evaluation of the DSSAT v4.x model and the CANB v4.0 Model Investigating Student Perceptions of Academic and Professional Learning Experiences in a Field-Based Course Jingyi Yang, Craig Drury Thomas Yates1, Kyle Hodgson2, Greenhouse and Processing Crops Research Centre, AAFC 1 University of Saskatchewan, Soil Science Golder Associates Ltd. 2 Crop simulation models are process-based and can provide very detailed outputs of the simulated crop and soil processes. However, analyzing the outputs is challenge. EasyGrapher (EG) is a graphical and statistical software program designed for the DSSAT v4.x Cropping System Models, and it also supports graphing and data management of Canadian Agricultural Nitrogen Budget (CANB) model. EG allows users to manipulate hundreds of graphs within minutes and calculates evaluation statistics. Specifically, EG v4.6 can support 16 outputs of DSSAT v4.6 to: (1) create time-series graphs and display measured data in the simulation graphs; (2) graph simulated data against measured data and (3) calculate evaluation statistics (RMSE, E, EF and d). EG-CANB can support outputs of CANB v4.0 to create bar plots for spatialseries graphs in various scales. The EG program has the potential to carry out graphic and statistical tasks for other models. Graphic and statistical evaluation examples were illustrated using field dataset collected from our experiments in Canada and China, as well as dataset resided in the DSSAT software. 217 One intent of field-based courses in soil and environmental science based programs like Renewable Resource Management (RRM) is to deliver job relevant skills such as soil classification and plant identification. Typically these skills are delivered by an academic even though the majority of these students will go on to exercise them professionally under the supervision of professional soil scientists and ecologists. Teaching collaborations between academic and professional soil scientists and ecologists can potentially enhance the learning experience by delivering the same skills in a context more relevant to a student’s post-degree expectations. In the 2013 and 2014 delivery of RRM 301-Field Course in Renewable Resource Management, the course curriculum was altered to include learning experiences led by professionals in addition to those led by the academic instructor. Students were subsequently surveyed for their perspective on three learning experiences: soil classification and plant identification in the Nisbet Forest with a member of faculty, Department of Soil Science, University of Saskatchewan; vegetation survey in Prince Albert National Park, Saskatchewan under the direction of Parks Canada ecologists; training session on right-of-way pre-assessment at the North East Swale grassland, Saskatchewan under the direction of a Senior Agrologist with Golder Associates Inc. We were interested in knowing in what way the students valued each learning experience and if they saw a difference between them in terms of how it related to their post degree expectations. The results indicated that students found value in each experience for different reasons. There was a clear indication that involving professionals in the delivery of the field course allowed students to see their learning in the context of a post degree career instead of only within the context of the course. Academic-professional teaching collaborations in this setting have potential to significantly enhance student engagement. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S11: Wetland Soils in a Changing Climate 218 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Examining the fate of carbon among wetlands reclamation trials in Fort McMurray, Alberta Detecting soil drainage and compaction issues by ground penetrating radar in Histosols Claire Hobson1, Graham Clark1, Elyn Humphreys1, Sean Carey2 Jonathan Lafond, Awa Mbodj, Jacynthe Dessureault-Rompré, Jean Caron, Silvio Gumiere 1 Carleton University, Environmental Sciences McMaster University, Geography and Earth Sciences 2 Peatland ecosystems have the potential to act as sinks and sources for greenhouse gases such as carbon dioxide (CO2) and methane (CH4). Oilsand mining near Fort McMurray, Alberta involves the removal of peatlands and other northern boreal ecosystems. Producers are required to reclaim disturbed land. An examination of carbon fluxes within reclaimed wetlands is necessary in determining effective reclamation strategies. The purpose of this study was to assess the CO2 and CH4 exchange between constructed wetland trials and the atmosphere. Two treatments were studied: stockpiled peat mixed with mineral soils and relatively undisturbed live peat transplants. Chambers were used to measure CO2 and CH4 exchange from unvegetated plots throughout the growing season from 2012 through 2014. Emissions of CO2 and CH4 were greatest for the live peat. CO2 emissions increased with drying while CH4 emission decreased. The relationships between these emissions and available nutrients including nitrogen and sulfur in the soils will be explored. 219 Université Laval, Départment des sols et de genie agroalimentaire Soil compaction is a major issue in conventional agriculture, with millions of hectares of fertile land degraded in North America and Europe. Affected areas can strongly modify the hydrology of hillslopes and watersheds by reducing the infiltration capacity of the soil. Information on compaction and hydrology is crucial for developing advanced modeling tools to allow experts to prevent damage and rehabilitate affected areas. Ground penetrating radar (GPR), a technology used in archeology and geophysics, has been used here to detect compaction layers causing drainage problems in agricultural fields. This technic involved a transmitter and a receiver in a fixed geometry using radio waves over the soil surface to detect reflections from subsurface features such as tile drains. In this work, we performed a GPR survey over Histosols under crop production in Québec, Canada. An experimental part of a poorly drained field had been re-drained in 2011. Two drains were installed using a drainage-mole. Drain sections were either (1) filled with surface soil (method F) to recreate a textural continuity from drain to surface, or (2) let opened as growers usually do (method C) allowing the soil to almost reinstate its profile. The GPR surveys were done during February 2015, almost four years after the experimental site installation. Results indicated that GPR images from the subsoil were quite in agreement with pedological profiles performed in these areas during the end of summer 2014. The subsurface compacted layer was identified with a centimetric precision within the GPR images. This compacted layer was known to be present and causing perched water table. Also, the drainage method F was detectable over a drain where the surface soil filling was found to be less humid than adjacent soil. GPR images allow detecting compaction and water infiltration problems without digging hundreds of holes in the field. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil organic carbon in riparian ecosystems and the potential of C reservoirs in a context of environmental sustainability Diane Saint-Laurent1, Vernhar Gervais-Beaulac2 1 Université du Québec à Trois-Rivières (UQTR) Université Laval formation and in organic carbon stocks, and also on the other nutrients. If the current hydrological conditions are maintained (an increase in the flood rate for instance), one can expect a diminution of organic C and nutrient storage depletion that could restrict the regeneration of forest stands and the vitality of riverside ecosystems. 2 Soil organic carbon (SOC) and soil total nitrogen (STN) play a key role in pedogenic processes and contribute to soil fertility and carbon pool. The floodplain areas usually are important storage zones of soil organic carbon. In flood zones, little is known about the processes associated with the development of alluvial soils subject to frequent flooding, in particular with respect to the accumulation of biomass on the ground, concentrations of SOC and soil nitrogen. We have compared concentrations of soil organic carbon (SOC%) and other soil properties in different riparian forests located in a southern Québec watershed. We used also a paired-site approach to determine the concentration of SOC and other properties (e.g. nitrogen, pH, cation exchange capacity (CEC), phosphorus, potassium and grain size particles) in link with flood recurrence intervals. Two specific flood-risk zones, i.e. Frequent flood zones and Moderate flood zones (20-year vs 100-year flood) in connection were considered to evaluate the variability of different soil properties. Sampling sites located outside of the two flood-risk zones were also selected for a crosscomparison. The results show that alluvial soils subject to frequent flooding have a lower concentration in soil organic carbon (SOC%) and soil total nitrogen (STN%) than soils in non-inundated zones. The average values obtained for surface horizons (0-20 cm depth) range from 1.79 ± 0.83 to 2.16 ± 1.28 (SOC%) and from 0.14 ± 0.05 to 0.17 ± 0.07 (STN%) for soils in frequent flood zones (FFz), while for soils in no-flood zones, the values range from 5.17 ± 2.99 and 3.82 ±1.88 (SOC%), and from 0.30 ± 0.28 to 0.24 ± 0.10 (STN%). The tstudent tests conducted among the various zones confirm this trend of a depletion in soil organic carbon and soil total nitrogen for the soils found in the frequent flood zones. The absence or virtual absence of litter in frequently flooded areas contributes to decreasing the input of organic matter in the surface horizons and progressively reduces SOC concentrations. A crucial external forcing factor for SOC and soil fertility related to riparian vegetation is the amount and quality of the litter input. The organic carbon and nitrogen of the added litter is a very sensitive parameter. A lower concentration of nutrients was also noted for the soils affected by floods. Soil acidity is higher in the no-flood zones, which could be attributed to the acidifying inputs of the litter, which is more abundant and better formed (LFH layers) in the no-flood forest zones. Variations in the hydroclimatic conditions (e.g. increase of precipitations and floods), have an impact on the soil 220 Impact of Short Rotation Willow on Prairie Wetland Soil Hydrology and Salinity Md Shayeb Shahariar1, Raju Soolanayakanahally2, William Schroeder3, Angela Bedard-Haughn1 1 University of Saskatchewan, Soil Science Saskatoon Research Centre, AAFC 3 Agroforestry Development Centre, AAFC 2 The Prairie Pothole Region (PPR) contains millions of small wetlands that serve the important hydrologic function of storing soil moisture and recharging ground water. Water balances of these PPR wetlands are very sensitive to surrounding riparian land management. The potential effects of land use changes on the water balance of these wetlands are an important concern for agriculture, management of water resources and wildlife habitat in this region. Evapotranspiration by riparian vegetation is the dominant pathway of water loss in this semi-arid region. High transpiration rate of willow vegetation that are commonly present in the riparian zone of uncultivated PPR wetlands are known to lower groundwater levels and contribute to the accumulation of secondary carbonates in the soil profile (i.e., willow ring soils). However, it is not known whether fast growing, Short Rotation Willow (SRW), grown for agroforestry or bioenergy, would have a similar impact. The impact of SRW cultivation in the riparian zones of PPR wetlands on groundwater table fluctuations and changes in soil salinity levels at different depths along transects was compared to other land use practices (annual crop and pasture) in a field experiment at Indian Head, Saskatchewan during the growing season of 2014. The results will have important implications in future environmental use of SRW as a land use practice in the marginal land of prairie wetlands as well as in planning wetland management and conservation in this region. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Variability of peat soil characteristics in boreo-nemoral environment (Latvia) Inese Silamikele1, Janis Krumins2, Maris Klavins1 1 University of Latvia, Biology University of Latvia, Environmental Science 2 The research of mires is an integral part of global change studies. The territory of Latvia is located in an ecologically sensitive area between the oceanic and continental climate zones. Geobotanically Latvia belongs to the boreo-nemoral vegetation zone. The total area covered by peat soils in Latvia is 6900 km 2, about half of them are fen peat soils. Large part of Latvian mires have been drained and further peat accumulation is suspended, severely restricted or peat accumulation is very slow. To evaluate the possibilities and perspectives of peat use and to study environmental changes and the contamination flow in a historically long period of time the characterization of the distribution and concentration of metallic and nonmetallic elements in peat is important. The aim of the present study is to analyze peat properties, elemental composition, trace and major element composition as well as relations between biota of fens and peat composition. The chemical composition of various peat types in Latvia is studied with main focus on raised bog peat. In mire studies bogs and fens however should be viewed as unified systems (not only the upper layers, but including full peat profiles), the characterization of metallic and non-metallic element accumulation in selected bogs and fens has proved that the bottom part of peat profile is heavily affected by the supply of chemical elements with groundwaters, and the intensity of element accumulation is determined by the peat composition and the geomorphological conditions of the bog or fen. Climate change has a significant impact on peat soil formation; it is increasing the mineralization degree of peat soil. Mire formation is increased due to a higher water supply by both natural succession and melioration systems functionality. 221 Nutrient dynamics along drainage ditches under recent, medium and long-term drainage in the Black soil zone of southeastern Saskatchewan Zhidan Zhang, Robin Brown, Angela BedardHaughn University of Saskatchewan, Soil Science Agricultural drainage ditches are widely used in humid regions throughout the world. Ditches improve drainage and reduce in-field flooding, but may also assist in minimizing off-site nutrient losses via nutrient cycling and retention. Therefore the objective of this study was to determine whether within-ditch nutrient dynamics change as a function of duration of drainage. In fall 2014, 37 soil samples were collected along nine drainage ditches from the Black soil zone in southeastern Saskatchewan; the age of ditches ranged from 7-50 years. Soil cores were collected from midditch and ditch-slope at regular intervals along a 100m length; cores were segmented into 3 depths (0-15, 15-30 and 30-60 cm) for nutrient analyses, including organic carbon (total and water-extractable), available N pools, potential nitrogen mineralization/nitrification, and phosphorus sorption/desorption. Selected results will be presented. Overall, this study aims to improve our understanding of potential benefits and risks of nutrient storage and release under drained conditions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S12: Proximal Soil Sensing 222 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Impacts of subirrigation and low water potential on soil salinity and its effects on cranberry development Comparing logistic model trees and multinomial logistic regression for the prediction of soil development in BC Marie Élise Samson, Josée Fortin, Jean Caron, Steeve Pepin Jin Zhang1, Brandon Heung1, Derrick Ho1, Anders Knudby1, Chuck Bulmer2, Margaret Schmidt1 Laval University, Agricultural and Food Sciences 1 Recent research on soil tension in cranberry production have identified matric potential threshold (-4 to -7 kPa) in order to optimize yields while minimizing water use. However, precision irrigation in cranberry production often leads to a decrease in soil water content. Moreover, some recent studies suggest that subirrigation in cranberry production could actually reduce the use of water and irrigation costs while maintaining optimal yield. However these new recommendations could have some considerable impacts on the movement of mineral fertilizers in the soil due to the upward water flow combined with considerably dry soil conditions. Since this could eventually lead to salinity problems in the root layer, these irrigation systems should be put to further investigation. The objective of this study was to determine a soil electrical conductivity threshold in cranberry production and to evaluate the effects of different irrigation types on the ions profile in a sandy matrix and its impacts on plant development. To achieve that, cranberries were collected in a sandy field and placed in a greenhouse under controlled conditions. The 60 bins containing the plants and their original matrix were distributed in four blocks, each containing eight treatments obtained from two different irrigation systems (sprinkler and subirrigation with -6.5 kPa in the root layer) and four different salinity treatments obtained with different doses of K2SO4. The experimental units were continuously monitored for matric potential, water content and electrical conductivity measurements. Photosynthesis, pressionvolume curves, growth and yield measurements were also performed. Although the various treatments produced an increase in soil electrical conductivity, our data suggests that irrigation system had little influence on soil salinity. However, this study also shows that salinity could be a variable to consider in cranberry production since the threshold for optimal yield could be lower than expected. 223 Simon Fraser University, Geography British Columbia Ministry of Forest Lands and Natural Resources 2 Both linear and tree-based models are commonly used to predict categorical soil variables with good result; however, a hybridization of these two types of models has yet to been evaluated. The objective of this study is to evaluate the hybridization of a multinomial logistic regression (MLR) model with a hierarchical tree structure from tree-based model. Predictions were made at a 100 m resolution for the Lower Fraser Valley, BC. Soil development and environmental variables were extracted from conventional soil survey data. Environmental variables were used to represent topographic indices, climate averages, and vegetation coverage to calculate predictive results. MLR (liner model), CART(tree-based model), and a logistic model tree (hybrid model) were used to identify the relationship between soil development and environmental variables. The hybridization is unique in that the model is now able to capture nonlinear relationships between predictor and observed variables. The relationships were then used to predict soil great groups for unsurveyed locations in the Lower Fraser Valley. Validation was completed using data from 262 points obtained from legacy soil survey data. The accuracy for MLR, CART, and a logistic model tree were 42.4%, 40.1%, and 51.9% respectively. Hybridization of linear regression and decision tree models increases the prediction accuracy of the spatial distribution of soil development. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 A new model to predict soil pH at depths in agricultural fields Yakun Zhang, Asim Biswas McGill University, Natural Resource Sciences Soil pH controls the availability of majority of the plant nutrients, if not all, and determines the growth environment for plant roots. While it is easy and convenient for surface soil layers, sample collection from subsurface layers and subsequent measurement of pH is challenging and time intensive. Some models (depth functions) have been used to predict soil attributes at continuous depths. Those models are individually fitted to soil profile data to derive soil attributes continuously with depth and lack the generality. Additionally, the functions used are often deficient of physical explanation. This paper proposes a new model to predict pH for whole soil profile. Soil properties including pH are often similar within the plough layer from mixing during tillage and other agricultural operations. Similarly, soil pHs at depth are often very uniform below the root zone leaving a transition zone from the bottom of the tillage layer to the bottom of the root zone, where pH changes gradually. Keeping this physical condition in mind, a closed form equation (model) was developed similar to a logistic curve. The model has 4 parameters (with option to be two) including minimum value, maximum value, a hillslope parameter representing steepness of the curve and the inflection point representing almost the midpoint of the transition zone. A total of 34 soil cores up to about 1.1 m were collected from an agricultural field from Macdonald farm of McGill University and sampled at every 10 cm and analyzed for pH in laboratory. A total of 24 cores were selected to calibrate and 10 cores to validate the model. The results were compared with the commonly used polynomial regression and equal area spline functions using same set of samples. The new model performed better with physical explanation compared to the commonly used ones. 224 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S13: Spatial and Temporal Dynamics of Soil Processes and their Interactions at Multiple Scales to Study Complex Soil Systems 225 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 The Relationship between Ion Exchange Membrane (PRS Probe) Measurements and Extractable Nutrient Concentrations Interactions between the microbial processes and nutrient transformations in beach sediments under dynamic flow regimes Lindsey Andronak1, Eric Bremer1, Kishari Sooriya Arachchilage1, Jeff Schoenau2 Avid Banihashemi1, Fereidoun Rezanezhad1, Radmila Kovac2, Danny Oh1, Christina Smeaton1, Clare Robinson3, Philippe Van Cappellen1 1 Western Ag Innovations University of Saskatchewan 2 Plant Root Simulator (PRS) probes are widely used for in situ monitoring of soil nutrients in a wide range of ecosystems. Common questions we receive are: How can I convert my PRS probe results into concentrations and how does this measurement compare with other soil tests? Although PRS-probe measurements are often strongly correlated to extractable soil nutrient measurements, the relationship is not constant or linear due to the different factors that influence these two types of measurement. We evaluated a range of studies to clarify controlling factors and facilitate appropriate comparisons between measurements. The main factor contributing to differences between PRS probe and extraction measurements is soil ion mobility. Short-term PRS-probe measurements of mobile soil ions such as nitrate and sulfate are often strongly correlated to extraction measurements, but the quantitative relationship varies with soil moisture and duration of PRS probe exposure. In contrast, PRS-probe measurements of immobile nutrients such as NH4-N, P and K are often relatively insensitive to duration of burial, but are not as strongly correlated with extraction measurements (which also vary widely and are not consistently related). Ion interactions may influence PRS measurements to a greater extent than extraction measurements. The two methods of monitoring soil nutrients often complement each other, and can often be compared with appropriate consideration of method and context. 226 1 University of Waterloo, Ecohydrology Research Group Cornell University, Plant Research 3 University of Western Ontario, Civil and Environmental Engineering 2 Shoreline sediments act as a reservoir for fecal contaminants with E. coli concentrations often orders of magnitude higher than in adjacent shallow waters. The process by which E. coli accumulates and persists in the sediment and how it is affected by nutrient availability is unknown. In this study, we used an automated water table fluctuating column system to improve understanding of the interactions between the microbial processes and nutrient transformations and how they are influenced by different environmental conditions and dynamic flow regimes. Undisturbed sediment cores were collected from the Burlington beach in Ontario and were inserted into the columns. The water table fluctuation in the column system was designed to follow the dynamic flow regimes observed at the beach sites to quantify how they affect bacteria transport, distribution and survivability, and the biogeochemical zonation and nutrient transformations near the surface water interface (SWI). A naturally occurring nalidixic acid resistant E. coli strain was inoculated into the columns. The bacterial transport was studied by one time inoculation of 1µm fluorescent microspheres as bacterial surrogates. E. coli was enumerated from sediment samples (< 1 gr) collected along the column depths using a mini-core sampler and was analysed using DNA-based quantification technique (qPCR) over a period of one month. Changes in pore water composition were monitored by collecting water samples from different depths of the columns using micro-Rhizon samplers. At the end of the experiment, the columns were sliced and analyzed for microspheres, E. coli concentrations, and nutrients in the solid phase. Furthermore, the microsphere data was used to evaluate a 1-D colloid transport model simulation under the transient water flow in variablysaturated media. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil Phosphorus Distribution under Two Contrasting Grasslands (2 and 10 yrs old) Effect of long-term tillage regimes on topsoil pore network dynamics and field saturated hydraulic conductivity Athyna Cambouris, Isabelle Perron, Noura Ziadi Soil and Crops Research and Development Centre, AAFC Under old grassland production, multi-year of manure application can result in soil phosphorus (P) enrichment which could increase the agricultural contribution to eutrophication, as a result of surface runoff or leaching. This issue was addressed by the comparison of the vertical and spatial P distribution under two contrasting grasslands. Two commercial fields, young grassland (Y; 2 years; 2.35 ha) and old grassland (O; 10 years; 2.47 ha), both fertilized by organic fertilizer (i.e. pig and beef manure) were chosen to evaluate the spatial P variability at two depths (0-5 cm and 5-20 cm). Both fields were Podzol moderately well drained (Beaurivage soil series). Soil pedological and properties (texture, drainage, etc.) maps were extracted from the detailed soil map (1: 20k). In the fall 2013, soil sampling was conducted using a triangular grid design with a sampling interval of 16 m. All soil samples were analyzed for P as extracted by Mehlich-3 (P-M3), soil pH, and total carbon and nitrogen. There was a significant effect of the management crop (Y vs O) and depth (0-5 cm vs 5-20 cm) on soil P-M3, there was also a significant interaction between management crop and depth. In both profiles, P-M3 was significantly lower (30 vs 93 kg P ha–1) under Y grassland than under O grassland (65 vs 133 kg P ha–1). The long-term buildup of soil P of the old grassland can have environmental consequence. Excess soil P can move into surface water through runoff and soil erosion and into groundwater by leaching through desiccation cracks. 227 Yu Cao, Richard Heck, Gary Parkin, Mila Maric University of Guelph, Environmental Sciences Soil porosity is an essential factor that influences aeration, permeability, water infiltration, solute dispersion, etc. Tillage is a physical practice that directly alters the pore structure of topsoils, hence exerts pronounced effect on pore-related characteristics and functions. This study was carried out on the long-term diversified tillage plots on silt loam soil located at the University of Guelph’s Elora Research Station and the cropping system is cornsoybean. The tillage regimes selected for this study were zero-tillage, fall mouldboard plough with spring cultivate/pack, fall chisel plough with spring cultivate/pack, spring mouldboard plough with cultivate/pack, and spring tandem disc (2x). From each treatment, intact soil cores were sampled at pre-plant, mid-season and post-harvest periods to quantify the pore characteristics using X-ray CT (computed microtomography); meanwhile, infield infiltration rates were measured using fall-heading method per month during the identical agronomical periods. The objectives are to quantify the pore-related characteristics (pore size distribution and connectivity) by X-ray CT and field saturated hydraulic conductivity (Kfs) based on field infiltration rate. The study is supposed to figure out that whether the long-term tillage regimes will exert significant effect on topsoil pore network dynamics and field saturated hydraulic conductivity; also evaluate and optimize the methodology regarding the quantification of soil pore network using X-ray CT technique. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Interaction of nitrogen fertilizer application, crop rotation, and tillage system on longterm soil carbon and nitrogen dynamics Does Row Width and Harvest Date Influence Sugarbeet (Beta vulgaris L.) Nitrogen Requirements? A.H. DeBruyn1, I.P. O’Halloran1, J.D. Lauzon2, and L.L. Van Eerd1 Katelyn Congreves, Dave Hooker, Laura Van Eerd University of Guelph Ridgetown Campus 1 School of Environmental Sciences, University of Guelph School of Environmental Sciences, University of Guelph 2 While the influence of climate, crop rotation, and tillage on soil C sequestration and soil quality has been well documented, there remains considerable uncertainty in the response of soil C and N dynamics to the increase in the use of nitrogenous fertilizers. Using a long-term (11 yr) experiment on a clay loam Orthic Humic Gleysol at Ridgetown, Ontario, we evaluated the impact and interaction of crop rotation (continuous corn (CC), cornsoybean-wheat (C-S-W), and corn-soy (C-S)), tillage (conventional and no-till), and N fertilizer application (0 vs 100 kg N ha-1 yr-1 to corn and 80 kg N ha-1 yr-1 to wheat) on soil organic C and total N in the 0-120 cm depth rangeUnder conventional tillage, the application of N fertilizer enhanced soil organic C by 10 to 18 Mg C ha-1 and total N by 1.1 to 2.6 Mg N ha-1 within the 0120 cm profile for CC and C-S-W rotations, respectively, but not in the C-S rotation. Nitrogen fertilizer had less influence on soil attributes for systems grown with no-till compared to conventional tillage. Our results suggest that soil mixing due to tillage can enhance the effect of N fertilizer on soil organic C and total N sequestration in the 0-120 cm profile, possibly leading to more fertile soil. However, the effect and interaction of N fertilization and tillage on soil attributes within deep soil layers (up to 120 cm) was highly dependent on the crops produced. We present the first paper to synthesize soil and crop data to show that winter wheat in crop rotation contributed to greater SOC and TN sequestration and higher crop yields. Therefore, our study furthers the agronomic knowledge and understanding of how winter wheat influences soil biogeochemistry and crop production. 228 The response of sugarbeet (Beta vulgaris) to N fertility is well known, but the influence of recent changes in production practices is not. Given that N requirements of sugarbeet may be influenced by higher plant populations and/or earlier harvest dates, experiments at two locations in Southwestern Ontario were established in 2013-14 in a randomized complete block design with four replicates. Main plot treatment was five N rates (0-202 kg ha-1) of pre-plant incorporated calcium ammonium nitrate with a split-plot of row width (57 vs. 76 cm) of 6 m by 10 m. Two rows 4 m long were harvested in mid-September and late October. In both years, there were no two-way or three-way N rate interactions with harvest date or row width on root yield and recoverable white sucrose (RWS) content (Mg ha 1 P>0.05); therefore, growers do not need to modify pre-plant N fertilizer rates based on these management practices. In both years, early harvest had a 21-36% and 35-40% decrease in root yield and RWS content, respectively, compared to late harvest (P<.0001). In 2013, compared to wide rows, narrow rows had 36.1 12.9, and 5.5% higher root yield ha-1, RWS content and RWS concentration (P<0.05), respectively, but there was no difference in 2014 (p>0.05). Pooled over locations, N rate positively correlated to root yield (6 of 8 site-years P<0.05, 2 site-years P<0.1) and negatively correlated to RWS concentration (7 of 8 site-years P<0.05, 1 not significant). Based on the payment program of a bonus for early harvest and high RWS, the economics of N application were evaluated based on regression equations. The mean difference of applying N fertilizer to optimize root yield vs. RWS concentration was $546 ha-1, which ranged from $-92 ha-1 to $1775 ha-1. Thus to achieve most economic returns growers must manage N fertilizer based on various external economic drivers rather than only optimizing beet yield. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Nutrients in snowmelt and rainfall-generated runoff from the clay soils of the Red River Valley, Manitoba, Canada Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic Jane Elliott1, Jason Vanrobaeys2, David Lobb3, Don Flaten3, Larry Braul2 David Grewer1, Melissa Lafrenière2, Scott Lamoureux2, Myrna Simpson1 1 1 2 2 Environment Canada Agriculture and Agri-Food Canada 3 University of Manitoba Like many other surface water bodies, the world’s tenth largest freshwater lake (Lake Winnipeg in Manitoba, Canada) is suffering from nutrient enrichment. Most nutrients entering Lake Winnipeg are transported in the Red River that flows from the USA through Manitoba to the lake. Historically discharge and nutrient loading in the Red River are greatest during spring freshet when the winter snowpack melts and infiltration is limited by frozen soils. Non-point sources in agricultural land in the watershed have been shown to make a significant contribution to the nutrient load in the river and management practices to retain nutrients on the land in the snowmelt-dominated regime are being developed and evaluated. A number of studies have examined nutrient runoff from agricultural land in the Manitoba portion of the watershed but the extensive area of clay soils on the floodplain adjacent to the river has not been evaluated. In this study we investigate the potential contribution of the clay floodplain soils to the nutrient load through direct measurement of runoff water quality relative to soil management factors. By comparison with other long term sites in the watershed, we are able to determine how the clay soils differ from previously studied soils in nutrient release and transport mechanisms during both snowmelt and rainfall-generated runoff events. This will help to determine if management practices developed for lighter-textured sloping soils in the watershed will be appropriate for the clay soils on the floodplain. 229 University of Toronto at Scarborough Queen’s University With increased warming in the Arctic, permafrost soil thawing may induce localized physical disturbances of slopes. These disturbances, referred to as active layer detachments (ALDs), redistribute soil across the landscape and potentially release large quantities of previously unavailable carbon. In 2007-2008, widespread ALD activity was reported at the Cape Bounty Arctic Watershed Observatory in Nunavut, Canada. Our study investigated organic matter (OM) composition in soil profiles from ALD-impacted and undisturbed areas. Solid-state 13C nuclear magnetic resonance (NMR) and solvent-extractable biomarkers were used to characterize soil OM. Throughout the disturbed upslope profile, where surface soils and vegetation had been removed, NMR revealed low Oalkyl carbon content. Biomarker analysis revealed relatively low concentrations of solvent-extractable compounds and along with NMR data suggests enhanced erosion of labile-rich OM in the upslope region following the ALD. In the disturbed downslope region, vegetation remained intact but the displaced mass from upslope produced lateral compression ridges at the surface. Characterization of surface horizons revealed high O-alkyl content, consistent with enrichment of carbohydrates and peptides, but low concentrations of labile biomarkers such n-alkanoic acids and monosaccharides. This suggests the presence of relatively unaltered labile-rich OM. Additionally, relatively high concentrations of longchain n-alkanes observed at the surface may indicate increased vascular plant inputs. Below the surface, Oalkyl content and overall biomarker concentrations decreased. This change in OM composition differed from the undisturbed profile and may indicate redistribution of subsurface OM via hydrological transport or as a result of compression ridge formation. However, pre-ALD profile composition remains unknown; hence nominal inputs within the downslope soil may contribute to observed decreases. The results demonstrate how ALDs can redistribute OM across the landscape, reallocating labile carbon to more accessible areas where subsequent degradation or erosion may contribute to increased carbon export from ALD-impacted Arctic soils. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluating the Impact of the Spatial Distribution of Land Management Practices on Water Erosion Uncertainty and sensitivity analysis of the DSSAT model: soil water, management and weather parameters Silvio Gumiere Wentian He 1, 2, Jingyi Yang 1, Wei Zhou 2, Craig Drury 1, Ping He 2, Zhuoting Li 1 Université Laval, Départment des sols et de génie agroalimentaire 1 Greenhouse and Processing Crops Research Centre, AAFC Chinese Academy of Agricultural Sciences, Agricultural Resources and Regional Planning 2 The spatial distribution of land management practices (LMPs), such as the use of vegetated filters, may have a strong impact on their efficiency in trapping sediments and pollutants. Distributed water erosion models help managers, planners, and policymakers optimize the efficiency of these LMPs regarding their location relative to water and sediment pathways. In this work, the authors analyzed the impact of the spatial distribution of LMPs using an existing distributed model and sensitivity analysis procedures. The distributed model that was used is a distributed single-event physically based water erosion model developed to calculate erosion rates and sediment flow for small (less than 10 km2) agricultural catchments. To measure the impact of the spatial distribution of LMPs, the authors developed a stochastic model that generates LMP locations over the entire catchment. The stochastic model has three input parameters: the density of LMPs, their downslope/ upslope location probability, and the probability density function shape controller. Because of its ability to account for the cross effects between parameters, the variance-based Sobol method was used to calculate the sensitivity of the soil loss ratio of a typical Mediterranean agricultural catchment (Roujan, southern France) to the LMP location model parameters. Three measurement points (two subcatchment outlets and the main outlet) were used to examine the spatially distributed effects of the LMP locations. The simulation results indicated that 70% of the variation of the net erosion is explained by variations in LMP density for the main outlet catchment, making LMP density the most sensitive parameter. However, the total Sobol sensitivity indices indicate a strong interaction among the three parameters when the density values are low (few LMPs are applied). Thus, although the density of the LMPs is the most sensitive parameter, their location may influence their global trapping efficiency in (real) cases where few LMPs are applied. 230 The sensitivity analysis of DSSAT outputs to uncertainty in soil water parameters, management parameters and precipitation was evaluated in wheat and maize crops located in Swift Current and Woodslee, Canada. The inputs parameters considered were: soil water drained upper limit (DUL), lower limit (LL), fertilizer nitrogen rate (FNR), plant population (PP), planting date (PD) and daily precipitation (PREC). In Swift Current, wheat yield showed high sensitive to DUL and intermediate sensitive to PREC and FNR. Wheat yield increased linearly with FNR (R2=0.96). When wheat was planted earlier 15 days than current seeding date, the yield increased by 10.3%. In Woodslee, most sensitive parameter for maize yield was PD and second most sensitive parameter was DUL and intermediate sensitive parameters were LL and PREC. The maximum maize yield was 11794 kg ha-1 and on average increased by 12.5% after delaying PD by 5 to 15 days. When maize was planted 15 days earlier, maize yield decreased by 18.6%. DUL had the most positive significant impact on biomass among the six parameters in two locations. A 20% change in DUL resulted in an average change of biomass by 13.2% and 8.8% at harvest time, respectively. DUL and PREC are the main input parameters that affect ET and SW. N leach increased with the increases of FNR in Swift Current and there was no effect on N leach in Woodslee. This study showed that sensitivity analysis method can be useful to study the importance of input parameters to various outputs in the similar process-based models. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Coarse Woody Debris Increases Soil Respiration Rates and Microbial Function but Not soil Enzyme Activity in Cover Soils for Oil Sands Reclamation Effects of input management, crop diversity, environmental covariates and terrain attributes on crop yield in the semi-arid Canadian Prairie Jin-Hyeob Kwak1, Scott Chang1, Anne Naeth1, Wolfgang Shaaf2 Taras Lychuk1, Ann Kirk2, Alan Moulin1, Reynald Lemke3, Eric Johnson2, Owen Olfert3, Stewart Brandt3, Bruce Gossen3, Julia Leeson3 1 University of Alberta, Renewable Resources Brandenburg University of Technology, Soil Protection and Recultivation 2 Characterizing and understanding microbial activity and function are important for improving early ecosystem development. Forest floor mineral soil mix (FMM) and peat mineral soil mix (PMM) are common cover soils used for land reclamation post open-pit oil sands mining in northern Alberta, and coarse woody debris (CWD) can be used as an organic matter amendment for land reclamation. We studied the effects of CWD on soil microbial activity and function such as soil respiration rate, microbial community-level physiological profile, and enzyme activities in two cover soils, FMM and PMM. This experiment was conducted with a 2 (FMM vs PMM) × 2 (near vs away from CWD) factorial design with 6 replications. The study site was established and aspen CWD was placed on each plot between November 2007 and February 2008. Soil respiration rate measurements and soil sampling were conducted within 5 cm from CWD and more than 100 cm away from CWD. Soil respiration rates were measured in July, August and September 2012 and 2013. Soil microbial community-level physiological profile and enzyme activities were measured in July, August and September 2013 and 2014. Soil respiration rates were greater in FMM than in PMM (p < 0.01) and CWD application increased soil respiration rates (p < 0.05), especially in FMM. Soil respiration rates were positively related to microbial biomass (p < 0.01) and soil temperature (p < 0.01). Microbial community function was higher in PMM than in FMM (p < 0.05) and were increased by CWD application (p < 0.05). Soil enzyme activities were greater in FMM than in PMM (p < 0.05); however, CWD application did not affect enzyme activities. Soil microbial and enzyme activities were mainly affected by cover soil type; soil respiration and microbial community function were also affected by CWD. We conclude that CWD application enhanced microbial activities and function that would increase nutrient cycling and improve ecosystem function; therefore, CWD application should benefit early ecosystem development in land reclamation. 231 1 Brandon Research Centre, AAFC Scott Research Centre, AAFC 3 Saskatoon Research Centre, AAFC 2 Farmers in the Canadian Prairies have the option to reduce inputs and diversify crop rotations to reduce their reliance on fertilizer and pesticides. The 19-year Alternative Cropping System field experiment was conducted from 1994 to 2013 at Scott, SK to assess the effects of input intensity and diversity of crop rotations on environmental and economic sustainability. In addition to the effects of input and diversity, the impacts of environmental covariates such growing season precipitation (GSP), growing degree days (GDD), and terrain attributes were assessed on the yield of spring wheat, barley, and canola. The experiment was a four replicate split-plot with main plot treatments consisting of three levels of inputs [organic (ORG), reduced (RED), and high (HI)] and sub-plots comprised of three levels of cropping diversity [low (LOW), diversified annual grains (DAG), and diversified annual perennial (DAP)]. All crop rotations were 6 years in length. Input, diversity, environmental covariates and terrain attributes significantly affected crop yield. Crops grown in the HI-DAG, HI-LOW and RED-DAG, RED-LOW rotations produced higher yields compared to all other combinations of input and diversity. Yield was lowest in ORG input system due to nitrogen deficiency and in part due to increased weed competition. Yield was highest in the HI and RED systems. April, June, July GSP and July GDD were highly correlated with crop yield followed by the effects of input and diversity, depending on the crop. Terrain attributes explained 8 to 45 percent of variation in wheat yield depending on weather conditions during the year. The impacts of fixed effects such as input and diversity on crop yield can only be assessed if variability due to environmental covariates such as weather and terrain attributes are included in the analysis. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Testing effectiveness of the Environmental Policy Integrated Climate Model on Predicting Wheat, Barley, and Canola Yield in the Canadian Prairie Taras Lychuk1, Alan Moulin1, Reynald Lemke2, Eric Johnson3, Owen Olfert2, Stewart Brandt2, Roberto Izaurralde4 1 Brandon Research Centre, AAFC 2 Saskatoon Research Centre, AAFC 3 Scott Research Centre, AAFC 4 University of Maryland, Geography Farmers in Canadian Prairies have the option to move from conventional high-input production involving one or two annual grain crops to more diversified and extended cropping systems with reduced input and organic management farming approaches. The Alternative Cropping System (ACS) field experiment was conducted from 1994 to 2013 at Scott, SK to assess the potential impact of agriculture on sustainable production and soil and environmental quality in the region. The Environmental Policy Integrated Climate (EPIC) model was updated with relevant weather, tillage, and crop management operations from the ACS study at Scott. The model was validated with annual and long-term yield data for wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and canola (Brassica napus L.). Simulations with EPIC were similar to long-term yield trends for all three crops. However, model output was poorly correlated with annual variations in crop yields. This was primarily due to (1) soil variability and micro-topography at the research site, (2) significant variation in precipitation rates and temperatures relative to region normals, (3) extreme weather events like hail which excessively damaged crops and (4) overestimation by EPIC of mineralized N under low-nitrogen input systems. The R2 values varied between > 0.60 for long-term yield predictions, and < 0.50 on an annual basis. The EPIC model should be adjusted with respect to N cycling and parameters that control soil hydrology and water use by plants. Overall, EPIC replicated effects of agricultural input systems and rotations on long-term crop yield. The model may be used by researchers and scientists as a long-term decision tool on agricultural productivity and sustainability in the Canadian Prairie. 232 Interaction or a common entry: Soil organic carbon in soil water content measurement Hida R. Manns1, Aaron A. Berg1, Ralph C. Martin2 1 2 Department of Geography Plant Science, University of Guelph, Guelph, ON, Canada In agriculture, the surface soil interface is a unique region of soil hydrology where air, plants, litter, soil organic matter (SOM) and sediment interact. The small physical size of the A horizon does not reflect its relative influence on both hydrological (division of runoff and infiltration) and biological (plant respiration) functions on vast scales. The role of SOM in agriculture is growing with interest in crop and soil sustainability. The association of soil organic carbon (SOC) as a major (58%) portion of SOM is attributed with increased water holding capacity resulting in plant productivity improvements. This presentation will discuss current data analysis on multiple scales that supports the hypothesis that SOC and soil water content (SWC) are highly correlated variables at specific times in the surface layer of agricultural soil. SWC data from the ground and aerial sampling of the SMAPVEX12 (Soil moisture active passive) satellite prelaunch algorithm development campaign found high correlation between SOC, SWC and soil texture over all wetness ranges in the top 5 cm of soil over 50 agricultural fields covering 25 km2 of southern Manitoba. Data from Ontario agricultural soils at the Elora Research Centre demonstrated a similar correlation between SOC and SWC in intensive field sampling of grain fields. A proposed model to capture the correlation and feedback process between SOC and SWC is presented. Further work to substantiate the strengths and limits of the relationship between SOC and SWC may be beneficial for model predictions of SWC for remote sensing, agriculture, hydrology and ecosystem function. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Water footprint assessment of crop production in Canada using a Canadian water budget model Banded vegetation effects on soil water storage and temperature in Jornada Basin, New Mexico Myra Martel1, Roland Kröbel1, Leila Hrapovic1, Henry Janzen1, Brian McConkey2, Aaron Glenn3, Henry Wilson3 Savitoz Sidhu1, Curtis Monger2, Asim Biswas2 1 Lethbridge Research Centre, AAFC Semiarid Prairie Agricultural Research Centre, AAFC 3 Brandon Research Centre, AAFC 2 Water scarcity and declining water quality have become global issues of concern over the past few decades. As in other countries, Canada’s freshwater supply, especially in the semi-arid region of the Prairies, is threatened by the impacts of rapidly growing population, climatic variability, and climate change. This consequently tightens the competition on water use among major water users such as thermal power generation stations, households, industries, and agriculture. Although agriculture is not the largest water user in Canada, it is by far the greatest net consumer, according to a study, for using almost 70% of the water it diverts (where 85% of it is used for irrigation). Thus, this study aims at assessing the water footprints of the major crops in Canada. Water footprint is a relatively new indicator for water use and a very useful tool for producers as they explore options for improving water use efficiency and water sustainability. A newlydeveloped water budget model is used for this purpose. The model takes into account the important components of water fluxes (i.e. evapotranspiration, precipitation, irrigation, runoff, and drainage) that flow through the soil-plant-atmosphere continuum. The water footprint estimates will be presented during the conference. 233 1 McGill University, Natural Resource Sciences New Mexico State University, Plant and Environmental Sciences 2 Banded vegetation patterns are prominent on the distal San Andres piedmont slopes in Jornada Experimental Region (JER), New Mexico and are typically composed of grass, dune, and bare zones each with unique soils. Knowledge of these patterns and their impact on soilvegetation relationships could help in developing fundamental understanding on ecosystem functions involving plant-soil-climate in these regions. In this study we seek to examine the effect of banded vegetation on soil properties in relation to climatic factors like precipitation. Experimental data for the year 2010 from Soil Climate Analysis Network (SCAN) site at JER operated by the Natural Resource Conservation Service (NRCS) was used to compare soil water storage and temperature at five different depths across these vegetation patterns. Three dimensional contour plots were used to present time and depth distribution of soil water storage and temperature and to study legacy effects of precipitation events on soil water storage and temperature. Mean annual water storage in soil profile under grasses was 6.25 cm which was 39 and 70% higher as compared to those under bare soil (3.82 cm) and dunes (1.87 cm), respectively. Mean annual soil profile temperatures were 17.6°C, 16.8ºC and 18.7ºC for grasses, bare soils and dunes, respectively. Vegetation cover, improved soil structure by addition of more organic matter, coupled with higher water infiltration through macro pores and deeper root penetrations might have resulted in higher soil water storage in grasses. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Delineation of Fe-oxides Pedofeatures in Thin Section of Hydromorphic Soils Scenario Analysis of Canadian Farming System to Residual Soil N using a CANB v4.0 model Tian Tian, Richard Heck Jingyi Yang1, Craig Drury1, Ravinderpal Gill2, Xueming Yang1 University of Guelph, Environmental Sciences This research is aimed at detecting Fe-oxide pedofeatures distributed in Humic Gleysols, Luvic Gleysols and Gleysols, specific considering Orthic, Fera, Eluvial, Rego, Humic subgroups. Representative sections of Gleysols from across Canada were obtained from the Canadian Soil Thin Section Collection, archived in the Soil Imaging Laboratory at the University of Guelph. A high resolution digital camera was utilized to capture RGB imagery from each thin section under oblique incident light, plane polarized light and cross polarized light. Object-based image segmentation software (eCognition) is used to delineate pedofeatures and voids in the digital imagery. Specific attention is given to the nature and distribution of Fe oxides in relation to soil voids. 234 1 Greenhouse and Processing Crops Research Centre, AAFC Agricultural and Environmental Policy Analysis, AAFC 2 The recent agro-environmental indicator study showed that national averages of residual soil nitrogen (RSN) (annual N input minus N output) increased from 9.4 kg N ha-1 in 1981 to 23.6 kg N ha-1 in 2011, driving by the continuous increases in fertilizer N usage and biological N fixation. This, in consequence, caused 35% of RSN loss annually in British Columbia, 45-65% in Central Canada and 75-90% in Atlantic Canada through leaching and it varied with soil and climate condition. The objective of this paper was to (1) to introduce the CANB v4.0 model and I/O structure, (2) to map and display the model’s outputs at different regional scales, and (3) to carry out scenario analysis using a CANB v4-scenario model. There were 6 to 11 agricultural regions in each province of Canada for policy and economic analysis and these regions were integrated with the CANBv4-scenario model to test how the RSN and N leaching loss change in response to policy scenarios in the Agricultural region and other Ecoreigonal scales. Four preliminary scenarios were tested and each has 4 levels: (1) reducing fertilizer N by 10, 20, 30 and 40%; (2) reducing manure N by 10, 20, 30 and 40%, (3) reducing N fixation by decreasing alfalfa land area by 10, 20, 30 and 40% while increasing improved pasture the same land area, respectively and (4) combining scenarios 1, 2 and 3. The results showed that RSN and N lost decreased linearly with the reduction of fertilizer N, manure N, and N fixation, respectively. By combined scenario 4, N leaching loss was reduced by up to 40% under a 20% reduction in three N sources simultaneously under 2011 land use practice. The differences of the RSN were clearly shown in Canadian Agricultural Regions. More policy scenarios will be tested by the CANBv4-scenario model in the future. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Modeling of Soil Water and Salt Dynamics with Shallow Water Table and Its Effects on Root Water Uptake and Heihe Arid Wetland, Gansu, China Ying Zhao, Huijie Li, Bing Si University of Saskatchewan, Soil Science In the Heihe River basin, China, increased salinity and water shortages represent serious threats to the sustainability of arid wetlands. It is critical to understand the interactions between soil water and salts and their effects on plant growth. In this study, the Hydrus-1D model was used in an arid wetland located in the Middle Heihe River to investigate the effects of soil water, salt, groundwater table and groundwater salinity on Chinese tamarisk root water uptake. On the basis of model calibration and validation with observed data, scenario analyses were performed under different water tables, groundwater salinities and irrigation quantities. The results showed that (i) Chinese tamarisk root distribution was greatly affected by soil water and salt distribution in soil profile, and about 73.8% of the roots were distributed in 20-60 cm; (ii) root water uptake accounted for 89.8% of the potential maximal value when water stress was considered, it only accounted for 49.8% of that when both water and salt stress were considered. Root water uptake was very sensitive to the fluctuations of water table, and was greatly reduced when the water table is either excessively deep or shallow; and (iii) arid wetland vegetation exhibited a high level of groundwater dependence even though shallow groundwater resulted in increased soil salinization, and irrigation applied prior to the growing season can effectively increase root water uptake by leaching salts from the root zone. We concluded that suitable water table, groundwater salinity coupled with proper irrigation are key factors for sustainable development of arid wetlands. 235 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S14: General Soil Science 236 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Corn yield and quality as a function of nitrogen fertilization and soil texture Athyna Cambouris1, Khaled Alotaibi1, Noura Ziadi1, Nicolas Tremblay2 1 Soil and Crops Research and Development Centre, AAFC Horticultural Research and Development Centre, AAFC 2 Optimal N fertilization in corn production system needs to consider soil texture as an important factor that can influence crop production and N fertilizer efficiency. The objective of this study was to evaluate the effect of soil surface textural groups and N fertilizer rates on grain yield, N uptake, N uptake efficiency (NUE), thousand kernel weight (TKE) and test weight. A study was carried out at 12 site-years in Quebec, with the experimental treatments of N rate (0-250 kg N ha-1) and four soil textural groups (clayey, loamy, sandy belonging to the Podzolic soil order and sandy belonging to the Gleysolic soil order). Fertilization and its interaction with soil textural groups showed a significant effect on all measured parameters whereas textural group had only a significant effect on grain yield and N uptake. When averaged across the N fertilizer rates, the greatest yield and N uptake were obtained in loamy soil. Per unit of N applied, N fertilization was more effective in loamy soil, providing higher yield, N uptake, NUE, TKE and test weight. This study suggests that soil surface texture should be taken into consideration to achieve an optimal N fertilization. 237 Predicting ammonia volatilization from swine slurry application using DNDC: Model development Katelyn Congreves, Brian Grant, Baishali Dutta, Ward Smith, Martin Chantigny, Philippe Rochette, Raymond Desjardins Agriculture and Agri-Food Canada Process-based biogeochemical models are needed for providing N loss predictions, but most lack a direct or accurate estimation of NH3 volatilization. This paper presents the improvement of the Canadian version of the Denitrification-Decomposition model (DNDC v.CAN) by integrating a sub-model capable of predicting NH3 volatilization after the field application of slurry. The validation dataset included NH3 flux measurements collected for 4-7 d after 16 applications of swine slurry (May 1999 to Sept 2005) to the surface of grassland and bare soil in Québec (n=114). Our model developments improved the ability of DNDC to predict NH3 loss and provided reasonable estimates for cumulative NH3 volatilization (i.e., average relative error of 5.7%). Consequently, more accurate estimates of soil mineral N were derived from the developed DNDC v.CAN model compared to the previous version of DNDC. Based on a sensitivity analysis using DNDC v.CAN, the model was capable of demonstrating the significant influence of slurry pH and NH4+ adsorption on NH3 volatilization. The improved prediction of NH3 volatilization using DNDC v.CAN enhances the ability to accurately model N cycling and predict overall N loss from agro-ecosystems. To further improve NH3 volatilization predictions, we recommend DNDC developments focus on modelling soil unsaturated flow, slurry infiltration rates, and soil pH buffering. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Supervision of Nutrition, From Soil to Kitchen Excess more than deficiency of boron affects the physiological features in highbush blueberry Mohammad Ali Daei1, Manizheh Daei2 Cristian Meriño-Gergichevich1*, M. ReyesDíaz1,2 1 Medical Doctor and Researcher in Biology 2 Masters Student in Soil Science While soil science, agronomy, animal husbandry, and human nutrition have all the same goal, “human nourishment” surprisingly, this unique goal is tracked by separate groups at different sections without common understanding and cooperation. Although, plants are autotrophic and animals, including human are heterotrophic creatures, the principle of absorption, metabolism, excretion, and genetics essentially are the same. At least in the domain of nutrition, there are much experience and data; which can be share to avoid recurrent mistakes and energy waste. Agriculturists have a unique opportunity to do several experiments on plant nutrition without any concern of critics, what in the field of medicine is impossible. So results of such experiences may help doctors a lot. For example, thanks to vast investigation in soil science and agronomy, you are clearly aware of the unique role of minerals, in gen regulation and expression. . For instance, boron deficiency in plants, block the pollen tub formation and prevent fruit set and boron excess causes a radical change in flower buds and transformed them to vegetative bud. These changes are impossible without suppressing some and activating other groups of gens. As you see minor manipulation in minerals may have huge consequences. There are similar experiences in animal husbandry too. Veterinarians fear from mineral manipulation in animal food. Fluctuations of minerals act through hormones to activate or inactivate some gens. This is a common process in multi cellular creatures. But unfortunately in the field of medicine the risks of mineral toxicity and imbalance are not fully understood as yet. Using tremendous amount of mineral fortified foods and drinks which are their recommendation is well expressive of their thinking. They stress on deficiencies inappropriately. Human brain is more susceptible to minerals. Iodine deficiency can restrict the brain development severely (cretinism).On the other hand, lithium can control one of the most severe Psychiatric disorders (Mania). Lead toxicity and its side effect on brain and behavior is another example. In presentation we will focus on two important points. A / The most vita and critical nutrients in human foods are minerals. B / Nutrition is a unique concept with a unique target. So education of nutrition needs modifications in order to all students of bio sciences can feel this unity. 238 1 Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Technological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera 2 Departamento de Ciencias Químicas y Recursos Naturales, Universidad de La Frontera Boron (B) is an essential micronutrient required for growth and development in higher plants due to its role in a great variety of biochemical and physiological processes. However, its requirement and role in oxidative stress remains poorly studied in highbush blueberry (Vaccinium corymbosum L.). This species is widely cultivated in Chilean Andisols (pH≤5.5) and its leaves and fruits are rich in antioxidants. The aim was to know the effect of deficient and excessive B supply on chemical and physiological features in highbush blueberry. One year old plants of Brigitta and Legacy cultivars, grown in a peat moss: vermiculite (1:1) mixture at pH 4.5 for 30 days under greenhouse conditions, were treated with increased B (0, 50, 200, 400 y 800µM applied as H3BO3). The study considered the following determinations: leaf and root B concentrations, mean relative growth rate (MRGR), oxygen radical absorbance capacity (ORAC) and oxidative stress (TBARS). Leaf and root B (mg kg -1) was significantly increased (~80%) in Brigitta at 400 and 800 µM, and 200 and 400 µM respectively, in comparison to the treatment with 0 µM. For Legacy, B concentration was raised from 200 µM (P≤0.05), whereas in roots did not showed any changes. Excessive B caused a reduction (~30%) of MRGR (mg FW day-1) compared to 0 µM B in both cultivars (P≤0.05). In leaves and roots of both cultivars, higher ORAC was observed under deficiency than excessive B (P≤0.05). A reduction of TBARS was observed when 50 and 200 µM B were added to Legacy and Brigitta plants, respectively (P≤0.05). In conclusion, highbush blueberry seems to be more sensitive to an excess than to a deficiency of B. This could be an important factor to improve physiological and antioxidant performance in highbush blueberry subjected to a potential stress in acid soil conditions. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effect of Tillage, Cover Crop and CornSoybean Rotation on Soil Pore Space Indices Evolution of soil hydraulic properties during repeated cycles of drainage and recharge Dinesh Panday, Nsalambi Nkongolo Yann Périard1, Silvio José Gumiere1, Alain Rousseau2, Jean Caron1 Lincoln University, Agriculture and Environmental Sciences 1 Knowledge of the impact of soil management practices on soil properties is important in farm management. We studied the effect of tillage (no-till vs conventional tillage), cover crop (no-rye vs rye) and crop rotation (continuous corn, continuous soybean, corn-soybean and soybean-corn) treatments on soil pore space indices: the relative gas diffusion coefficient (Ds/Do) and the pore tortuosity factor (τ). The study was conducted on a silt loam soil planted to corn and soybean at Freeman farm of Lincoln University in 2011-2014 growing seasons. The experimental design was a randomized complete block with 16 treatments and 3 replications. Soil samples were collected at two depths: 0-10 and 10-20 cm, and their fresh weights recorded. Samples were later oven dried at 105°C for 72 h. After drying, air-filled porosity (AFP) and total pore space (TPS) were calculated and later used in Marshall, Buckingham, Sallam, Millington and Jin-Jury models for predicting Ds/Do and τ. Results showed significant interactions between tillage and cover crop in all four years for Ds/Do (p < 0.05). In addition, similar interactions were also observed for τ (p < 0.05). Ds/Do and τ can be used to assess the impact of soil management practices on soil physical properties. 239 Laval University, Soils and Agri-Food Engineering Institut national de la recherche scientifique: Centre Eau, Terre et Environnement 2 The installation of drainage systems may cause anthropic-induced evolution of soil properties. In fact, hydroconsolidation (drainage and recharge cycles and flooding), filtration and clogging soil pores by colloidal particle accelerated by water management (irrigation and drainage) will reduce drainage capacity by alteration of soil hydraulics properties. Tomodensitometric analysis allows the study a number of hydrodynamic processes of soils especially for the transport of colloidal particles and consolidation. The main objective of this work is to characterize temporal evolution of hydraulic properties of a sandy soil during repeated drainage and recharge cycles using a medical CT-scan. A soil columns laboratory experiment was setup in 2013 and 2014, pressure head, input and output water flow, tracer monitoring (KBr and ZrO2) and tomographic analyses have been used to predict soil hydraulic properties. The results showed that the drainage and recharge accelerated cycles alter soil hydraulic properties causing a reduction of the soil drainage capacity. Knowledge about the mechanisms responsible for this anthropic-induced soil evolution is capital for water management in intense agricultural systems, such as cranberry farms. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Strategies to improve the phosphorus uptake efficiency of Al-tolerant wheat cultivars grown in volcanic soils The relationship between compaction and structural properties of Québec soils Yan Xu1, Noura Ziadi2, Léon-Étienne Parent1 Alex Seguel, A. Morales, P. Campos, A. Bizarro, P. Cornejo, F. Borie, Universidad de la Frontera, Scientific and Technological Bioresource The economy of the Southern Region of Chile is mainly supported on traditional agriculture developed practically under volcanic soils being wheat the main crop. Volcanic acid soils, mainly Andisols, have serious fertility limitations such as high levels of exchangeable Aluminum (Al-phytotoxicity) and high P fixation capacity (P deficiency). In developing countries, as Chile, which have limited access to P fertilizer, there is a need to develop plants that are Al tolerant and more P efficient. The aim of this study was to analyze, as selection parameters, adaptive mechanisms developed by wheat genotypes, such as root architecture, P desorption by organic acid (OA) and the association with mycorrhizal fungi. Two wheat cultivars Al-tolerant and P-efficient (‘T1’ and ‘T2’) and one Alsensitive and P-inefficient (‘S1’) were selected and a couple of experiments were carried out both in pots and mineral solution under two Al concentrations (35 and 0.14 % Al-sat) and three P levels (0, 100 and 200 ppm). Based in root architecture the results showed that ‘T1’ and ‘T2’ presented longer root hairs than ‘S1’. Higher citrate and malate root exudation were observed at high Al levels in ‘T1 and ‘T2’ in comparison with ‘S1’and it was decreased over time. Furthermore, citric, malic and oxalic acids appear to desorbs the highest amounts of P in these soils. Mycorrhizal propagules were increased at high Al levels and low P, especially in ‘T1’ and ‘T2’. Therefore, higher organic acid exudation in P-deficiency treatments and Al-tolerant cultivars is related with a high P solubilization, P efficient cultivars have a better capacity for soil exploring by longer root hair and the presence of AM fungi populations adapted to these conditions is raising the adaptation of some wheat cultivars growing in acidic soils. Based in the strategies analyzed, we suggest the use of “T1” and “T2” in Chilean volcanic soils with high Al-levels and low P available. We fully acknowledge the financial support of the FONDECYT 3140623 grant (A. Seguel) and FONDECYT 1130541 grant (F. Borie) from Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) Chile. 240 1 Université Laval Soils and Crops Research and Development Centre, AAFC 2 Soil compaction is one of the major problems reducing crop yield, increasing N and P requirements, and affecting hydraulic properties. Quantitative evaluation of soil compaction is essential to develop management strategies that minimize the harmful effect of intensive agriculture and improve soil structure. Soil aggregate is an important characteristic for soil structure that could affect soil resistance to compaction. Organic matter influences soil structural stability and soil compaction. The objective of this study is to determine the relationship between soil structural properties and compaction. Surface and sub-surface soil samples from 30 sites where texture varied from sandy loam to clay were analyzed for organic carbon, bulk density, aggregate size distribution, and compaction using a modified Proctor Test for maximum bulk density. Degree of compaction characterizing the state of soil compactness was calculated by rationing bulk density and maximum density. Distribution of soil aggregates was expressed as the log-ratio balances between macro-(>2 mm and 0.25-2 mm) and micro-aggregates (<0.25 mm) and between larger (>2 mm) and smaller (0.25-2 mm) macro-aggregates, to avoid methodological biases when analyzing compositional data. Data were statistically analyzed using regressions and correlations. Maximum bulk density was inversely proportional to optimum moisture content (R2=0.80). Correlation analyses revealed that the balance between macro-(>2 mm and 0.25-2 mm) and micro-aggregates (<0.25 mm) was related positively to organic carbon content and negatively to bulk density. The results showed that organic matter played an important role in reducing compaction effects. Low maximum bulk density and low degree of compaction related to higher organic carbon content. Moreover, soils with higher organic carbon content or lower balance contrasting larger (>2 mm) and smaller (0.25-2 mm) macro-aggregates would reach maximum density values at higher moisture levels. Soil aggregates showed no correlation with maximum bulk density and the degree of compaction across soil textural classes and management practices. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S15: Biochar in Agriculture and Environment/ Le Biochar en Agriculture et en Environnement 241 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Effet de l’ajout de biochar sur la symbiose tripartite Ensifer meliloti-Rhizophagus irregularis-Luzerne (Medicago sativa L.) Reconstructed topsoil using biochar or oxidized lignite for site reclamation Asfaw Bekele, Julie Roy, Michelle Young Héla Selmi1, Vicky Levesque1, Richard Hogue2 Hani Antoun1 1 Université Laval, Département des sols et génie agroalimentaire & CRIV 2 Institut de recherche et de développement en agroenvironnement L’effet bénéfique de la fixation de N2 par la symbiose tripartite Rhizobium-légumineuses-endomycorhizes est bien connu. De plus, l’utilisation du biochar comme amendement favorise la croissance des plantes en améliorant les propriétés physicochimiques ou l’activité biologique du sol. Le but de ce travail est de déterminer l’effet d’un biochar commercial (700°C, copeaux de pin), sur la symbiose tripartite: Medicago sativa L. cv Calypso- Ensifer meliloti- Rhizophagus irregularis. L’expérience a été réalisée selon un dispositif en blocs complets aléatoires dans des pots de 1 L contenant un sol de jachère (loam pH 7, 4,35% matière organique) amendé ou pas en biochar (15 ou 30%, v:v). Chaque pot reçoit 800 spores de R. irregularis DAOM 197198 et 10 graines de luzerne inoculées avec log 3 ufc/graine, de la souche A2 ou S14 de E. meliloti. Après 16 semaines de croissance, la luzerne a été récoltée pour déterminer les masses (fraîche et sèche) de la partie aérienne, l’indice de nodulation et le % de colonisation des racines avec les mycorhizes. L’inoculation de la luzerne avec les souches A2 ou S14 n’a pas eu d’effet significatif sur les rendements de la luzerne, indiquant la présence dans le sol de souches efficaces d’E. meliloti. Par contre A2 et S14 ont augmenté significativement le taux de colonisation des racines par les mycorhizes, de 81% par rapport au témoin non inoculé. En présence de 15% de biochar, cette augmentation a été de 171 %. Néanmoins, avec 30% de biochar la masse sèche de la partie aérienne a diminué de 13% (p < 0,05) par rapport au témoin sans biochar, malgré l’augmentation de l’indice nodulaire. D’autres essais seront requis afin de vérifier si les stimulations observées par l’ajout de biochar à 15% se traduisent par une augmentation des rendements au champ. 242 Imperial Oil Resources Stripping of topsoil is a necessary part of most mining and oil and gas extraction activities. While salvaging of topsoil has recently become an integral part of these activities, topsoil shortage has hindered the successful reclamation of older well sites. We have been conducting research since 2001 on the utility of biochar or oxidized lignite (humalite) co-applied with labile organic matter (LOM; alfalfa, wheat straw and sawdust) to subsoil to reconstruct functioning and sustainable agronomic topsoil for use in site reclamation. The research consisted of bench scale study (2001-2005), field, and greenhouse studies (2003-2014). Biochar or humalite applied together with LOM to subsoil enhanced soil organic carbon retention and resulted in topsoil as productive as native topsoil. While our data showed that functioning topsoil can be reconstructed from either biochar or humalite applied together with LOM to subsoil, biochar was not cost effective for a large scale field application. The use of humalite coapplied with LOM is being tested at two central Alberta well sites undergoing reclamation. Preliminary results show performance (as measured by aboveground biomass production) of reconstructed topsoil relative to off lease control topsoil to be site dependent, with soil moisture and nutrient availability differences at the two sites as potential limiting factors. However, the observed difference in aboveground biomass between the reconstructed topsoil and natural topsoil at these sites is expected to narrow in the next few years as the added LOM decomposes and N immobilization and mineralization equilibrium is established. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Comparing Black Carbon Measurements from Thermal Analysis and National-Scale MIR Calibrations in Minesoils Chan1, Peltre2, Effects of biochars soil application on nitrogen and phosphorus availabilities Mohammed Benbrahim1, Laurent Kremer1, Jessica Haas1, Catherine Heinrich1-2, Myriam Drolet1-3*, Nicolas Thevenin1, Matthieu Hauptmann1 Plante3, Jaclyn Clément Alain Thomas Baumgartl1, Peter Erskine1 1 University of Queensland, Mined Land Rehabilitation University of Copenhagen, Plant and Environmental Science 3 University of Pennsylvania, Earth and Environmental Sciences 2 Coal minesoils are highly disturbed and degraded Anthroposols with the likely presence of black carbon (BC) and coal contributing to their total carbon levels. Poor soils contribute to the problems of erosion, slope stability and plant establishment. The ability to assess the effectiveness of rehabilitation at rebuilding the biologically available carbon levels to improve soil health is desirable. Multivariate curve resolution (MCR) is used to create components from evolved CO2 thermographs produced from the thermal analysis of minesoils. The MCR analysis is applied to minesoils grouped by similarity. The component curves reflect carbon containing matter with different thermal degradation signatures. These curves are used as proxies for more labile or biologically active carbon and recalcitrant carbon forms, BC, coal and inorganic carbon based on their peak CO2 evolution temperatures. The MCR results are compared to MIR/PLSR predictions for carbon estimates attained from applying the Australian Soil Carbon Research Programme (SCaRP) calibrations. Also, the suitability of using the SCaRP calibration based on natural and agricultural soils on minesoils is discussed. 243 1 RITTMO AgroEnvironnement DUT Génie Biologique (U.H.A.) 3 Cégep de Lévis-Lauzon 2 Biochar, a solid product generated by anaerobic biomass pyrolysis, presents both environmental (carbon storage in soils) and agronomic interests (improvement of the physical, biological and chemical soil properties). The present studies were conducted in the framework of the European European BioenNWBiochar project. The objectives of these studies were to determine the effects of different biochars on the nitrogen and phosphorus availabilities in agricultural soils. Several laboratory tests and greenhouse assays were conducted in France. The studies were realised with 4 biochars of diverse biomass origins (digestate, litter, wood). The Biochars were obtained at pilot scale in Nederland. The biochars were added to soil at equivalent level of 4 T DM per hectare. Phosphorus bioavailability assay consists in the comparison of biochars potential fertilization efficiency by growing Ray-grass on a limited amount of soil with standardized intake of phosphorus. After ray grass growth, biomass was determined. Also, water soluble phosphorus was determined in the soil-biochars melange. For nitrogen, two tests were realised. The nitrogen volatilization was determined after urea and biochar addition to soil. The soil was incubated in incubation chambers for 15 days. Ambient air without ammonium is injected into the incubation chamber. Ammonium is then volatilized trapped in a sulfur acid solution. The leaching test was conducted in lysimeter study covered with a Ray-grass crop. The percolate water was collected to determine their nitrate content. Biochars seem to increase the phosphorus availability but aims to increase the ammonia volatilisation if urea is used as fertilizer. The different results obtained to determine the effects of intake of biochar on the availability of nitrogen and phosphorus and assess the value of biochar in agriculture. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Evaluating the effect of biochar application on some biological quality and properties of vermicompost Faiza Hossaini, Hossein Ali Alikhani, Ahmad Ali Pourbabaee, Leila Mohammadi University of Tehran During pyrolysis process, microporosity of organic matter increases and these micropores provide such places for microorganisms as a microhabitat. It is expected that biochar application in vermicompost will increase the quality and biological properties of vermicomposts due to the increase in microbial population, moisture retention and micronutrient leaching prevention. For this purpose, biochars were prepared from three substrates of wheat stalk, rice husk and compost of municipal wastes in two pyrolysis temperature of 200°C for 4 hours and 500°C for 6 hours and they were added 20 gr/ Kg of vermibeds. After incubation period, biological properties such as microbial carbon and basal microbial respiration were measured and compared with control treatments which had no biochar. To evaluate vermicompost quality, germination test was carried out by two methods of direct seed method and water extract method on lentil seeds. Results indicated that prepared biochar from rice husk in 200°C had increased microbial biomass compared to the control and municipal compost biochar in 200°C had the most effect on increasing released CO2 while rice husk biochar in 200°C had the least effect and decreased released CO2 from vermibed surfaces. Direct seed method test also showed that rice husk biochar in 200°C increased seedling significantly. Seed germination was greater in the water extract method; however the control vermicompost extract increased germination of seeds compared to the extracts of vermicompost containing biochar. Regarding high amount of microbial carbon in the treatment containing rice husk biochar in 200°C, decrease in microbial respiration is probably due to chemical absorption of carbon by biochar surfaces. Thus, using biochar in vermibed could increase biological quality and properties of resulting vermicompost because of microbial population increase and carbon source increase. 244 Amendments to increase maize (Zea maize) yield in an alfisol in Sri Lanka Srimathie Indraratne1, J.A. Surani Chathurika1, Warshi Dandeniya1, Darshani Kumaragamage2 1 University of Peradeniya, Agriculture University of Winnipeg, Environmental Studies and Sciences 2 Alfisols are the predominant soil types in the dry zone of Sri Lanka where high-input agriculture is practiced due to low soil fertility. This study evaluated beneficial management practices to achive high production in maize (Zea maize). The experiment was conducted in the Low Country Dry Zone (DL1b) with Typic Rhodustalf. A site-specific fertilizer (SF) recommendation was formulated using the modified missing element technique. Four treatments, (1) SF, (2) biochar applied at 0.5% by weight with SF (BC+SF), (3) rock powder applied at 5% with SF (RP+SF) and (4) un-amended control (C) were initially tested at the greenhouse for 72 days and later in field for a complete growing season of maize. Soil was neutral, non-saline, sandy clay loam in texture with a moderate cation exchange capacity (16.0 cmol+/kg) and low organic matter content (1.5%). According to initial analysis soil was deficient in available N, P, S, Ca, Zn, and Cu, and sufficient in Mg and Fe. In the greenhouse, plant dry weight increased significantly with the addition of amendments i.e., fertilizers alone (SF), or with biochar (BC+SF) or with rock powder (RP+SF). In the field, plant dry weights and length of cob significantly increased in all treatments compared with the control, but no significant differences were observed between amendment treatments and the SF only treatment. Significantly higher grain yield was observed for the BC+SF (4990 kg/ha) and RP+SF (5260 kg/ha) treatments than other treatments. Complete nutrient package developed based on soil analysis significantly increased the plant growth. High C:N ratio amendment (biochar) did not limit the available nutrients in the greenhouse or in the field. The results of the field experiment suggest that biochar and rock powder with adequate nutrients effectively improved soil constraints in the Alfisol and significantly increased the maize yield. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Biochar Alters Activity of Extracellular Enzyme and Abundance of Bacterial and Fungal Populations in Subtropical Mangroves Ling Luo, Ji-Dong Gu University of Hong Kong, Biological Sciences Biochar has attracted more and more attention due to its essential role in adsorbing pollutants, improving soil fertility, and modifying greenhouse gas emission. However, the influences of biochar on extracellular enzyme activity and microbial abundance are still lack and debatable. Currently, there is no information about the impact of biochar on mangrove ecosystems. Therefore, we explored the effects of biochar on extracellular enzyme activity and microbial abundance in subtropical mangrove sediment, and further estimated the contribution of biochar to C sequestration. In this study, sediments were amended with 0 (control), 0.5, 1.0 and 2.0% of biochar and incubated at 25oC for 90 days. After incubation, enzyme activities (including phenol oxidase (PHO), peroxidase (POD), β-glucosidase (GLU), N-acetylglucosaminidase (NAG) and acid phosphatase (ACP)), microbial abundance (both bacteria and fungi), and the increased percentage of C content were determined. Both increase (PHO and GLU) and decrease (POD, NAG and ACP) of enzyme activities were observed in biochar treatments, but only POD activity showed significant differences (at least p < 0.01) compared to the control. Moreover, the activities of all enzymes were significantly related to biochar addition rate (at least p < 0.05). On the other hand, bacterial and fungal abundance in biochar treatments were remarkably lower than control (p < 0.001), and the significantly negative relationship (p < 0.05) between bacterial abundance and biochar addition rate was found. Furthermore, the increased percentage of C seems to gradually increase with biochar addition rate, which provides direct evidence for applying biochar to mitigate climate change. Given the importance of microorganisms and enzyme activities in sediment organic matter decomposition, the increased C sequestration might be explained by the decrease of microbial abundance and POD activity after biochar intervention. 245 Biochar reduces loss of organic amendments in tropical field conditions Thi Phuong Ngo1,2, Cornelia Rumpel3, Pascal Jouquet4,5 1 Bioren centre, universidad de la Frontera Laboratoire de Sol et Environnement, Université de Lorraine 3 CNRS, iEES Paris, campus AgroParisTech, ThivervalGrignon 4 IRD, IEES Paris, centre IRD Ile de France, Bondy, France 5 Indian Institute of Science 2 In Vietnam, the utilization of exogenous organic amendments such as manure, its compost and vermicompost (EOMs) and biochar made from bamboo residues are suggested as novel approaches for improving soil fertility, plant growth as well as sequestering carbon. In this study, decomposition of EOMs as well as their mixture with biochar in terrestrial ecosystems under tropical conditions was evaluated using the litterbags method. The objectives of this study are (1) to estimate the carbon and nitrogen loss of manure, its compost and vermicompost as well as biochar during one year field exposure and (2) to evaluate the effect of biochar on this loss under the tropical conditions. Different substrates alone and their mixture (EOM:Biochar 1:1) was placed into individual nylon litterbags and exposed on the surface of soil under the natural condition during one year in Hanoi. Four bags of each treatment were collected after 0, 4, 16, 52 weeks of incubation for elemental analysis. Our results showed an important loss of carbon and nitrogen of organic EOMs as well as biochar under rainfall conditions. After one year of incubation, only about 30% carbon and 40% nitrogen of EOMs remained. A loss of more than 40% of C and 60 % of N was recorded for biochar at the end of the experiment, probably by the loss of small particulates and dissolved compounds by leaching. Interestingly, the mixtures of biochar with other EOMS were significantly more resistance to organic matter loss than substrates alone. Protection of biochar by EOM was probably due to physical protection. We therefore suggest that the mixture of EOM with biochar may be beneficial for increasing C sequestration due to mutual protection of EOM as well as biochar. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 S17: Soils of Natural, Managed and Intensive Forest Systems/ Les Sols de Systems Forestiers Naturels, Aménagés et Intensifs 246 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Mechanical site preparation treatment influences soil microbial community structure and function: Identification of multifunctional molecular stress indicators of sylvicultural practices Caractérisation des chemins (écoulements) préférentiels superficiels sur l’efficacité du piégeage des sediments d’une bande riveraine à l’aide de l’imagerie LIDAR et de la modélisation Jean-Philippe Buffet, Claude Guertin, Philippe Constant Nody Civil, Silvio José Gumiere INRS- Institut Armand-Frappier Mechanical site preparation (MSP) for treatment of soil and vegetation alleviates low seedling survival by increasing soil temperature, water retention and nutrients availability. Scarification and mounding are commonly used for forest restoration. Although soil disturbances resulting of these sylvicultural practices depend on treatment intensity, very few attempts were made to investigate the impact of MSP on soil microbial communities. A 4-year old experimental larch plantation was examined to verify the impact of MSP on soil biogeochemical structure. Soil samples were collected from replicated plots comprising simple trenching, double trenching, mounding, and inverted site preparation. Native forest patches conserved within the experimental plantation were also sampled as reference. Analysis of soil nutrients, bacterial biomass and gaseous exchanges unveiled no statistically significant difference among the plots. However, intensification of MSP resulted to higher variations in trace gas exchanges than trenching and native forest. A combination of the biological and physicochemical parameters was used to define a multifunctional-based classification of the soil samples. According to this classification, soil samples collected from simple trenching were those showing more similarity to samples collected in native forests. Highthroughput sequencing of bacterial 16S rRNA gene showed the absence relationship between MSP method and microbial community structure. Soil pH and C:N stoechiometry were the most important variables to explain the distribution of ribotypes in soil. Nevertheless, indicator ribotypes were identified for each of the four multifunctional soil classes previously defined. One of these ribotypes affiliated to Myxococcales (Deltaproteobacteria) was proposed as stress indicator of sylvicultural practices because it was found in soil samples collected in the MSP plots for which the multifunctional index diverged most from the index observed in native forest. Because the four MSP methods led to undistinguishable growth performance of larch seedlings in the plantation, we recommend simple trenching for the establishment of intensive larch monocultures. 247 Université Laval, Département des sols et de genie agroalimentaire Les bandes riveraines sont considérées comme une des meilleures pratiques agricoles pour diminuer l’érosion et la contamination de l’eau de surface. Celles-ci ont la capacité de filtrer l’eau de ruissellement contribuant ainsi à réduire la pollution diffuse des eaux de surface. De plus, elles permettent de diminuer les vitesses d’écoulement des eaux de ruissellement qui lorsqu’elles sont élevées peuvent provoquer la formation de rigoles. Au Québec, l’évaluation de l’efficacité des bandes riveraines tient compte uniquement des caractéristiques physiques de la bande. L’objectif principal de ce travail est d’évaluer l’influence des principales composantes sur la performance des bandes riveraines. L’utilisation de la technologie LIDAR (light detection and ranging: détection et télémétrie par la lumière) terrestre permettra de caractériser les trajectoires des eaux de ruissellement en milieu agricole jusqu’à la bande riveraine et de produire des informations précises sur son évolution et son efficacité à retenir les sédiments. Par la suite, des modélisations numériques seront conduites afin de reproduire les conditions d’écoulements superficiels, le piégeage des sédiments et l’évolution de la bande riveraine dans le temps. Le modèle validé servira à titre prévisionnel pour quantifier les principaux phénomènes effectifs dans une bande riveraine et son efficacité. Celui-ci permettra aussi de guider la conception de ces structures ou de proposer des mesures correctives, selon la réalité du champ, pour optimiser le fonctionnement des bandes riveraines dans le milieu agricole. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Soil temperature changes can be a reliable indicator of global climate change under hot and desert ecosystems Baseline Assessment of Soil Chemical Properties and Nutrients in Ituri Forest, Democratic Republic of Congo Abdurashid Elmi Nsalambi Nkongolo1,2, Jean-Jaques Mbuyi Kakuni2, Michel Lokonda2, Floribert Budjo3, Jean-Remy Makana3, Corneille Ewango3 Department of Environment and Tech Management Deserts ecosystems are most sensitive to small changes in environmental conditions to the extent that land use pressure has become so serious that dry land agriculture and natural habitats may be threatened in the long term. The primary objectives of this study were to: 1) quantify changes in temperature in the soil profile at different locations under different management practices in the state of Kuwait, and 2) examine whether or not soil temperature fluctuations follow a similar trend to air temperature fluctuations. The findings from this study represent original contribution to our understanding as it sheds some light on whether or not soil temperature changes can be used as a reliable indicator of global climate change. 248 1 Lincoln University, Agriculture and Environmental Sciences Institut Facultaire des Sciences Agronomiques (IFA), Science du Sol et Eau 3 Centre de Formation et de Recherche en Conservation Forestière 2 The sustainable use of the soil resource requires extensive knowledge about its genesis, morphology, and properties. Consequently, soil data are basis for improved land use management and soil conservation. Unfortunately, while urgently needed, up-to-date data on tropical soils is not always available. We conducted a baseline assessment of soil chemical properties (pH, CEC, percent base saturation, OM, TC, TN), major (N, P, K, S, Mg, Ca and S) and minor (Al, Fe, Mn, Cu, Na, Zn) nutrients in Lenda1-Forest Dynamic Plot (FDP), Ituri Forest, Democratic Republic of Congo. Eighty soil samples were collected at 10 cm depth from soil surface in the middle of each 20 m x 20 m sub-plot inside the 10 ha FDP. The coordinates of each sampling location were recorded using global positioning system. Soil samples were air-dried, saved in plastic bag and brought to the United States of America for chemical analysis. Results showed that the soil had an average pH of 4.03 and a CEC of 5.76. Among the major nutrients, Ca (209.23 mg/kg) was more abundant, but occupied only 16% of CEC which was dominated by H (63%). As expected, Al (677.54 mg/kg) and Fe (284.79 mg/kg) were the major micronutrients in this soil. Soil nutrients responded to a range of variogram models, but dominated by the Gaussian model. The range of spatial variability (A0) varied from 313 to 910 m, indicating a strong autocorrelation at larger distances. Coefficients of determination (R2) ranged from 0.42 to 0.92 suggesting a highly developed structure, especially for Al (R2= 0.91), Mg (R2= 0.92), Ca (R2= 0.92) and pH (R2= 0.90). These results suggest an inconsistent spatial pattern of soil nutrients at Lenda1-FDP. More studies are therefore needed in deeper horizons for a better understanding of the spatial variability of soil nutrients in this pristine forest. Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Carbon losses from deforestation in Russia during 1990-2012 Alexander Trunov, Institute of Global Climate and Ecology In Russia deforestation is associated with the transfer of forest land to settlements during infrastructure construction. The statistical data on the construction of pipelines, railways, roads, transmission lines, oil and gas wells, etc. by regions were collected. Deforestation area was estimated by multiplication of these data by the percentage of forest land. The assumption was made on the complete oxidation of C pools in biomass, dead wood and litter in the year of deforestation. For soils 2 options considered: total destruction of soil cover under the solid pavements and partial disturbance if areas remained grass cover. For the first option the complete oxidation of SOM at one year was assumed. For the second one we estimated the partial reduction in the soil C stocks during 20 years after conversion. The area of deforestation in Russia for the period from 1990 to 2012 was 28.7 th. ha per year and within 2000 – 2012 it declined to 23.1 th. ha/yr. Average annual losses of C in biomass, litter and dead organic matter pools in general for forested lands were 1,360.5; 239.3 and 273.8 th. tons, respectively. The area with the complete destruction of the soil cover corresponded to about 19% of the total area of deforestation. Average losses of soil organic C in these lands estimated around 743.6 th. tons per year within the period 19902012. For partial destruction of soils the C losses comprised in average 182.0 th. tons per year. Thus, the total deforestation C losses in Russia for the period 1990-2012 corresponded to 64,384.5 th. tons or about 2,800 th. tons annually. 249 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Corresponding Authors Authors are displayed by session order 250 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Keynote Speakers Duxbury, John Cornell University New York, USA jmd17@cornell.edu Hayhoe, Doug Tyndale University College Ontario, Canada dhayhoe@tyndale.ca Kraemer, Stephan University of Vienna Vienna, Austria stephan.kraemer@univie.ac.at Humphreys, Elyn Carleton University Ontario, Canada elyn.humphreys@carleton.ca Hale, Beverley University of Guelph, Environmental Sciences Ontario, Canada bhale@uoguelph.ca Viscarra Rossel, Raphael Commonwealth Scientific and Industrial Research Organization (CSIRO) Canberra, Australia raphael.viscarra-rossel@csiro.au Smalla, Kornelia Julius Kühn-Institute, Epidemiology and Pathogen Diagnostics Braunschweig, Germany kornelia.smalla@jki.bund.de Pachepsky, Yakov Beltsville, Agricultural Research Center Maryland, USA yakov.pachepky@ars.usda.gov Wagai, Rota National Institute of Agro-Environmental Science Kannondai, Japan rota@affrc.go.jp Spokas, Kurt United States Department of Agriculture (USDA) – Agricultural Research Service Minnesota, USA kurt.spokas@ars.usda.gov Leinweber, Peter University of Rostock, Soil Science Rostock, Germany peter.leinweber@agrarfak.uni-rostock.de Quideau, Sylvie University of Alberta, Department of Renewable Resources Alberta, Canada sylvie.quideau@ualberta.ca Rochette, Philippe Agriculture and Agri-Food Canada Québec, Canada philippe.rochette@agr.gc.ca Celi, Luisella University of Torino, Soil Biochemistry Torino, Italy luisella.celi@unito.it 251 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Oral Sessions Session 1 Chantigny, Martin Soil & Crops Research and Development Centre, AAFC Québec, Canada martin.chantigny@agr.gc.ca Monreal, Carlos Agriculture and Agri-Food Canada Québec, Canada carlos.monreal@agr.gc.ca Frossard, Emmanual Institute of Agricultural Sciences, Group of Plant Nutrition Zurich, Switzerland emmanuel.frossard@usys.ethz.ch Roy, Amal Brandon Research Centre, AAFC Manitoba, Canada amal.roy@agr.gc.ca Schoenau, Jeff University of Saskatchewan, Soil Science Saskatchewan, Canada jeff.schoenau@usask.ca Jayarathne, Kumundu University of Winnipeg, Environmental Studies and Sciences Manitoba, Canada dilshikajayarathne@gmail.com Vaillancourt, Mathieu Université Laval Québec, Canada jd.mathieu.vaillancourt@gmail.com Jilling, Andrea University of New Hampshire, Natural Resources and the Environment New Hampshire, USA aj5@wildcats.unh.edu Weiseth, Blake University of Saskatchewan Saskatchewan, Canada blake.weiseth@usask.ca Jouogo Noumsi, Christelle Université de Sherbrooke, Chemistry & Biology Québec, Canada christelle.jouogo.noumsi@usherbrooke.ca Zhang, Tiequan Agriculture and Agri-Food Canada Québec, Canada tiequan.zhang@agr.gc.ca Li, Haixiao Université de Bordeaux, Science and Environment Bordeaux, France lihaixiao001@gmail.com Maltais-Landry, Gabriel Stanford University, Biology California, USA gmaltais@stanford.edu 252 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 2 Benjannet, Rim Université Laval Québec, Canada rim.benjannet.1@ulaval.ca Nwaichi, Eucharia University of Massachusetts Amherst Massachusetts, USA nodullm@yahoo.com Cennerazzo, Johanne Université de Lorraine, Environnements Continentaux Nancy, France johanne.cennerazzo@gmail.com Olobatoke, Rosaline North-West University, CARST Mafikeng, South Africa yemisirose205@yahoo.com Colinet, Gilles Université de Liège, Gembloux Agri-Bio-Tech Wallonia, Belgium gilles.colinet@ulg.ac.be Shu, Weixi Dalhousie University, Agriculture Nova Scotia, Canada wx205944@dal.ca Gillis, J. Daniel McGill University, Bioresource Engineering Québec, Canada joseph.gillis@mail.mcgill.ca Vasiluk, Luba University of Guelph, Environmental Sciences Ontario, Canada lvasiluk@uoguelph.ca McShane, Heather McGill University Québec, Canada heather.mcshane@mail.mcgill.ca Zaghloul, Alaa National Research Center Dokki, Cairo, Egypt alaazaghloul2002@yahoo.com Miller, Jim Agriculture & Agri-Food Canada Québec, Canada jim.miller@agr.gc.ca Zhang, Yu Dalhousie University Nova Scotia, Canada charlotte91zy@gmail.com Nadler, Simon Université du Québec à Montréal Québec, Canada nadlersimon@hotmail.com 253 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 3 Arcand, Melissa Saskatoon Research Centre, AAFC Saskatchewan, Canada mmarcand@gmail.com Kandeler, Ellen University of Hohenheim, Soil Science and Land Evaluation Stuttgart, Germany kandeler@uni-hohenheim.de Baraniya, Divyashri University of Florence, Agriculture and Environmental Sciences Florence, Italy dbaraniya@unifi.it Preusser, Sebastian University of Hohenheim, Soil Science and Land Evaluation Stuttgart, Germany s.preusser@uni-hohenheim.de Bazghaleh, Navid University of Saskatchewan, Semiarid Prairie Agricultural Research Centre Saskatchewan, Canada navid.bazghaleh@usask.ca Sukdeo, Nicole University of Northern British Columbia, Natural Resources and Environmental Studies British Columbia, Canada nicole.sukdeo@unbc.ca Carson, Michael Laurentian University Ontario, Canada mcarson@laurentian.ca VandenBygaart, Bert Eastern Cereal and Oilseed Research Centre, AAFC Ontario, Canada bert.vandenbygaart@agr.gc.ca Inubushi, Kazuyuki Chiba University, Horticulture Chiba, Japan inubushi@faculty.chiba-u.jp Session 4 Diochon, Amanda Lakehead University, Geology Ontario, Canada adiochon@lakeheadu.ca Oufqir, Sofia University of Minnesota, Soil, Water and Climate Minnesota, USA oufqirsofia@gmail.com Huang, Qiayun Huazhong Agricultural University, Agricultural Microbiology Wuhan, South China qyhunag@mail.hzau.edu.cn Schmidt, Michael Cornell University, Soil and Crop Sciences New York, USA ms2958@cornell.edu Staunton, Siobhan Institut National de la Researche Agronomique (INRA) - UMR Eco & Sols Montpellier, France staunton@montpellier.inra.fr Martinez, Carmen Enid Cornell University, Soil and Crop Sciences New York, USA cem20@cornell.edu 254 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 5 Abdi, Dalel Soils and Crops Research and Development Centre, AAFC Québec, Canada dalel.abdi.1@ulaval.ca Hepp, Catherine University of Copenhagen, Plant and Environmental Sciences Copenhagen, Denmark hepp@plen.ku.dk Aubin, Melanie Université du Québec à Chicoutimi, Départment des sciences fondamentales Québec, Canada melanie.aubin@uqac.ca Khosravi, Kambiz Dalhousie University, Engineering Nova Scotia, Canada k.khosravi@dal.ca Pimentel, Rejane University of Guelph Ontario, Canada rejane@uoguelph.ca Bosch, Anna University of Tuebingen, Geosciences Tuebingen, Germany anna.bosch@geographie.uni-tuebingen.de Simpson, Andre University of Toronto Ontario, Canada andre.simpson@utoronto.ca Chelabi, Hakima AgroEnviroLab Québec, Canada hchelabi@agro-enviro-lab.com Vasiluk, Luba University of Guelph, Environmental Sciences Ontario, Canada lvasiluk@uoguelph.ca Gillespie, Adam University of Saskatchewan, Canadian Light Source Inc. Saskatchewan, Canada adam.gillespie@lightsource.ca Gowda, Ankapura Haranahalli Ramaswamy Institute of Higher Education Karnataka, India ankapuratgowda@rediffmail.com Session 6 Adelekun, Mayowa University of Manitoba, Soil Science Manitoba, Canada adelekmf@myumanitoba.ca Drury, Craig Agriculture and Agri-Food Canada Ontario, Canada craig.drury@agr.gc.ca Amadi, Chukwudi University of Saskatchewan, Soil Science Saskatchewan, Canada cca423@mail.usask.ca Fentabil, Mesfin University of British Columbia, Earth & Environmental Sciences British Columbia, Canada selames@gmail.com Baah-Acheamfour, Mark University of Alberta, Renewable Resources Alberta, Canada mbaahach@ualberta.ca Sulaimain, Muhammed University of Guelph, Environmental Sciences Ontario, Canada mbinsula@uoguelph.ca Dhillon, Gurbir Singh University of Saskatchewan Saskatchewan, Canada gud510@mail.usask.ca Thompson, Karen University of Guelph, Environmental Sciences Ontario, Canada kthomp08@uoguelph.ca 255 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 7 Cade-Menun, Barbara Semiarid Prairie Agriculture Research Centre, AAFC Saskatchewan, Canada barbara.cade-menun@agr.gc.ca Missong, Anna Institute of Bio- and Geosciences (IBG-3), Agrosphere Research Centre Jülich, Germany a.missong@fz-juelich.de Fraser, Tandra Colorado State University, Environmental Sustainability Colorado, USA tandra.fraser@colostate.edu Munira, Sirajum University of Manitoba, Soil Science Manitoba, Canada muniras@myumanitoba.ca Giles, Courtney James Hutton Institute Dundee, United Kingdom courtney.giles@hutton.ac.uk Schneider, Kim University of Guelph, Environmental Sciences Ontario, Canada kschne01@uoguelph.ca Gottselig, Nina Institute of Bio- and Geosciences, Agrosphere Research Centre Jülich, Germany n.gottselig@fz-juelich.de Wagner-Riddle, Claudia University of Guelph, Environmental Sciences Ontario, Canada cwagnerr@uoguelph.ca Westphal, Megan University of Manitoba, Soil Science Manitoba, Canada westphme@cc.umanitoba.ca Haygarth, Philip Lancaster University, Lancaster Environment Centre Lancashire, United Kingdom p.haygarth@lancaster.ac.uk Jiang, Xiaoqian Institute of Bio- and Geosciences (IBG-3) Jülich, Germany x.jiang@fz-juelich.de Session 8 Fontaine, Laurent Université Laval Québec, Canada laurent.fontaine.1@ulaval.ca Jeanne, Thomas Institut de recherche et de développement en agroenvironnement (IRDA) Québec, Canada thomas.jeanne@irda.qc.ca Goyer, Claudia Potato Research Centre, AAFC New Brunswick, Canada claudia.goyer@agr.gc.ca Navarro Borrell, Adriana Semiarid Prairie Agricultural Research Centre, AAFC Saskatchewan, Canada adriana.navarroborrell@agr.gc.ca Helgason, Bobbi Saskatoon Research Centre, AAFC Saskatchewan, Canada bobbi.helgason@agr.gc.ca Scandellari, Francesca Free University of Bolzano Bolzano, Italy francesca.scandellari@unibz.it 256 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 9 Andronak, Lindsey Western Ag Innovations Inc. Saskatchewan, Canada lindseyandronak@westernag.ca Masse, Jacynthe University of British Columbia British Columbia, Canada jacynthe.masse@alumni.ubc.ca Hazlett, Paul Natural Resources Canada, Canadian Forest Service Canada phazlett@nrcan.gc.ca Van Rees, Ken University of Saskatchewan Saskatchewan, Canada ken.vanrees@usask.ca Kroetsch, David Science and Technology Branch, AAFC Ontario, Canada david.kroetsch@agr.gc.ca Vasseur, Claire Biodôme de Montréal Québec, Canada cvasseur@ville.montreal.qc.ca MacIntyre, Jane Tyndale University College Ontario, Canada jmacintyre@tyndale.ca Session 11 Brown, Robin University of Saskatchewan Saskatchewan, Canada robin.brown@usask.ca andrew.pinsonneault@mail.mcgill.ca Viaud, Valérie Institut national de la recherche agronomique, UMR Rennes, France valerie.viaud@rennes.inra.fr Cowan, Elizabeth Carleton University Ontario, Canada elizabethcowan3@cmail.carleton.ca Wang, Xiaoyue University of Saskatchewan, Soil Science Saskatchewan, Canada xiaoyue.wang@usask.ca Pinsonneault, Andrew McGill University, Soil Science Québec, Canada 257 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 12 Adamchuk, Viacheslav McGill University, Bioresource Engineering Québec, Canada viacheslav.adamchuk@mcgill.ca Leiva-Baron, Fabio Rodrigo National University of Columbia Bogotá, Columbia frleivab@unal.edu.co Biswas, Asim McGill University, Natural Resource Sciences Québec, Canada asim.biswas@mcgill.ca Mbodj, Awa Université Laval Québec, Canada awa.mbodj.1@ulaval.ca Furze, Shane University of New Brunswick New Brunswick, Canada furze.shane@gmail.com Moulin, Alan Brandon Research Centre, AAFC Manitoba, Canada alan.moulin@agr.gc.ca Heung, Brandon Simon Fraser University, Geography British Columbia, Canada bha4@sfu.ca Zhang, Jin Simon Fraser University, Geography British Columbia, Canada jza18@sfu.ca Session 13 Biswas, Asim McGill University, Natural Resource Sciences Québec, Canada asim.biswas@mcgill.ca Nkongolo, Nsalambi Lincoln University, Agriculture and Environmental Sciences Missouri, USA nkongolo@lincolnu.edu Burton, David Dalhousie University Nova Scotia, Canada dburton@dal.ca Price, Gordon Dalhousie University, Nova Scotia, Canada gprice@dal.ca Mome Filho, Edison Aparecido University of São Paulo, Agriculture São Paulo, Brazil edison_mome@hotmail.com Zebarth, Bernie Potato Research Centre, AAFC New Brunswick, Canada bernie.zebarth@agr.gc.ca 258 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 14 Botula, Yves-Dady University of Kinshasa, Natural Resource Management Kinshasa, Democratic Republic of Congo ydbotula@yahoo.fr Lafond, Jean Agriculture and Agri-Food Canada Québec, Canada jean.lafond@agr.gc.ca Cambouris, Athyna Soil Crops Research and Development Centre (SCRDC), AAFC Québec, Canada athyna.cambouris@agr.gc.ca Larney, Francis Agriculture and Agri-Food Canada Québec, Canada francis.larney@agr.gc.ca Lupwayi, Newton Lethbridge Research Centre, AAFC Alberta, Canada newton.lupwayi@agr.gc.ca Chai, Lilong Lethbridge Research Centre, AAFC Alberta, Canada lilong.chai@agr.gc.ca Reid, Keith Agriculture and Agri-Food Canada Ontario, Canada keith.reid@agr.gc.ca Cheng, Yi State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science Beijing, China ycheng@issas.ac.ca Roy, Amal Brandon Research Centre, AAFC Manitoba, Canada amal.roy@agr.gc.ca Dutta, Baishali Agriculture and Agri-Food Canada Ontario, Canada baishali.dutta85@gmail.com Voegel, Tanja University of British Columbia, Biology British Columbia, Canada tanja.voegel@ubc.ca Dyck, Miles University of Alberta, Renewable Resources Alberta, Canada mdyck@ualberta.ca Yang, Xueming Greenhouse and Processing Crops Research Centre, AAFC Ontario, Canada xueming.yang@agr.gc.ca Halde, Caroline Université Laval Québec, Canada caroline.halde.1@ulaval.ca Keiblinger, Katharina University of Natural Resources and Life Sciences, Soil Research Vienna, Austria katharina.keiblinger@boku.ac.at 259 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 15 Brassard, Patrick McGill University, Bioresource Engineering Québec, Canada patrick.brassard@irda.qc.ca Pace, Benjamin University of New South Wales, Materials Science and Engineering Sydney, Australia b.pace@unsw.edu.au Karppinen, Erin University of Saskatchewan Saskatchewan, Canada erin.karppinen@usask.ca Rees, Frédéric Université de Lorraine – INRA Soils and Environment Nancy, France frederic.rees@univ-lorraine.fr Lange, Sébastien Université Laval, Centre de Recherche sur les Matériaux Renouvelables (CRMR) Québec, Canada suzanne.allaire@fsaa.ulaval.ca Stewart, Kayla Laurentian University, Biology Ontario, Canada km_stewart@laurentian.ca Levesque, Vicky Université Laval, Soils and Agri-Food Engineering & Horticultural Research Center Québec, Canada vicky.levesque.1@ulaval.ca Vidana Gamage, Duminda McGill University, Natural Resource Sciences Québec, Canada Duminda.vidanagamage@mail.mcgill.ca Mitchell, Perry University of Toronto, Chemistry Ontario, Canada perry.mitchell@mail.utoronto.ca Lou, Kangyi University of Alberta Alberta, Canada sxchang@ualberta.ca Naisse, Christophe Université Paris VI, Ecology and Environmental Sciences Paris, France christophe.naisse@univ-lorraine.fr Session 16 Aspinall, Doug Ontario Ministry of Agriculture, Food and Rural Affairs Ontario, Canada doug.aspinall@ontario.ca Pelletier, Vincent Université Laval Québec, Canada vincent.pelletier.8@ulaval.ca Bruulsema, Tom International Plant Nutrition Institute Ontario, Canada tom.bruulsema@ipni.net Tremblay, Nicolas Agriculture and Agri-Food Canada Québec, Canada nicolas.tremblay@agr.gc.ca Bulot, Diane Université Laval, Pavillon de l’Envirotron Québec, Canada diane.bulot.1@ulaval.ca Yang, Xueming Greenhouse & Processing Crops Research Centre, AAFC Ontario, Canada xueming.yang@agr.gc.ca Caron, Jean Université Laval, Sols et de Génie Alimentaire Québec, Canada jean.caron@fsaa.ulaval.ca 260 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 17 Barnes, William University of Alberta, Renewable Resources Alberta, Canada wbarnes@ualberta.ca Pennock, Dan University of Saskatchewan, Soil Science Saskatchewan, Canada dan.pennock@usask.ca Brais, Suzanne Université du Québec en Abitibi-Témiscamingue (UQAT) Québec, Canada suzanne.brais@uqat.ca Perreault, Lili Université du Québec en Abitibi-Témiscamingue (UQAT) Québec, Canada lili.perreault@uqat.ca Collin, Alexandre Université du Québec à Montréal (UQAM) Québec, Canada alxcollin@gmail.com Poirier, Vincent Université Laval, Center for Forest Research Québec, Canada vincent.poirier.1@ulaval.ca Fortier, Julien Université du Québec à Montréal (UQAM) – Forest Research of the Eastern Townships Québec, Canada fortier.julien@courrier.uqam.ca Reid, Anya University of British Columbia British Columbia, Canada anyamartinareid@gmail.com Shabaga, Jason University of Toronto Mississauga Ontario, Canada jason.shabaga@utoronto.ca Fugère, Martine Université de Sherbrooke Québec, Canada martine.fugere@usherbrooke.ca Smenderovac, Emily University of Toronto, Forestry Ontario, Canada esmenderovac@laurentian.ca Gorgolewski, Adam University of Toronto Ontario, Canada adam.gorgolewski@mail.utoronto.ca Strukelj, Manuella Université du Québec en Abitibi-Témiscamingue (UQAT) Québec, Canada manuella.strukelj-humphery@uqat.ca Hazlett, Paul Natural Resources Canada, Canadian Forest Service Ontario, Canada phazlett@nrcan.gc.ca Keys, Kevin Nova Scotia Department of Natural Resources Nova Scotia, Canada kevin.keys@novascotia.ca 261 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Poster Presentations Session 1 Audette, Yuki University of Guelph Ontario, Canada yaudette@uoguelph.ca Mora, Maria de la Luz Universidad de la Frontera Temuco, Chile mariluz.mora@ufrontera.cl Barbieux, Sophie University of Liège, Gemblous Agri-Bio Tech Wallonia, Belgium sophie.barbieux@ulg.ac.be N’Dayegamiye, Adrien Research and Development Institute for the AgroEnvironment (IRDA) Quèbec, Canada adrien.ndaye@irda.qc.ca Bilošová, Hana Agroresearch Rapotín Ltd. Rapotín, Czech Republic h.karabcova@centrum.cz Nechi, Chaima Laval University Québec, Canada chaima.nechi.1@ulaval.ca Celi, Luisella University of Torino, Soil Biochemistry Torino, Italy luisella.celi@unito.it Nkongolo, Nsalambi Lincoln University of Missouri, Agriculture and Environmental Sciences Missouri, USA nkongolo@lincolnu.edu Halloran, Samantha Trent University, Environmental & Life Sciences Dept. Ontario, Canada samanthahalloran@trentu.ca Nowell, Peter University of Guelph, Environmental Sciences Ontario, Canada pnowell@uoguelph.ca Kar, Gourango University of Saskatchewan Saskatchewan, Canada gok203@mail.usask.ca Nyiraneza, Judith Agriculture and Agri-Food Canada Prince Edward Island, Canada judith.nyiraneza@agr.gc.ca Kiani, Mina University of Alberta, Science Alberta, Canada mkiani@ualberta.ca Parades, Cecilia Universidad de la Frontera Temuco, Chile cecilia.paredes@ufrontera.cl Leon Castro, Leonardo McGill University, Natural Resource Sciences Québec, Canada leonardo.leoncastro@mail.mcgill.ca Parra, Leyla Universidad de la Frontera, Center of Plant, Soil Interaction and Natural Resources Biotechnology Temuco, Chile leyla.p.alumna@gmail.com Lu, Caiyan State Key Laboratory of Forest and Soil Ecology, Pollution Ecology and Environmental Engineering, Chinese Academy of Sciences Shenyang, China microyan76@126.com Pei, Chengyin Trent University, Environmental Life and Sciences Ontario, Canada chengyinpei@trentu.ca MacCormick, Elizabeth Dalhousie University, Agriculture Nova Scotia, Canada ea.maccormick@gmail.com Poblete, Patricia Universidad de la Frontera Temuco, Chile patty.grant87@gmail.com Monreal, Carlos Agriculture and Agri-Food Canada Québec, Canada carlos.monreal@agr.gc.ca 262 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Pourhassan, Nina Université de Sherbrooke, Centre Sève, Chimie Quèbec, Canada nina.pourhassan@usherbrooke.ca St. Luce, Mervin Soils and Crops Research and Development Centre, AAFC Québec, Canada mervin.st.luce@agr.gc.ca Price, Gordon Dalhousie University, Engineering Nova Scotia, Canada gprice@dal.ca Thomas, Ben McGill University, Natural Resource Sciences Québec, Canada ben.thomas@mail.mcgill.ca Redel, Yonathan Universidad de la Frontera, Scientific and Technological Bioresource Nucleus Temuco, Chile yonathan.redel@ufrontera.cl Tikasz, Peter McGill University Québec, Canada peter.tikasz@mail.mcgill.ca Royer, Isabelle Agriculture and Agri-Food Canada Quèbec, Canada isabelle.royer@agr.gc.ca Whittaker, Jennifer Crops and Livestock Research Centre, AAFC Prince Edward Island, Canada jwhittaker@dal.ca Shi, Yi University of Chinese Academy of Sciences, Forest and Soil Ecology Shenyang, China shiyi@iae.ac.cn Session 2 Aoki, Shinsuke Meiji University, Agriculture Tokyo, Japan s_aoki@meiji.ac.jp Grobelak, Anna Czestochowa University of Technology, Environmental Engineering Czestochowa, Poland agrobelak@is.pcz.czest.pl Bower, Jennifer University of Vermont, Geology Vermont, USA jbower@uvm.edu Kacprzak, Malgorzara Czestochowa University of Technology, Environmental Engineering Czestochowa, Poland mkacprzak@is.pcz.czest.pl Bien, January Czestochowa University of Technology, Institute of Environmental Engineering Czestochowa, Poland enecz@is.pcz.czest.pl Lafrance, Pierre Université INRS – Centre Eau, Terre et Environnement (ETE) Québec, Canada pierre.lafrance@ete.inrs.ca Dai, Nancy University of Guelph Ontario, Canada ndai@uoguelph.ca Laird, Amanda University of Guelph Ontario, Canada laird@uoguelph.ca Gonzalez Linares, Monica McGill University, Natural Resource Sciences Québec, Canada monica.gonzalezlinares@mail.mcgill.ca Martin, Maria Università di Torino, DISAFA Turin, Italy maria.martin@unito.it 263 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Murata, Alison University of Alberta, Renewable Resources Alberta, Canada amurata@ualberta.ca Thorn, Ryan University of Guelph Ontario, Canada thornr@uoguelph.ca Neczaj, Ewa Czestochowa University of Technology, Institute of Environmental Engineering Czestochowa, Poland enecz@is.pcz.czest.pl Vialykh, Elena University of Calgary, Chemistry Alberta, Canada elena.vialykh@ucalgary.ca Staunton, Siobhan INRA, UMR Eco & Sols Montpellier, France staunton@montpellier.inra.fr Session 3 Abdellatif, Lobna Agriculture and Agri-Food Canada Saskatchewan, Canada lobna.abdellatif@agr.gc.ca Fraser, Tandra Colorado State University, Environmental Sustainability Colorado, USA tandra.fraser@colostate.edu Alotaibi, Fahad Université de Montréal, Soil Science Québec, Canada fahad.alotaibi@umontreal.ca García Berumen, José Abraham Centro de Investigación y de Estudios Avanzados (IPN)-Departamento de Biotecnología y Bioquímica Mexico City, Mexico jagarcia@ira.cinvestav.mx Aulakh, Gurpreet Laurentian University, Biology Ontario, Canada gs_aulakh@laurentian.ca Gebala, Aurelia University of Hohenheim, Soil Science and Land Evaluation Stuttgart, Germany aurelia.gebala@uni-hohenheim.de Bandekar, Basanti Dalhousie University Nova Scotia, Canada basanti.bandekar@gmail.com Gillis, Daniel McGill University, Bioresource Engineering Québec, Canada joseph.gillis@mail.mcgill.ca Carneiro, Marco Aurelio Carbone Universidade Federal de Lavras Minas Gerais, Brazil marcocarbone@dcs.ufla.br Grishkan, Isabella University of Haifa, Evolution Haifa, Israel grishkan@research.haifa.ac.il Constant, Philippe INRS – Institut Armand-Frappier Québec, Canada philippe.constant@iaf.inrs.ca Guo, Galen Laurentian University Ontario, Canada gguo@laurentian.ca Durán, Paola Universidad de la Frontera, Scientific and Technological Bioresource Nucleous Temuco, Chile paola.duran@ufrontera.cl Huangfu, Yanchong University of Tennessee, Biosystems Engineering & Soil Science Tennessee, USA yhuangfu@vols.utk.edu 264 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Huot, Hermine University of New York, Earth and Environmental Sciences New York, USA hermine.huot@yahoo.fr Najat, Nassr RITTMO Agroenvironnement Alsace, France najat.nassr@rittmo.com Jazestani, Jamshid McGill University, Bioresource Engineering Québec, Canada jamshid.jasestani@mail.mcgill.ca Noyce, Genevieve University of Toronto, Physical and Environmental Sciences Ontario, Canada genevieve.noyce@mail.utoronto.ca Kotzé, Elmarie University of the Free State, Soil, Crop and Climate Sciences Bloemfontein, Free State, South Africa kotzee@ufs.ac.za Ouertani, Selmene Université Laval, Centre de recherche et d’innovation des végétaux Québec, Canada selmene.ouertani.1@ulaval.ca Liu, Ting Nanjing Agricultural University/ McGill University China/ Canada ting.liu3@mail.mcgill.ca Pichette, Jennifer Laurentian University Ontario, Canada jx_pichette@laurentian.ca Mafa-Attoye, Tolulope University of Guelph, Environmental Science Ontario, Canada tmafaat@uoguelph.ca Silamikele, Baiba University of Latvia, Microbiology and Biotechnology Riga, Latvia silamikelebaiba@gmail.com Merino, Carolina Universidad de la Frontera, Ciencias Quimicas y Recursos Naturales Temuco, Chile c.merinoguzman@gmail.com Smenderovac, Emily Laurentian University, Living with Lakes Center Ontario, Canada esmenderovac@laurentian.ca Williams-Johnson, Shanay Laurentian University, Living with Lakes Center, Biology Ontario, Canada swilliamsjohnson@laurentian.ca Monokrousos, Nikolaos Department of Biological Applications and Technology, University of Ioannina Ioannina, Greece nmonokro@bio.auth.gr Session 4 Abail, Zhor McGill University, Natural Resource Sciences Québec, Canada zhor.abail@mail.mcgill.ca Chalavi, Vida Sari Agricultural Sciences and Natural Resources University Sari, Mazandaran, Iran v.chalavi@sanru.ac.ir Aoyama, Masakazu Hirosaki University, Agriculture and Life Science Aomori, Japan aoyamam@hirosaki-u.ac.jp Contreras, Francisco University de la Frontera Temuco, Chile franciscocontrerasrivas@gmail.com Calabi-Floody, Marcela Universidad de la Frontera, Soil Interaction and Natural Resources Biotechnology Temuco, Chile marcela.calabi@gmail.com Coward, Elizabeth University of Pennsylvania Pennsylvania, USA ecoward@sas.upenn.edu 265 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Engoke, Canon International Institute of Tropical Agriculture (IITA) Ibadan, Oyo State, Nigeria c.engoke@cgiar.org Siebers, Nina Institute of Bio- and Geosciences, IBG-3 Agrosphere Jülich, Germany n.siebers@fz-juelich.de Kazumichi, Fujii Forestry and Forest Products Research Institute, AFFRC Ibaraki, Japan fkazumichi@affrc.go.jp Staunton, Siobhan INRA, UMR Eco&Sols Montpellier, France staunton@montpellier.inra.fr Taghizadeh-Toosi, Arezoo Aarhus University Aarhus, Denmark arezoo.taghizadeh-toosi@agro.au.dk Ishida, Débora Ayumi Universidade de São Paulo Piracicaba, Brazil deboraishida@usp.br Vieira Batista, Marcos Antonio Instituto Federal de Educação Ciência e Tecnologia do Ceará-IFCE Fortaleza, Brazil batistamar@ig.com.br Lin, Lisa University of Toronto Ontario, Canada lisa.lin@mail.utoronto.ca Xu, Jianming Institute of Soil and Water Resources and Environmental Science, Zhejiang University Zhejiang, China jmxu@zju.edu.cn Lun, Olivia University of Toronto Ontario, Canada olivia.lun@mail.utoronto.ca Merino, Carolina Universidad de la Frontera, Ciencias Quimicas y Recursos Naturales Temuco, Chile c.merinoguzman@gmail.com Xu, Renkou State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science Beijing, China rkxu@issas.ac.cn Pronk, Geertje University of Waterloo, Earth and Environmental Sciences Ontario, Canada gpronk@uwaterloo.ca Zavarzina, Anna Moscow State University, Soil Science Moscow, Russia zavarzina@mail.ru Session 5 Abdi, Dalel Soil and Crops Research and Development Centre, AAFC Québec, Canada dalel.abdi.1@ulaval.ca Estrada-Medina, Hector Universidad Autónoma de Yucatán (UADY) Yucatán, Mexico hestr001@gmail.com Gan, Qianjun McGill University, Food Science Québec, Canada qianjun.gan@mail.mcgill.ca Audette, Yuki University of Guelph Ontario, Canada yaudette@uoguelph.ca Gauthier, Mélanie Agro-Enviro-Lab Québec, Canada mgauthier@agro-enviro-lab.com Cade-Menun, Barbara Semiarid Prairie Agriculture Research Centre, AAFC Saskatchewan, Canada barbara.cade-menun@agr.gc.ca 266 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Gillespie, Adam University of Saskatchewan, Canadian Light Source Inc. Saskatchewan, Canada adam.gillespie@lightsource.ca Sidhu, Savitoz McGill University, Natural Resource Sciences Québec, Canada savitoz.sidhu@mail.mcgill.ca Makhani, Mitalie McGill University, Natural Resource Sciences Québec, Canada mitalie.makhani@mail.mcgill.ca Simpson, Myrna University of Toronto, Environmental NMR Centre, Environmental and Physical Sciences Ontario, Canada myrna.simpson@utoronto.ca Périard, Yann Laval University, Soils and Agri-Food Engineering Québec, Canada yann.periard-larrivee.1@ulaval.ca Taki, Rezvan University of Guelph, Environmental Sciences Ontario, Canada rtaki@uoguelph.ca Plante, Alain University of Pennsylvania Pennsylvania, USA aplante@sas.upenn.edu Yang, Xueming Greenhouse and Processing Crops Research Centre, AAFC Ontario, Canada xueming.yang@agr.gc.ca Porter, Timothy University of Nevada Las Vegas Nevada, USA tim.porter@unlv.edu Session 6 Adamchuk, Viacheslav McGill University, Bioresource Engineering Québec, Canada viacheslav.adamchuk@mcgill.ca Lindsay, Brin Potato Research Centre, AAFC New Brunswick, Canada lindsay.brin@gmail.com Ahmed, Naeem McGill University Québec, Canada naeemahm@live.com Cambareri, Sebastian University of Guelph, Environmental Sciences Ontario, Canada scambare@uoguelph.ca Alotaibi, Khaled Soils and Crops Research and Development Centre, AAFC Québec, Canada kalotaib@gmail.com Charles, Anaïs McGill University, Natural Resource Sciences Québec, Canada ac.anais.charles@gmail.com Amadi, Chukwudi University of Saskatchewan, Soil Science Saskatchewan, Canada cca423@mail.usask.ca Congreves, Katelyn Agriculture and Agri-Food Canada Québec, Canada kcongrev@uoguelph.ca Amiro, Brian University of Manitoba Manitoba, Canada brian_amiro@umanitoba.ca Hans, Geetkamal University of British Columbia Okanagan, Biochemistry British Columbia, Canada geet.hans@ubc.ca 267 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Jennewein, Stephen University of Florida, Everglades Research and Education Centre Florida, USA skiesareours@ufl.edu Raeini-Sarjaz, Mahmoud Sari Agricultural Sciences and Natural Resources University Sari, Mazandaran, Iran m.raeini@sanru.ac.ir Leite Luiz, F. C. Piauí Federal University Piauí, Brazil luiz.f.leite@embrapa.br Singh, Jessica University of Guelph, Environmental Sciences Ontario, Canada jsingh16@uoguelph.ca Menasseri-Aubry, Safya INRA, UMR INRA/Agrocampus Ouest « Sol Agro et hydrosystème Spatialisation » Rennes, France safya.menasseri@agrocampus-ouest.fr Vandenbygaart, Bert Eastern Cereal and Oilseed Research Centre, AAFC Ontario, Canada bert.vandenbugaart@agr.gc.ca Palacios, Joahnn IRDA (Research and development institute for the Agri-environment) Québec, Canada joahnn.palacios@irda.qc.ca Wu, Lan-Fang Chinese Academy of Sciences, Geographical Sciences and Natural Resources Research Beijing, China wulf@igsnrr.ac.cn Panday, Dinesh Lincoln University, Center of Excellence GIS Lab, Agriculture and Environmental Sciences Missouri, USA dinesh.panday239@my.lincolnu.edu Session 7 Abdi, Dalel Soils and Crops Research and Development Centre, AAFC Québec, Canada dalel.abdi.1@ulaval.ca Moore, Tim McGill University, Geography Québec, Canada tim.moore@mcgill.ca Wang, Yu Chinese Academy of Sciences, Soil Science Bejing, China wangyu@issas.ac.cn Cade-Menun, Barbara Semiarid Prairie Agriculture Research Centre, AAFC Saskatchewan, Canada barbara.cade-menun@agr.gc.ca Ziadi, Noura Agriculture or Agri-Food Canada Québec, Canada noura.ziadi@agr.gc.ca Damar, Hada Université Laval, Soils and Agri-Food Engineering Québec, Canada dhdammam@yahoo.fr Giles, Courtney James Hutton Institute Dundee, United Kingdom courtney.giles@hutton.ac.uk 268 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 8 Acuna, Jacquelinne Universidad de la Frontera, Scientific and Biotechnological Bioresource Nucleus (BIORENUFRO) Temuco, Chile jacquelinne.acuna@ufrontera.cl Masse, Jacynthe University of British Columbia British Columbia, Canada jacynthe.masse@alumni.ubc.ca Munroe, Jake University of Guelph, Environmental Sciences Ontario, Canada jake.munroe89@gmail.com Arcand, Melissa Agriculture and Agri-Food Canada Québec, Canada mmarcand@gmail.com Navarro Borrell, Adriana Semiarid Prairie Agricultural Research Centre, AAFC Saskatchewan, Canada adriana.navarroborrell@agr.gc.ca Arteaga, Jessica Laurentian University, Biology Ontario, Canada jarteaga@laurentian.ca Chen, Chen South China Institute of Environmental Sciences Guangzhou, China chen.chen6@mail.mcgill.ca Neufeld, Katarina University of British Columbia, Land and Food Systems British Columbia, Canada neufeld.katarina@gmail.com Helgason, Bobbi Saskatoon Research Centre, AAFC Saskatchewan, Canada bobbi.helgason@agr.gc.ca Spence, Jennifer Dalhousie University Nova Scotia, Canada jennifer.spence@dal.ca Jeanne, Thomas Insititut de recherche et de développement en agroenvironnement (IRDA) Québec, Canada thomas.jeanne@irda.qc.ca Ziadi, Noura Agriculture or Agri-Food Canada Québec, Canada noura.ziadi@agr.gc.ca Session 9 Burton, David Dalhousie University Nova Scotia, Canada dburton@dal.ca Jingyi, Yang Greenhouse and Processing Crops Research Centre, AAFC Ontario, Canada jingyi.yang@agr.gc.ca Krzic, Maja University of British Columbia, Land and Food Systems British Columbia, Canada krzic@interchange.ubc.ca Yates, Thomas University of Saskatchewan, Soil Science Saskatchewan, Canada tom.yates@usask.ca 269 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 11 Hobson, Claire Carleton University, Environmental Sciences Ontario, Canada cmhobson@connect.carleton.ca Shahariar, Md Shayeb University of Saskatchewan, Soil Science Saskatchewan, Canada shayeb.shahariar@usask.ca Lafond, Jonathan Université Laval, départment des sols et de genie agroalimentaire Québec, Canada jonathan.lafond.2@ulaval.ca Silamikele, Inese University of Latvia, Biology Riga, Latvia Inese.silamikele@lu.lv Zhang, Zhidan University of Saskatchewan, Soil Science Saskatchewan, Canada zhidanzhang79@163.com Saint-Laurent, Diane Université du Québec à Trois-Rivières (UQTR) Québec, Canada diane.saint-laurent@uqtr.ca Session 12 Samson, Marie-Élise Laval University, Agricultural and Food Sciences Québec, Canada marie-elise.samson.1@ulaval.ca Zhang, Yakun McGill University, Natural Resource Sciences Québec, Canada yakun.zhang@mail.mcgill.ca Zhang, Jin Simon Fraser University, Geography British Columbia, Canada jza18@sfu.ca Session 13 Andronak, Lindsey Western Ag Innovations Saskatchewan, Canada lindseyandronak@westernag.ca Congreves, Katelyn Agriculture and Agri-Food Canada Québec, Canada kcongrev@uoguelph.ca Banihashemi, Avid University of Waterloo, Ecohydrology Research Group Ontario, Canada a2baniha@uwaterloo.ca Elliot, Jane Environment Canada Ontario, Canada jane.elliot@ec.gc.ca Cambouris, Athyna Soil and Crops Research and Development Centre, AAFC Québec, Canada athyna.cambouris@agr.gc.ca Grewer, David University of Toronto at Scarborough Ontario, Canada david.grewer@mail.utoronto.ca Gumiere, Silvio Université Laval, départment des sols et de génie agroalimentaire Québec, Canada silvio-jose.gumiere@fsaa.ulaval.ca Cao, Yu University of Guelph, Environmental Sciences Ontario, Canada ycao02@uoguelph.ca 270 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 He, Wentian Greenhouse and Processing Crops Research Centre, AAFC Ontario, Canada wentian.he@agr.gc.ca Sidhu, Savitoz McGill University, Natural Resource Sciences Québec, Canada savitoz.sidhu@mail.mcgill.ca Tian, Tian University of Guelph, Environmental Sciences Ontario, Canada ttian01@uoguelph.ca Kwak, Jin-Hyeob University of Alberta, Renewable Resources Alberta, Canada jinhyeob@ualberta.ca Van Eerd, L.L University of Guelph, Environmental Sciences Ontario, Canada lvaneerd@uoguelph.ca Lychuk, Taras Brandon Research Centre, AAFC Manitoba, Canada taras.lychuk@agr.gc.ca Manns, Hida University of Guelph Ontario, Canada hmanns@trentu.ca Yang, Jingyi Greenhouse and Processing Crops Research Centre, AAFC Ontario, Canada jingyi.yang@agr.gc.ca Martel, Myra Lethbridge Research Centre, AAFC Alberta, Canada myra.martel@agr.gc.ca Zhao, Ying University of Saskatchewan, Soil Science Saskatchewan, Canada yzhaosoils@gmail.com Robbins, Naomi University of PEI, Canadian Rivers Institute Prince Edward Island, Canada robbins.n@gmail.com Session 14 Cambouris, Athyna Soil Crops Research and Development Centre (SCRDC), AAFC Québec, Canada athyna.cambouris@agr.gc.ca Panday, Dinesh Lincoln University, Agriculture and Environmental Sciences Minnesota, USA dinesh.panday239@my.lincoln.edu Congreves, Katelyn Agriculture and Agri-Food Canada Québec, Canada kcongrev@uoguelph.ca Périard, Yann Laval University, Soils and Agri-Food Engineering Québec, Canada yann.periard-larrivee.1@ulaval.ca Daei, Mohammad Ali Medical Doctor and Researcher in Biology Iran drdaei@gmail.com Seguel, Alex Universidad de la Frontera, Scientific and Technological Bioresource Temuco, Chile alex.seguel@ufrontera.cl Meriño-Gergichevich, Cristian BIOREN-UFRO, Universidad de La Frontera Temuco, Chile cristian.merino@ufrontera.cl Xu, Yan Université Laval Québec, Canada xuyan86313@gmail.com 271 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Session 15 Antoun, Hani Université Laval, département des sols et génie agroalimentaire & CRIV Québec, Canada hani.antoun.1@ulaval.ca Indraratne, Srimathie University of Peradeniya, Agriculture Peradeniya, Sri Lanka srimathipi@yahoo.ca Luo, Ling University of Hong Kong, Biological Sciences Hong Kong, China luoling@hku.hk Bekele, Asfaw Imperial Oil Resources Calgary, Canada asfaw.bekele@esso.ca Ngo, Thi Phuong Bioren centre, universidad de la Frontera Temuco, Chile ngophuongchimie@gmail.com Chan, Jaclyn University of Queensland, Mined Land Rehabilitation Ontario, Canada j.chan9@uq.edu.au Hossaini, Faiza University of Tehran Tehran, Iran fa_hosseini.90@ut.ac.ir Session 17 Buffet, Jean-Philippe INRS – Institut Armand-Frappier Québec, Canada jean-philippe.buffet@iaf.inrs.ca Nkongolo, Nsalambi Lincoln University of Missouri, Agriculture and Environmental Sciences Missouri, USA nkongolo@lincolnu.edu Civil, Nody Université Laval, département des sols et de genie agroalimentaire Québec, Canada nody.civil.1@ulaval.ca Trunov, Alexander Institute of Global Climate and Ecology Chita, Russia trunov88@bk.ru Elmi, Abdirashid Kathmandu University, Department of Environment and Tech Management Nepal a.elmi@ku.edu.kw 272 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Index 273 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Abail, Zhor – 173 Anderson, Lélia – 116 Barrett, Ryan – 92 Abalos, Diego – 63 Andronak, Lindsey – 79, 226 Barrington, Suzelle – 200 Abdellatif, Lobna – 157 Angers, Denis – 33, 34, 122, 142, 198 Basiliko, Nathan – 46, 119, 120, 125, 126, 158, 163, 168, 169, 170, 171 Abdelrahman, Hamada – 179 Abdi, Dalel – 55, 185, 186, 205 Abedin, Joinal – 108 Acuña, Jacquelinne – 160, 210 Adamchuk, Viacheslav – 87, 90, 194 Adamchuk-Chala, Nadiia – 90 Adelekun, Mayowa – 64 Ahmed, Hasan – 29 Ahmed, Naeem – 194 Airdesson Lima do Nascimento, Francisco – 181 Antoun, Hani – 108, 169, 242 Aoki, Shinsuke – 147 Aoyama, Masakazu – 173 Aparecido Mome Filho, Edison – 94 Baxi, Shailja – 134, 135 Bazghaleh, Navid – 49 Beauchemin, Karen – 99 Arcand, Melissa – 48, 210 Beckett, Peter – 108 Arenella, Mariarita – 48 Bedard-Haughn, Angela – 46, 83, 84, 220, 221 Arikawa, Hidetoshi – 147 Arrouays, Dominique – 180 Arseneault, Karin – 187 Arteaga, Jessica - 211 Ajmone Marsan, Franco – 131 Aspinall, Doug – 113, 114, 137 Akinremi, Wole – 64, 196 Astatkie, T. – 140 Alemu, Aklilu – 196 Aubin, Melanie – 60 Alfaro-Rodríguez, Ricardo – 89 Audette, Yuki – 129, 185 Alikhani, Hossein Ali – 244 Audinot, Nicolas – 38 Allaire, Suzanne – 110 Aulakh, Gurpreet – 158 Almas, Asgeir – 149, 150 Aurelio Carbone Carneiro, Marco – 159 Almeida, Gabriela – 58 Baumgartl, Thomas – 243 Bégin, Geneviève – 151 Bekele, Asfaw – 242 Bélanger, Gilles – 205 Bélanger, Nicolas – 119, 122 Bélec, Carl – 113 Bell, Terrence – 158 Bellenger, Jean-Philippe – 35, 140 Benbrahim, Mohammed – 168, 243 Benjannet, Rim – 37, 137 Bent, Elizabeth – 63 Ayumi Ishida, Débora – 177 Berg, Aaron – 232 Baah-Acheamfour, Mark – 65 Bernier-English, Valérie – 116 Babin, Doreen – 21 Bertrand, Normand – 198 Bandekar, Basanti – 159 Bhadha, Jehangir – 199 Banihashemi, Avid – 226 Bien, January – 148 Alves Ferreira, Doroteia – 159 Baraniya, Divyashri – 48 Bilošová, Hana – 130 Amadi, Chukwudi – 63, 195 Baranski, Marcin – 102 Bishop, Gary – 137 Amelung, Wulf – 69, 71, 165, 179 Bàrberi, Paolo – 102 Biswas, Asim – 87, 90, 94, 110, 190, 194, 224, 233 Alotaibi, Fahad – 158 Alotaibi, Khaled – 195, 237 Alvarez-Rivera, Oscar – 186 Alves Fernandes, Rafaela – 159 Amenc, Laurie – 52 Amendola, Andrea – 42 Amichev, Beyhan – 63 Barberis, Elisabetta – 152, 153 Barbieux, Sophie – 130 Barbosa Paulino, Helder – 159 Barnes, William – 123 Amiro, Brian – 196 274 Bittman, Shabtai – 99, 192, 196, 213 Bizarro, A. – 240 Bizimungu, Benoit – 137 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Blake, Ilze – 170 Buffet, Jean-Philippe - 247 Cennerazzo, Johanne – 38 Bloom, Paul – 51 Bulmer, Chuck – 88, 223 Chabbi, Abad – 107 Boahen, Stephen – 176 Bulot, Diane – 89, 116 Chai, Lilong – 99 Bochund, Christiane – 187 Bünemann, Else – 29, 68 Chalavi, Vida – 174 Bodineau, Guillaume – 206 Burrus, Vincent – 35 Champagne, Michel – 187 Boily, Carole – 116 Burton, David – 75, 92, 94, 124, 145, 214, 216 Chan, Jaclyn – 243 Bol, Roland – 69, 70, 71, 141, 174 Bork, Edward – 65 Borie, F. – 240 Bosch, Anna – 58 Bouroubi, Yacine – 113 Botula, Yves-Dady – 98 Boyko, Teak – 56 Boyle, Sean – 169 Buysse, Pauline – 83 Cade-Menun, Barbara – 55, 71, 72, 185, 186, 205, 206 Cai, Peng – 51 Calabi, Marcela – 35, 174, 175 Calder, Wayne – 66 Calotescu, Laura – 153 Cambareri, Sebastian – 197 Chanasyk, David – 43 Chang, Scott – 65, 111, 231 Chantigny, Martin – 33, 34, 75, 108, 144, 192, 197, 237 Chapman, Bill – 125 Charles, Anaïs – 198 Chaulk, Keith – 108 Checkmahomed, Liva – 187 Chelabi, Hakima – 59 Bower, Jennifer – 147 Cambouris, Athyna – 103, 136, 142, 227, 237 Chen, Chen – 74 Bradley, Robert – 124 Campbell, Con – 198 Chen, Huiming – 181 Brais, Suzanne – 119, 120, 121 Campbell, Daniel – 170 Chen, Wenli – 51 Brandt, Stewart – 231, 232 Campos, P. – 240 Chen, Xin – 133, 142 Brassard, Patrick – 106 Cao, Yanhong – 142 Cheng, Yi – 100 Braul, Larry – 229 Cao, Yu – 227 Cheng, Zonghqi – 164 Bremer, Eric – 226 Cappellen, Philippe Van – 226 Chevrier, David – 56 Brennan, Eric – 31 Carey, Sean – 219 Chezgi, Mehdi – 174 Brin, Claudia – 197 Carlyle, Cameron – 65 Chokmani, Karem – 103 Brin, Lindsay – 197 Caron, Jean – 116, 189, 219, 223, 239 Civil, Nody – 247 Brown, Lawrie – 207 Brown, Robin – 83, 221 Brown, Shannon – 62, 63 Bruno, Sebastien – 140 Bruulsema, Tom – 34, 115 Bruun, T. B. – 59 Bubier, Jill – 163 Buchmann, N – 29 Budjo, Floribert – 92, 248 Carson, Michael – 46, 158, 169 Cartes, Paula – 141 Caspersen, John – 120, 125 Castilla-Martinez, Mariela – 186 Cavalca, Lucia – 152 Cave, Mark – 57 Ceccherini, Maria Teresa – 48 Celi, Luisella – 23, 131, 152 275 Claessens, Annie – 142 Clark, Graham – 219 Colinet, Giles – 41, 130 Collin, Alexandre – 122 Condron, Leo – 35, 68, 174 Cooper, Julia – 102 Cooper, Miguel – 94 Congreves, Katelyn – 99, 198, 228, 237 Constant, Philippe – 160, 247 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Contreras, Francisco – 175 De Neergaard, A. – 59 El-Din Hassan, Saad – 158 Cooper, Pat – 207 Denes, Jérémy – 200 El Khoulali, Yasmina – 39 Córdoba, Alonso – 164 De Pue, Jan – 98 Ellert, B.H. – 53 Cormier, Julien – 116 Desjardins, Raymond – 99, 198, 237 Elliot, Jane – 229 Cornejo, P. – 240 Elmi, Abdurashid – 248 Cornelis, Wim – 98 Dessureault-Rompré, Jacynthe – 219 Engoke, Canon – 176 Côté, Benoít – 144 Dharmakeerthi, Saman – 110 Enid Martinez, Carmen – 52 Côté, Caroline – 135 Dias, Goretty – 196 Entz, Martin – 64, 102 Covarrubias, S. A. – 161 Dillingham, Randy – 190 Erskine, Peter – 243 Cowan, Elizabeth – 84, 175 Ding, Guo-Chun – 21 Estrada-Medina, Hector – 186 Cowling, Sharon – 211 Diochon, Amanda – 53 Evans, Leslie – 137, 185 Coyea, Marie – 122 Ditterich, Franziska – 45 Ewango, Corneille – 92, 248 Crolla, Anna – 202 Doerfer, Corina – 58 Fallon, Edith – 113 Curtis, Tony – 43 Dorais, Martine – 108, 169 Farenhorst, Annemieke – 69 Daei, Manizheh – 238 Drolet, Myriam – 168, 243 Farrell, Richard – 63, 195 Daei, Mohammad Ali – 238 Drouin, Pascal – 121 Faucon, Michel-Pierre – 41 Dai, Nancy – 148 Drury, Craig – 62, 66, 97, 115, 192, 197, 217, 230, 234 Fein, Jeremy – 51 Dalila Larios, Araceli – 201 Damar, Hada – 206 Dandeniya, Warshi – 244 Darnajoux, Romain – 35 Daroub, Samira – 199 Daugovesh, Oleg – 116 Davasse, Bernard – 107 David, Christophe – 102 Davidson Jewell, Mark – 140 Druschel, Gregory – 71 Dubé, Patrick – 201 Dunfield, Kari – 62, 63, 166, 212 Du Preez, C. C. – 165 Dupuis, Christian – 89 Durán, Paola – 160, 210 Dutta, Baishali – 99, 237 Fentabil, Mesfin – 66, 101 Ferrol, Nuria – 138 Fijalkowski, K. – 154 Fillon, Martin – 75 Fine, Aubrey – 52 Flaten, Don – 30, 69, 229 Flechard, Christophe – 83 Fleming, Rob – 125 Fliebach, Andreas – 102 DeBruyn, A. H. – 228 Dutton, Michael – 42, 57, 148, 154 Deen, Bill – 34 Duxbury, John – 20 Forge, Tom – 66 Deiana, Salvatore – 153 Dvorak, Joseph – 52 Fortier, Julien – 121 DeJunet, Alexis – 38 Dyck, Miles - 100 Fortin, Josée – 223 Delgado Cano, Beatriz – 201 Dynes, James – 51, 56, 188 Fortin, J. André – 74 Deliere, Laurent – 168 Egger, Keith N. – 47 Foudyl-Bey, Sara – 121 Demante, Rolando – 138, 141 Eivind Olesen, Jørgen – 180 Fraser, Tandra – 68, 161 Demin, Vladimir – 182 El-Ashry, Soad – 40 276 Fontaine, Laurent – 74 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Frossard, Emmanual – 29, 31, 68 Frutos, Roger – 39 Fuchs, Stephan – 102 Fugère, Martine – 124 Fujii, Kazumichi – 176 Fuller, Keith – 98, 137 Fulthorpe, Roberta – 168 Furze, Shane – 87 Gagnon, Daniel – 121 Gagnon, Jocelyn – 81 Gan, Qianjun – 187 Gan, Yantai – 49, 76, 157 Garcia Berumen, José Abraham – 161 Glenn, Aaron – 233 Godbout, Stéphane – 106, 201 Goltz, Doug – 30 González, Marcela – 30, 134, 135 Gonzalez Linares, Monica – 149 Halde, Caroline – 102 Hale, Beverley – 21, 42, 148, 152, 154 Halle, Cynthia – 71 Halley, John – 167 Gordon, Andrew – 166 Halloran, Samantha – 131 Gordon, Robert – 62, 191 Hamel, Chantal – 49, 76, 139, 157, 213, 214 Gorgolewski, Adam – 120, 168 Gorra, Roberta – 153 Gossen, Bruce – 231 Gottselig, Nina – 71 Goutouly, Pascal – 168 Gowda, Ankapura – 57 Gauthier, Mélanie – 187 Goyer, Claudia – 33, 75, 93 Gebala, Aurelia – 45, 162 Grandy, A. Stuart – 33 Genam Cuenca, Eduardo – 194 Grant, Brian – 99, 198, 237 Gendron, Laurence – 116 Grant, Cynthia – 69 Geng, Xiaoyuan – 90 Grayson, Sue – 212, 213 Georgallas, Alex – 95, 214 Greer, Charles – 76 George, Timothy – 207 Gregorich, Ed – 46, 53, 192, 202 Gervais-Beaulac, Vernhar – 220 Haas, Jessica – 243 Gopal, Achari – 155 Garnier, Patricia – 200 Germida, Jim – 76, 213 Gumiere, Silvio – 89, 116, 189, 219, 230, 239, 247 Grenon, Lucie – 113 Grewer, David – 229 Hanazawa, Shunsuke – 47 Hannam, Kirsten – 66 Hans, Geetkamal – 199 Hanson, Keith – 157 Hao, X. J. – 32 Haruna, Samuel – 136 Hashemi, Morteza – 202 Hauptmann, Matthieu – 243 Hawkins, Shawn – 164 Haygarth, Philip – 68, 70 Hayhoe, Doug – 24 Hazlett, Paul – 79, 119, 120, 125, 168 He, Jin-Sheng – 58 He, Ping – 230 He, Wentian – 230 Giagnoni, Laura – 48 Grimmett, Mark – 137, 145 Giles, Courtney – 71, 206, 207 Grishkan, Isabella – 163 Heck, Richard – 58, 80, 94, 227, 234 Gill, Ravinderpal – 234 Grobelak, Anna – 149, 150 Heinrich, Catherine – 243 Gillespie, Adam – 22, 46, 56, 76, 188 Grosser, A. – 148, 154 Heister, Katja – 21, 179 Grysan, Patrick – 38 Helgason, Bobbi – 46, 53, 76, 84, 210, 211 Gillis, Daniel – 38, 162 Giménez, Daniel – 94 Girard, Réjean – 60 Giweta, Mekonnen – 100 Gu, Ji-Dong – 245 Guallichand, Jacques – 59 Guertin, Claude – 247 Guo, Galen – 158, 163 Glen, Aaron – 101 277 Hemmingsen, Sean – 76 Hendershot, William – 42 Hepp, C. M. – 59 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Hernández-Hernández, Juan – 186 Isles, Peter – 71 Keiblinger, Katharina – 102 Ismail, Ashraf – 187 Keys, Kevin – 124 Hernandez Ramirez, Guillermo – 132 Izaurralde, Roberto – 232 Khafipour, Ehsan – 196 Heung, Brandon – 88, 223 Jamieson, Rob – 37, 39 Khiari, Lotfi – 37, 59, 137 Hijiri, Mohamed – 158 Janzen, Henry – 53, 76, 97, 99, 233 Khosravi, Kambiz – 56 Hill, Jane – 71, 206 Ho, Derrick – 88, 223 Hoballa, E. – 40 Hobson, Claire – 219 Hockaday, William – 189 Hodgson, Kyle – 217 Hoffman, Darrell – 216 Hogue, Richard – 77, 242 Hong, J. P. – 32 Hong, Zhineng – 182 Jayarathne, Kumudu – 30 Jayasundara, Susantha – 197 Jazestani, Jamshid – 165 Jeanne, Thomas – 77 Jennewein, Stephen – 199 Ji, Wenjun – 87, 194 Jiang, Xiaoqian – 69 Jiang, Yefang – 137, 141, 145 Jilling, Andrea – 33 Johnson, Eric – 231, 232 Kiani, Mina – 132 Kiba, D. – 29 King, Kevin – 115 King, Tom – 29 Kinsley, Chris – 202 Kirk, Ann – 231 Klavins, Maris – 221 Klumpp, Erwin – 69, 70, 71 Knight, Diane – 49 Knudby, Anders – 88 Jolivet, Claudy – 180 Kögel-Knabner, Ingrid – 21, 179 Jones, Marie-France – 93 Konschuh, Hannah – 46 Jones, Melanie – 66 Kotzé, Elmarie – 165 Jones, Trevor – 119, 120, 126, 168 Kovac, Radmila – 226 Hu, Yongfeng – 186 Huang, Bin – 133, 142 Jorge-Araujo, Priscila – 180 Huang, Qiaoyun – 51 Jorquera, Milko – 210 Huang, Shan – 74 Joseph, Stephen – 109 Huangfu, Yanchong – 164 Jouogo Noumsi, Christelle – 35 Kremer, Laurent – 243 Jouquet, Pascal – 245 Kröbel, Roland – 99, 198, 233 Joyner, Jessica – 164 Kroetsch, David – 80 Kacprzak, M. – 149, 150 Krumins, Janis – 221 Kandeler, Ellen – 45, 45, 162 Krzic, Maja – 213, 216 Kar, Gourango – 29, 132 Kulshresktha, Suren – 196 Karimi Karouyeh, Alireza – 94 Kumaragamage, Darshani – 30, 244 Hooker, Dave – 228 Horrigan, Emma – 119 Hossaini, Faiza – 244 Hrapovic, Leila – 233 Humphreys, Elyn – 24, 219 Hung, Truong Phuc – 39 Hunt, Derek – 213 Huot, Hermine – 164 Indraratne, Srimathie – 30, 244 Inostroza-Blancheteau, Claudio – 138 Inubushi, Kazuyuki – 47 Karppinen, Erin – 107 Ishii, Takaaki – 157 Katulanda, Panchali – 211 Isidório de Almeida, Ivarn – 181 Kaur, Jasmeen – 90 278 Knudby, Anders – 223 Kraemer, Stephan – 20 Kramer, Susanne – 45 Kranabetter, Marty – 125 Kuzmicz, Sarah – 76 Kwabiah, A. – 134 Kwak, Jin-Hyeob – 231 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Lafond, David – 168 Li, Haixiao – 31 MacDonald, Douglas – 99 Lafond, Jean – 104, 205, 214 Li, Huijie – 235 MacIntyre, Jane – 80 Lafond, Jonathan – 89, 219 Li, Huixin – 166 Macrae, Merrin – 115 Lafrance, Pierre – 151 Li, Jiuyu – 182 Madramootoo, Chandra – 194 Lafrenière, Melissa – 229 Li, Sheng – 93 Mafa-Attoye, Tolulope – 166 Laird, Amanda – 152 Li, Zhongyi – 182 Mafuka, Paul – 98 Lajeunesse, Julie – 205, 214 Li, Zhuoting – 230 Mahmoudabadi, Ebrahim – 94 Lambert, France – 121 Liénard, Amandine – 41 Mahy, Gregory – 41 Lamit, L. Jamie – 163, 171 Lilleskov, Erik – 163, 171 Makana, Jean-Remy – 92, 248 Lamoureux, Scott – 229 Lin, Lisa – 177 Makhani, Mitalie – 188 Landová, Hana – 130 Liot, Quentin – 160 Maldonado Vega, Maria – 161 Lang, Timothy – 199 Lisov, A. A. – 183 Malhi, S. S. - 100 Lange, Sébastien – 110 Little, Shannan – 99 Maltais-Landry, Gabriel – 31 Langenfeld, Aude – 168 Liu, Corey – 72, 206 Manns, Hida – 232 Langford, Cooper – 155 Liu, Jin – 186 Mapa, Ranjith – 110 Larmola, Tuula – 163 Liu, Ting – 166 Marhan, Sven – 45, 45, 162 Larney, Francis – 97 Liu, Zhaodong – 182 Maric, Mila – 227 Larouche, Jean-Pierre – 106 Lobb, David – 229 Martel, Myra – 99, 233 Lauverjon, Rodolphe – 206 Lokonda, Michel – 92, 248 Martin, Maria – 131, 152, 153 Lauzon, John – 34, 62, 197, 228 Lompo, F. – 29 Martin, Ralph – 185, 232 López-Diaz, Mariana – 186 Martinez, Carmen – 53 Lou, Kangyi – 111 Masoom, Hussain – 55 Lu, Caiyan – 133, 142 Masse, Jacynthe – 81, 212 Lucas, Yves – 177 Massicotte, Hugues – 47 Luiz Stürmer, Sidney – 159 Mathuthu, Manny – 41 Luke, Bainard – 213 Mat Su, Ahmad – 194 Lumsdon, David – 207 Matsuura, Yojiro – 176 Lavkulich, Les – 216 Layton, Alice – 164 Lee, Harold – 80 Lee, Lydia – 71 Leeson, Julia – 231 Leinweber, Peter – 22, 76 Leite Luiz, F.C. – 200 Lun, Olivia – 178 Matumoto-Pintro, Paula – 180 Lemke, Reynald – 198, 231, 232 Luo, Ling – 245 Matus, Francisco – 167, 178 Leon Castro, Leonardo – 133 Lupwayi, Newton – 103 Mbodj, Awa – 89, 116, 219 Létourneau, Guillaume – 116 Lychuk, Taras – 231, 232 Levesque, Vicky – 108, 242 Lynch, Derek – 68 Mbuyi Kakuni, Jean-Jacques – 92, 248 Ley, Lionel – 168 Ma, Bao-Luo – 188 Leyval, Corinne – 38 MacCormick, Elizabeth – 134 279 McConkey, Brian – 203, 233 McCormick, Ian – 212 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 McCray, Mabry – 199 Morissette, Samuel – 77 Nischwitz, Volker – 69, 70, 71 McDonald, Doug – 196 Morris, Dave – 125 Nkongolo, Nsalambi – 92 McGinn, Sean – 99 Moulin, Alan – 90, 101, 231, 232 Nlro, Elisa – 175 McShane, Heather – 42 Muananamuale, Carlos – 176 Nobel de Lange, Majimcha – 102 Muiznieks, Indrikis – 170 Noborio, Kosuke – 147 Munira, Sirajum – 69 Nogaret, Maguelone – 52 Munroe, Jake – 212 Noronha, Christine – 141 Merino, Carolina – 167, 178 Munroe, Paul – 109 Nowell, Peter – 137 Meriño-Gergichevich, Cristian – 238 Munson, Alison – 122 Noyce, Genevieve – 168 Murata, Alison – 153 Nsalambi, Nkongolo – 136, 201, 239, 248 Melfi, Aldolpho José – 177 Menasseri-Aubry, Safya – 200 Menezes-Blackburn, Daniel – 207 Messier, Christian – 122 Messiga, Aime – 131, 208 Metcalfe, Chris – 131 Muth, Theodore – 164 Muyumba Donato, Kaya – 41 Meyn, Thomas – 71 Myckytzuk, Nadia – 163, 170, 171 Mičová, Pavlína – 130 Naeth, M. Anne – 153, 231 Milczarek, M – 148 Naisse, Christophe – 107 Miller, Jim – 43, 192 Najat, Nassr – 168 Miniotti, Eleonora – 152 Najem, Mahdi – 135 Missong, Anna – 70 Nannipieri, Paolo – 48 Mitchell, Perry – 106 Napora, A. – 150 Mohammadi, Leila – 244 Nashon, Samson – 216 Mola, Magdi – 167 Navarro Borrell, Adriana – 76, 213 Mollier, Alain – 31, 206 Monger, Curtis – 233 Monokrousos, Nikolaos – 167 Monreal, Carlos – 30, 134, 135 Montalbán, Nicole – 139 Moore, Tim – 85, 163, 207 Mora, Maria de la Luz – 35, 138, 139, 141, 160, 174, 175, 210 Nwaichi, Eucharia – 40 Nyiraneza, Judith – 37, 137, 141, 145 Oberson, Astrid – 29, 68 Oh, Danny – 226 O’Halloran, Ivan – 129, 185, 228 Oliveira Filho, José Nilson – 181 Olfert, Owen – 231, 232 Olobatoke, Roseline – 41 Olson, Andrew – 97 Olson, Barry – 97 N’Dayegamiye, Adrien – 135 Ominski, Kim – 196 Nechi, Chaima – 136 Onyeike, Eugene – 40 Neczaj, Ewa – 148, 154 Opara, Lasbrey – 40 Neilsen, Denise – 66 Osawa, Akira – 176 Neilsen, Gerry – 66 Oswaldo Siqueira, José – 159 Nelson, Louise – 101, 199 Ouertani, Selmene – 169 Nernes, Attila – 98 Oufqir, Sofia – 51 Neufeld, Katarina – 213 Morales-Guadarrama, Andrés – 186, 240 Pace, Benjamin – 109 Neupane, Sara – 93 Pachepsky, Yakov – 25 Morel, Christian – 31, 206, 208 Nichol, Craig – 66, 101 Pageau, Denis – 34 Morier, Thomas – 103 Nikolajeva, Vizma – 170 Palacios, Joahnn – 106, 201 280 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Palma, Graciela – 178 Poblete, Patricia – 139, 141 Renella, Giancarlo – 48 Panday, Dinesh – 201, 239 Poirier, Vincent – 122 Rennert, Thilo – 162 Paré, David – 74, 120 Poll, Christian – 45, 45 Renneson, Malorie – 130 Paré, Maxime – 60 Portela, Mirya G.T. – 200 Reumont, Florian – 194 Paredes, Cecilia – 138 Porter, Timothy – 190 Parent, Léon-Étienne – 31, 55, 77, 136, 185, 198, 206, 240 Pourbabaee, Ahmad Ali – 244 Reyes-Diaz, Marjorie – 138, 238 Parkin, Gary – 227 Parnadeau, Virginie – 200 Parra, Leyla – 138 Pourhassan, Nina – 35, 140 Reynolds, Dan – 66, 97, 115, 192 Pourret, Olivier – 41 Rezanezhad, Fereidoun – 226 Prasher, Shiv – 38, 165 Prescott, Cindy – 125, 212 Peak, Derek – 29, 32, 56, 65, 132, 188 Preusser, Sebastian – 45 Pei, Chengyin – 139 Price, Gordon – 37, 38, 39, 56, 95, 131, 134, 140, 159, 162, 214 Peigné, Joséphine – 102 Pelletier, Vincent – 117 Peltre, Clément – 243 Peng, Xiaochun – 74 Pennock, Dan – 123 Pepin, Steeve – 169, 223 Perdrial, Nicolas – 147 Peria Cabriales, Juan José – 161 Pronk, Geertje J. – 21, 179 Puglisi, Edoardo – 48 Purton, Kendra – 123 Puurveen, Dick – 100 Quideau, Sylvie – 26, 100, 123, 212 Quiquampoix, Hervé – 39, 52, 180 Raeini-Sarjaz, Mahmoud – 202 Périard, Yann – 189, 239 Raghavan, Vijaya – 106 Perreault, Lili – 119 Rahemtulla, Farid – 72 Perron, Isabelle – 142, 227 Ramata-Stunda, Anna – 170 Petrina, Zaiga – 170 Rampon, Jean Noel – 206 Piché-Choquette, Sarah – 160 Rawluk, Christine – 196 Piché, Yves – 74 Redel, Yonathan – 139, 141 Pichette, Jennifer – 169 Reeb, Mary-Anne – 115 Pietramellara, Giacomo – 48 Reedyk, Sharon – 43 Pimentel, Rejane – 58 Rees, Frédéric – 109 Pinsonneault, Andrew – 85, 207 Regier, Tom – 56, 188 Phuong Ngo, Thi – 107, 245 Placek, A. – 149, 150 Regina Montes, Célia – 177 Reid, Anya – 125 Reid, Keith – 98, 190 Plante, Alain – 175, 189, 243 281 Ribeiro Pereira, Osvaldo José - 177 Riedel, Kathrin – 102 Robbins, Naomi – 141 Robinson, Clare – 226 Rochette, Philippe – 23, 33, 108, 198, 237 Rodd, Vernon – 137, 145 Rodrigo Leiva, Fabio – 89 Romário Uchóa, Luiz – 181 Rornani, Marco – 152 Roulet, Nigel – 85 Rousseau, Alain N. – 189, 239 Roy, Amal – 34, 101 Roy, Julie – 242 Royer, Isabelle – 142 Ruiz De Le Macorra, Francisco – 194 Rumpel, Cornelia – 35, 107, 174, 245 Rutherford, P. Michael – 47 Rutila, Elizabeth – 71 Saby, Nicolas – 180 Sader, M. – 40 Saggin-Junior, Orivaldo Jose – 159 Said Pullicino, Daniel – 152 Saint-Laurent, Diane – 220 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Samson, Marie Elise – 223 Shipley, Bill – 140 Stara, Kalliopi – 167 Sanborn, Paul – 72 Shu, Weixi – 37, 95 Sandhage-Hofmann, A. – 165 Si, Bing – 235 Staunton, Siobhan – 39, 52, 180 Sanson, Nicolas – 77 Siciliano, Steven – 107, 152 Santos, Cristian Franca – 181 Sidhu, Savitoz – 190, 233 Saraiva, Irondino – 176 Siebers, Nina – 69, 179 Saville, Barry – 139 Siemens, Jan – 70, 71 Scandellari, Francesca – 75 Signor, Diana – 200 Schloter, Michael – 21 Sik Ok, Yong – 111 Schmidt, Karsten – 58 Silamikele, Baiba – 170 Schmidt, Margaret – 88, 216, 223 Silamikele, Inese – 221 Schmidt, Michael – 52, 53 Schneider, Kim – 68 Schneider, Thomas – 102 Schoenau, Jeff – 29, 32, 132, 195, 226 Scholten, Thomas – 58 Schroeder, William – 220 Schroth, Andrew – 71 Simard, Marie-Josée – 151 Simpson, Andre – 55, 106 Simpson, Myrna – 55, 72, 106, 177, 178, 190, 229 St-Arnaud, Marc – 158 Stewart, Katherine – 107 Stewart, Kayla – 108 Stiles, Kyra – 92 St. Luce, Mervin – 143 Stone, Maddie – 189 Strukelj, Manuella – 120 Stutter, Marc – 207 Sukdeo, Nicole – 47 Sulaiman, Muhammad – 62 Sunahara, Geoffrey – 149 Surani Chathurika, J. A. – 244 Singh, Bal Ram – 149, 150 Surridge, Ben – 70 Singh Dhillon, Gurbir – 65 Swallow, Matthew – 123 Singh, Jessica – 202 Sweeney, Stewart – 113, 114, 137 Singh, Maninder – 199 Smalla, Kornelia – 21 Taghizadeh-Toosi, Arezoo – 180 Smeaton, Christina – 226 Tagliavini, Massimo – 75 Scow, Kate – 31 Smenderovac, Emily – 125, 170 Taherymoosavi, Sarasadat – 109 Seguel, Alex – 240 Smith, Ward – 99, 198, 237 Takahashi, Maasa – 47 Selmi, Hela – 169, 242 Smukler, Sean – 213 Taki, Rezvan – 191 Shaaf, Wolfgang – 231 Sodano, Marcella – 152 Tamburini, F. – 29 Shahariar, Md Shayeb – 220 Soolanayakanahally, Raju – 220 Tan, Chin – 32, 194 Schwertfeger, Dina – 42 Schwingharner, Timothy – 42 Shahnazari, Ali – 202 Shand, Charles – 207 Sharifi, Mehdi – 131, 139, 143, 144 Shaw, Richard – 164 Soon, Yoong – 103 Soong, Ronald – 106 Sooriya Arachchilage, Kishari – 226 Tar’an, Bunyamin – 49 Tatti, Enrico – 75 Teen, Ewing – 47 Tenni, Daniele – 152 Spence, Jennifer – 214 Tenuta, Mario – 64, 196 Shi, Yi – 133, 142 Spiers, Graeme – 108, 158, 169, 171 Tete, Emmanuel – 83 Shi, Yichao – 205, 208, 214 Spokas, Kurt – 26 Shabaga, Jason – 126 282 Thériault, Georges – 151 Thevathasan, Naresh – 166 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Thevenin, Nicolas – 243 Van Ranst, Eric – 98 Wang, Xueming – 203 Thiffault, Nelson – 74 Van Rees, Ken – 63, 65, 79, 195 Wang, Ying – 32, 70 Thiollet-Scholtus, Marie – 168 Vanrobaeys, Jason – 229 Wang, Yongzhuang – 133, 142 Thomas, Ben – 143, 144 Vasiluk, Luba – 42, 57, 148 Wang, Yu – 208 Thompson, Aaron – 175 Vasseur, Claire – 81 Watson, Kent – 123 Thompson, Barry – 37 Velasquez, Gabriela – 35, 141, 174, 175 Watters, Nicolas – 116 Thompson, Karen – 63 Thorn, Ryan – 154 Tian, Tian – 234 Tikasz, Peter – 144 Toner, Brandy – 51 Torne, Elisabetta – 75 Traoré, O.Y.A. – 29 Tran, Honghi – 119, 120, 168 Tremblay, Gaëtan – 185 Tremblay, Gilles – 135 Tremblay, Nicolas – 113, 237 Trémier, Anne – 200 Truax, Benoit – 121 Trunov, Alexander – 249 Tsiakiris, Rigas – 167 Turner, Benjamin – 35 Vellend, Mark – 124 Vereecken, Harry – 69, 71 Vialykh, Elena – 155 Viaud, Valérie – 83 Vickers, Stephanie – 137 Vidana Gamage, Duminda – 110 Vieira Batista, Marcos Antonio – 181 Vigneault, Philippe – 113 Violante, Antonio – 153, 174 Viscardi, Sharon – 160 Viscarra Rossel, Raphael – 25 Vitousek, Peter – 31 Voegel, Tanja – 101, 199 Vogel, Cordula – 21 Weber, Kela – 134, 135 Webster, Kara – 125 Weiseth, Blake – 32 Welacky, Tom – 32 Wendler, Renate – 207 Wertz, Sophie – 75, 197 Westbrooke, Cherie – 84 Westphal, Megan – 64 Wichard, Thomas – 35 Wilhartitz, Inés – 102 Willbold, Sabine – 69, 70 Wilson, Henry – 90, 101, 233 Whalen, Joann – 90, 133, 135, 143, 144, 149, 166, 173, 188, 190, 194, 198 Whitney, Sean – 93 Whittaker, Jennifer – 145 Voroney, Paul – 68, 129, 134, 185 Williams, Dan – 164 Wagai, Rota – 22 Williams-Johnson, Shanay – 171 Wagner-Riddle, Claudia – 34, 62, 63, 99, 191, 197, 202 Wilson, Mike – 164 Walker, Forbes – 164 Wloka, D. – 148, 150 Walker, Roxanne – 164 Worwag, M. – 148, 154 Wall, D. H. – 161 Wragg, Joanna – 57 Walley, Fran – 211 Wu, Huayong – 51 Wang, Lei – 208 Xu, Jianming – 181 Van Eerd, Laura – 228 Weng, Meng – 207 Xu, Renkou – 182 Van Heyst, Bill – 62 Wang, Sheng-qiang – 208 Xu, Yan – 240 Van Loon, Lisa – 42 Wang, Xiaoyue – 84 Xu, Yaoyang – 71 Upamali Rajapaksha, Anushka – 111 Vaillancourt, Mathieu – 34 Vanasse, Anne – 34 Van Bochove, Eric – 151 VandenBygaart, Bert – 46, 198, 203 Van den Heuvel, Michael – 141 VanderZaag, Andrew – 62, 99, 191, 202 283 Soil Interfaces for Sustainable Development Program, 5th – 10th July, 2015 Yang, Jianjun – 186, 192 Zanzo, Elena – 152, 153 Zhang, Zhidan – 221 Yang, Jingyi – 97, 115, 217, 234 Zavarzin, A. A. – 183 Zhang, Yu – 39 Yang, Xueming – 66, 97, 115, 192, 234 Zavarzina, Anna – 182, 183 Zhao, Muqiu – 142 Zebarth, Bernie – 75, 92, 93, 143, 145, 197, 214 Zhao, Xu – 208 Yannikos, Nils – 195 Yates, Thomas – 217 Yergeau, Étienne – 76, 158 Young, Michelle – 242 Zaghloul, Alaa – 40 Zagoskina, Natalia – 182, 183 Zhao, Yajie – 133 Zechmeister-Boltenstern, Sophie – 102 Zhao, Ying – 235 Zegan, Dan – 106, 201 Zhou, Wei – 230 Zhang, Jin – 223 Zhu, Xinyu – 181 Zhang, Tiequan – 32, 98, 194 Ziadi, Noura – 31, 55, 108, 142, 143, 185, 205, 206, 208, 214, 227, 237, 240 Zhang, Yakun – 87, 224 284
