Effect of mechanical and biological enhancements on erosion at high elevation disturbed lands by Susan Rhea Winking A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Land Rehabilitation Montana State University © Copyright by Susan Rhea Winking (2002) Abstract: The objective of this study was to evaluate the effect of erosion control measures on sediment yields on reclaimed steep slopes at the Treasure Mine, MT and compare measured sediment yields to values predicted by Revised Universal Soil Loss Equation (RUSLE) Version 1.06. Plots were constructed on a regraded waste rock area having a uniform 25 % slope. Five treatments were replicated three times in a completely randomized design. Treatments applied were no coversoil, 30 cm coversoil, 30 cm coversoil/pitting of the soil surface, 30 cm coversoil/tree slash barriers, and 30 cm of coversoil/vesicular-arbuscular mycorrhizal (AM) fungi inoculum. Plots received identical application of seed and fertilizer. Total annual sediment yields for test plots were low during 2000 (mean 0.11 Mg/ha) and increased in 2001 (mean 1.17 Mg/ha). There were no differences in mean sediment yield by treatment in both years. There was a trend on pitted slopes for lower sediment yield in 2000 and significantly lower rill severity rating in 2001. Results suggest that pitting of the soil surface is potentially an effective erosion control practice at the level of precipitation received during the study, preventing rill formation and reducing sediment yields on steep slopes until vegetation can provides adequate slope stability. Plant growth was significantly lower on the no coversoil treatment, but there were no differences between those remaining treatments that received 30 cm of coversoil. Prior to implementation of field treatments, Sorghum Sudanese grown in the greenhouse in coversoil and waste rock material collected before application of AM inoculum had 39 % and 30 % AM root colonization levels, respectively. After two growing seasons, there were no significant differences in percent AM root colonization of Hordeum vulgare harvested from no coversoil (34 %), coversoil (34 %), and coversoil/AM inoculum (35 %) treatments. Agropyron trachycaulum harvested from AM inoculum treated plots showed significantly higher AM colonization levels (53 %) compared to the non-inoculated coversoil (46 %) and no coversoil treatments (44 %). AM inoculation treatment did not enhance aboveground plant growth. Although RUSLE version 1.06 overpredicted mean sediment yields by 0.2 ± 0.2 Mg/ha during 2000 and underpredicted by 1.0 ± 1.0 Mg/ha in 2001, estimates of sediment yields were close to actual sediment yields. Rill formation factor constants were applied to the 2001 data when rilling was moderate or greater, which improved RUSLE’s ability to predict sediment yield to within 97 % of measured sediment yield. The sediment-delivery ratio was 0.14 for the coversoil/pitting treatment and 0.60 for the coversoil/slash barriers. EFFECT OF MECHANICAL AND BIOLOGICAL ENHANCEMENTS ON EROSION AT HIGH ELEVATION DISTURBED LANDS by Susan Rhea Winking A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Land Rehabilitation MONTANA STATE UNIVERSITY Bozeman, Montana July, 2002 V Jl^u APPROVAL of a thesis submitted by Susan Rhea Winking This thesis has been read by each member of the thesis committee and has been found to be satisfactory regarding content, English usage, format, citations, bibliographic style, and consistency, and is ready for submission to the College of Graduate Studies. Douglas J. DoIlhop/ ? ) /}. Q 6 ^ % % / Ij a p o j. Approved for the Department of Land Resources & Environmental Sciences Jeffrey S. Jacobsen ignature) Date Approved for the College of Graduate Studies Bruce R. McLeo (Signature) Date iii STATEMENT OF PERMISSION TO USE In presenting this thesis in partial fulfillment of the requirements for a master's degree at Montana State University, I agree that the Library shall make it available to borrowers under rules of the Library. If I have indicated my intention to copyright this thesis by including a copyright notice page, copying is allowable only for scholarly purposes, consistent with “fair use” as prescribed in the U.S. Copyright Law, Requests for permission for extended quotation from or reproduction of this thesis in whole or in parts may be granted only from the copyright holder. Signature iv ACKNOWLEDGEMENT I would like to thank Barretts Minerals, Inc. and PHC Reclamation for providing funding for this research. I would also like to thank my committee members, Rick Fasching, Paul Hook and especially Catherine Zabinski for her guidance and expertise on the mycorrhizal fungi aspect of this research. Special appreciation is extended to my major advisor, Douglas Dollhopf, for his knowledge and experience in the development and refinement of reclamation science. I dedicate this work to my daughter, Annabelle Winking. TABLE OF CONTENTS LIST OF TABLES...................................................................................................... vii LIST OF FIGURES.................... .............................!................................. ................ xiii ABSTRACT................................................................................................................ xiv 1. INTRODUCTION...................................................................................................... I 2. LITERATURE REVIEW........................................................................................... 3 <0. OO <1 Erosion Control Regulations....................................................................................... 3 Revised Universal Soil Loss Equation (RUSLE)........................ 3 R - Rainfall/Runoff Erosivity......... K —Soil Erodibility......................... LS - Hillslope Length and Gradient C - Cover-Management.................. P - Support Practices......................................................................................... 10 Improved Accuracy in Representing Effect of Slope Steepness....... '............... 11 RUSLE and Geomorphology........................................................... 12 Database Sensitivity of RUSLE......................................................................... 12 Use of RUSLE on High Elevation, Steep Slopes.............................................. 13 Commercial Mycorrhizal Fungi Inoculations in Mineland Reclamation..................14 3. METHODOLOGY................................................................................................... 16 Site Description ...... 16 Experimental Design................................................................................................. 17 Sediment Collection Trough Design......................................................................... 18 Seeding Mix and Seeding Procedures....................................................................... 18 Commercial AM Inoculum Application Procedures ......................................., 20 Data Collection and Analysis.......... .............. 21 Spoil Backfill and Coversoil Physiochemical Analysis........................... 21 Precipitation and Evaporation Measurements...................................................21 Runoff Collection Methods................................ 22 Sediment Collection Methods............................................................................22 Rill Classification Methods................................................................................24 Plant Measurements........................................................................................... 25 Pre-Inoculation AM Colonization Levels of Coversoil and Spoil Backfill Material....................................................................................... 26 Percent Colonization by AM Fungi Procedures................................................ 26 TABLE OF CONTENTS continued Mycorrhizal Infection Study.............................................................................. 27 Statistical Analysis............................................................................................. 27 RUSLE v.1.06 Computer Model Analysis........................................................ 28 Hillslope Area Calculations............................................................................... 29 4. RESULTS AND DISCUSSION............................................................................... 31 Coversoil and Spoil Backfill PhysiochemicalCharacteristics................................... 31 Sediment Yields on High Altitude Steep Slopes...................................................... 32 Effect of Mechanical and Biological Erosion Control Measures on Sediment Yield.................................................................................. 33 Effect of Rill Severity Class on Sediment Yield...............................................34 Effect of Precipitation on Sediment Yield......................................................... 36 Effect of Rock Cover on Sediment Yield, Plant Biomass, Runoff and Rill Severity........................................................................................... 39 Runqff on High Altitude Steep Slopes.................................... 40 Effect of Runoff on Sediment Yield and Rill Severity Class............................ 40 Plant Growth on High Altitude, Steep Slopes.......................................................... 42 Effect of Erosion Control Measures on Plant Growth Characteristics..............42 Effect of Plant Growth on Sediment Yield, Runoff and Rill Severity Class..................................... 43 Pre-Inoculation Mycorrhizal Infectivity Potential............................................. 44 Effect of AM inoculum on Colonization Levels m Agropyron trachycaulum and Hordeum vulgare.................................................... 44 Ability of Measured Factors to Predict Sediment Yield and Runoff........................45 Ability of RUSLE v.1.06 to Predict Sediment Yields at High Elevation Sites........47 Measured Sediment-Delivery Ratios for Pitting and Slash Barrier Treatments............................................................................................. 48 5. SUMMARY AND CONCLUSIONS....................................................................... 51 REFERENCES CITED.............................................................................................. ,...56 APPENDICES.......................... APPENDIX A APPENDIX B APPENDIX C APPENDIX D APPENDIX E - 60 Soil Physiochemical Data....................................................... 61 Precipitation Data............................................................... ,...63 Sediment Yield and RunoffData.............................. 77 Vegetation Data...................................................................... 84 Statistical Analysis............................................. 100 vii LIST OF TABLES Table Page 1. Examples of Montana legislation mandating erosion control......................................4 2. Seed mix and application rate on test plots................................................................20 3. Soil physiochemical analytical methods....................................................................21 4. Soil erosion condition classification for rills..............................................................24 5. Input variables for RUSLE version 1.06.................................................................... 28 6. Coversoil and spoil backfill physiochemical characteristics..................................... 31 7. Mean sediment yield by treatment during 2000 and 2001......... ............................... 34 8. Mean rill severity class by treatment during 2000 and 2001 ....... ............................. 34 t 9. Mean sediment yield and precipitation across all treatments for two-week periods during 2000 and 2001....................................................................................36 10. Strength of relationship of total precipitation, maximum daily precipitation, and maximum hourly precipitation to mean Sediment yield across all treatments for tWo-week periods during 2000 and 2001............................ 37 11. Mean percent rock cover by treatment during 2001 ........................... ...................... 39 12. Strength of relationship of percent rock cover to sediment yield, biomass, runoff and rill severity class during 2001 ..................................................................40 13. Mean annual runoff (m3/ha) by treatment during 2000 and 2001............................. 40 14. Strength of relationship of runoff to sediment yield and rill severity class during 2000 and 2001 .............................. ................................................. ............... 42 15. Mean plant growth characteristics by treatment during 2001....................................42 16. Strength of relationship of plant growth characteristics to sediment yield, runoff and rill severity class during 2001 .............................................................................43 17. Mean percent pre-inoculation AM colonization levels in the coversoil and spoil backfill material during 2000........................ ............................................................ 44 V lll LIST OF TABLES - continued Table -n Page 18. Mean percent AM colonization levels of Hordeum vulgare and Agropyron trachycaulum during 2001......................................................................................... 45 19. Multiple linear regression analysis results using measured factors to predict sediment yield and runoff during 2000 and 2001..................................................... 46 20. RUSLE predicted and measured sediment yield values (Mg/ha) for all test plot treatments during 2000 and 2001.................................................................47 21. Optimized RUSLE sediment yields (Mg/ha) using rill formation factors during 2001................................................................................................................ 491 22. Measured sediment-delivery ratio values for Coversoil/Pitting and Coversoil/Slash Barrier treatments.............. *............................................................ 50 23. Coversoil textural analyses.........................................................................................62 24. Coversoil pH and EC analyses....................................................................................62 25. Subsoil textural analyses.................................. 62 26. Subsoil pH and EC analyses................................................ 62 27. Monthly precipitation (cm) for Dillon, Montana (WMCE), 2000................. 64 28. Monthly precipitation (cm) for Dillon, Montana (WMCE), 2001..............................65 29. Precipitation (cm) at Treasure Mine, June 20 -30,2000.............................................66 30. Precipitation (cm) at Treasure Mine, July 2000..........................................................67 31. Precipitation (cm) at Treasure Mine, August 2000.................................................... 68 32. Precipitation (cm) at Treasure Mine, September 2000...............................................69 33. Precipitation (cm) at Treasure Mine, October I - October 10,2000..........................70 34. Precipitation (cm) at Treasure Mine, May 4 - May 31,2001.....................................71 V ix LIST OF TABLES - continued Table Page 35. Precipitation (cm) at Treasure Mine, June 2001.............................................. 72 36. Precipitation (cm) at Treasure Mine, July 2001..........................................................73 37. Precipitation (cm) at Treasure Mine, August 2001.................................................... 74 38. Precipitation (cm) at Treasure Mine, September I -17,2001.................... 75 39. Evaporation (cm) at Treasure Mine, 2000 and 2001 ............................ .................... 76 40. Sediment yield (kg) on test plots, 2000......................................................................78 41. Sediment yield (kg) on test plots, 2001......... ............... ........................ ;.................. 79 42. Depth (cm) of runoff in troughs at test plots, 2000.....................................................80 43. Depth (cm) of runoff in troughs at test plots, 2001.....................................................81 44. Rill severity (class) on test plots, 2000.......................................................................82 45. Rill severity (class) on test plots, 2001.......................................................................83 46. Perennial grass canopy cover (%) on test plots, 2001.............................................. 85 47. Forb canopy cover (%) on test plots, 2001 ................................................................86 48. Annual grass canopy cover (%) on test plots, 2001....................................................87 49. Perennial grass basal cover (%) on test plots, 2001....................................................88 50. Forb basal cover (%) on test plots, 2001................................................................. 89 51. Annual grass basal cover (%) on test plots, 2001............................. ........................ 90 52. Rock cover (%) on test plots, 2001......................................................................... 91 53 . Bare ground cover (%) on test plots, 2001..... ........................................................... 92 54. Perennial grass biomass (g) on test plots, 2001 93 LIST OF TABLES - continued Table Page 55. Forb biomass (g) on test plots, 2001..........................................................................94 56. Annual grass biomass (g) on test plots, 2001................. ........................................... 95 57. Vegetative litter cover (class) on test plots, 2001......................................................96 58. Percent colonization by vesicular arbuscular mycorrhizal fimgi in coversoil and spoil backfill material, 2000.................................................................................97 59. Percent colonization by vesicular arbuscular mycorrhizal fungi in Hordeum vulgare, 2001.................................................................................. ...98 60. Percent colonization by vesicular arbuscular mycorrhizal fungi m Agropyron trachycaulum, 2001.....................................................................................................99 61. Two way analysis of variance of sediment yield, 2000............................................ 101 62. Two way analysis of variance of sediment yield, 2001............... 103 63. Two way analysis of variance of rill severity class, 2000.......... 104 64. Two way analysis of variance of rill severity class, 2001............................. 106 65. Linear regression of mean rill severity class on total annual sediment yield, 2000...108 66. Linear regression of mean rill severity class on total annual sediment yield, 2001 ...109 67. Linear regression of total precipitation on total annual sediment yield, 2000......... 110 68. Linear regression of maximum daily precipitation on total annual soil loss,2000 ................................................................................................................. H I 69. Linear regression of maximum hourly precipitation on total annual soil loss, 2000........................................... 112 70. Linear regression of total precipitation on total annual sediment yield, 2001...........113 71. Linear regression of maximum daily precipitation on total annual sediment yield, 2001............................................................................................ ,....114 LIST OF TABLES - continued Table Page 72. Linear regression of maximum hourly precipitation on total annual sediment yield, 2001 .............................................................................................. 115 73. Two way analysis of variance of percent rock cover during 2001........... ................ 116 74. Linear regressionof percent rock cover on sediment yield, 2001...............................117 75. Linear regressionof percent rock cover on biomass, 2001........................................ 118 76. Linear regressionof percent rock cover on total annual runoff, 2001........................119 77. Linear regression of percent rock cover on rill severity class, 2001..........................120 78. Two way analysis of variance of runoff (m3/ha), 2000............................................ 121 79. Two way analysis of variance of runoff (m3/ha), 2001............................................ 122 80. Linear regression of runoff on sediment yield, 2000................................................ 123 81. Linear regression of runoff on sediment yield, 2001................................................ 124 82. Linear regression of runoff on mean rill severity class, 2000...................................125 83. Linear regression of runoff to mean rill severity class, 2001...................................126 84. Two way analysis of variance on biomass (kg/ha), 2001................ 127 85. Two way analysis of variance on percent canopy cover, 2001................................ 129 86. Two way analysis of variance on percent basal cover, 2001 ................................... 131 87. Linear regression of biomass (kg/ha) on sediment yield, 2001................................. 133 88. Linear regression of percent canopy cover on sediment yield, 2001 ....................... 134 89. Linear regression of percent basal cover on sediment yield, 2001 .......................... 135 90. Linear regression of biomass (kg/ha) on runoff, 2001 ......................................... 136 91. Linear regression of percent canopy cover on runoff, 2001 137 \ xii LIST OF TABLES - continued Table " Page 92. Linear regression of percent basal cover on runoff, 2001........................................ 138 93. Linear regression of biomass (kg/ha) on rill severity, 2001..................................... 139 94. Linear regression of percent canopy cover on rill severity, 2001 ......... ................... 140 95. Linear regression of percent basal cover on rill severity, 2001................................. 141 96. Multiple linear regression of runoff, mean rill'severity class and slope area on sediment yield, 2000............... ............................................................................ 142 97. Multiple linear regression of rill severity class, runoff, slope area, biomass, canopy cover, basal cover and rock cover on sediment yield, 2001......................... 143 98. Multiple linear regression of rill severity class and slope area on runoff, 2000.......145 99. Multiple linear regression of mean rill severity class, slope area, biomass, canopy cover, basal cover and rock cover on runoff, 2001....................................... 146 100. Multiple linear regression of maximum hourly precipitation, increase in rill severity class and runoff on sediment yield, 2000 and 2001.............................148 101. T-test of mean percent AM colonization levels in the coversoil and spoil backfill material during 2000................................................................... 149 102. Two way analysis of variance of percent AM colonization levels VhHordeum vulgare, 2001....................................................................................... 150 103. Two way analysis of variance of percent AM colonization levels in Agropyron trachycaulum, 2001........................................................................... :..152 Xiii LIST OF FIGURES Figure Page 1. Location of study site in southwest Montana............................................................16 2. Design and layout of test plots at the Treasure Mine, MT........................................19 3. Calculation to convert water depth in trough into volumetric measure....................23 4. Schematic of dimensions used to calculate area contributing to runoff and sediment yield on pitted treatment plots...........................................................30 5. Comparison of mean annual sediment yields for by treatment during 2000 and 2001................................ ....................................................... :.......................... 32 6. Strength of relationship of mean rill severity class to total annual sediment yield during 2000 and 2001 ......................................................................;...... ....... 35 7. Comparison of total precipitation and mean sediment yield across all treatments for two-week periods during 2000 and 2001........ ......................... ,........................ 38 8. Comparison of mean sediment yield and runoff by treatment during 2000 and 2001...................................................................................................................41 9. Comparison of measured, RUSLE predicted, and optimized RUSLE sediment yields using rill formation factors on test plots during 2001.....................49 xiv ABSTRACT The objective of this study was to evaluate the effect of erosion control measures on sediment yields on reclaimed steep slopes at the Treasure Mine, MT and compare measured sediment yields to values predicted by Revised Universal Soil Loss Equation (RUSLE) Version 1.06. Plots were constructed on a regraded waste rock area having a uniform 25 % slope. Five treatments were replicated three times in a completely randomized design. Treatments applied were no coversoil, 30 cm coversoil, 30 cm coversoil/pitting of the soil surface, 30 cm coversoil/tree slash barriers, and 30 cm of coversoil/vesicular-arbuscular mycorrhizal (AM) fungi inoculum. Plots received identical application of seed and fertilizer. Total annual sediment yields for test plots were low during 2000 (mean 0.11 Mg/ha) and increased in 2001 (mean 1.17 Mg/ha). There were no differences in mean sediment yield by treatment in both years. There was a trend on pitted slopes for lower sediment yield in 2000 and significantly lower rill severity rating in 2001. Results suggest that pitting of the soil surface is potentially an effective erosion control practice at the level of precipitation received during the study, preventing rill formation and reducing sediment yields on steep slopes until vegetation can provides adequate slope stability. Plant growth was significantly lower on the no coversoil treatment, but there were no differences between those remaining treatments that received 30 cm of coversoil. Prior to implementation of field treatments, Sorghum Sudanese grown in the greenhouse in coversoil and waste rock material collected before application of AM inoculum had 39 % and 30 % AM root colonization levels, respectively. After two growing seasons, there were no significant differences in percent AM root colonization of Hordeum vulgare harvested from no coversoil (34 %), coversoil (34 %), and coversoil/AM inoculum (35 %) treatments. Agropyron trachycaulum harvested from AM . inoculum treated plots showed significantly higher AM colonization levels (53 %) compared to the non-inoculated coversoil (46 %) and no coversoil treatments (44 %). AM inoculation treatment did not enhance aboveground plant growth. Although RUSLE version 1.06 overpredicted mean sediment yields by 0.2 ± 0.2 Mg/ha during 2000 and underpredicted by 1.0 + 1.0 Mg/ha in 2001, estimates of sediment yields were close to actual sediment yields. Rill formation factor constants were applied to the 2001 data when rilling was moderate or greater, which improved RUSLE's ability to predict sediment yield to within 97 % of measured sediment yield. The sediment-delivery ratio was 0.14 for the coversoil/pitting treatment and 0.60 for the coversoil/slash barriers. I I. INTRODUCTION An integral part of land reclamation Best Management Plans (BMPs) is a combination of management and structural practices to control erosion hazards resulting from soil disturbance. BMPs can ihclude erosion control activities such as increasing surface roughness of the soil, mulch incorporation, and terraces (Toy & Foster, 1998). These mechanical erosion control measures are routinely used on many mined lands and construction sites to provide short-term and long-term stability to disturbed areas and minimize or eliminate of&site impacts (Toy & Foster, 1998). Erosion hazards increase when vegetative cover is lost, soil permeability is low, and the ground increasingly slopes, especially if soils are shallow (Brooks et al., 1997). Good vegetative cover ideally reduces erosion hazards, but the development of adequate plant cover may be difficult due to the short growing season, an often thin, nutrient-poor, rocky soil resource, and mining practices. At higher elevations, soil erosion is dominated by spring precipitation or runoff events including snowmelt, rain on snow, and thawing soils. Soils are particularly susceptible to erosion when the frost layer recedes below surface during spring thaw. The frost layer still prevents water infiltration and generates ruhoff but leaves the thawed layer vulnerable to detachment and soil loss, which directly affects vegetative establishment especially during initial years after reclamation begins (Toy & Foster, 1998). This research focuses on mechanical practices that reduce the energy of flowing water and biological enhancements to stimulate vegetative growth to reduce soil erosion on high elevation steep slopes. 2 Investigative Objectives The objectives of this study were i) to evaluate the effectiveness of twp mechanical control measures in decreasing runoff volume and sediment yield from coversoil erosion and the effect of these mechanical measures on plant growth, ii) to determine the effectiveness of biological measures in enhancing plant growth and thereby decreasing runoff volume and sediment yield from coversoil erosion, and iii) to determine the effect of coversoil depth (0 cm and 30 cm) oh plant growth, and to evaluate how coversoil affects runoff volume and sediment yield. 3 2. LITERATURE REVIEW Erosion Control Regulations Soil erosion control continues to be a significant challenge to agriculture as well as industry resulting in poor water quality due to sediment (Renard & Ferreria, 1993), geomorphological downstream impacts such as channel change (Knighton, 1998), loss of soil resources. (Toy & Foster, 1998) and transport of adsorbed chemicals (Renard Sc Ferreria, 1993). Because of this, there has been increasing demand by regulatory authorities on industry to provide erosion analyses as a part of their land management plans. Since the 1970's, the United States and the State of Montana have passed legislation that places more stringent environmental fcontrols on mining and mineral extraction operations. For example, erosion control measures have been specifically targeted under the U.S. Surface Mining Control and Reclamation Act and the Clean Water Act (U.S. Congress, 1977; U.S. Congress, 1972). Montana environmental laws place strict erosion control measures op the mining industry as well. Table I provides examples of legislation concerning soil erosion on coal and metal mines in Montana. Revised Universal Soil Loss Equation IRUSLEt The main processes influencing soil erosion by water are raindrop irtipact arid subsequent transport of soil by flowing water. Accelerated erosion is considered to be occurring when soil erosion rates exceed 0.2-0.5 Mg/ha (0.1-0.2 tons/ac) annually, which 4 Table I. Examples of Montana legislation mandating erosion control. M on tan a M in in g L aw C itation In tent Strip & Underground Mine Siting Act 82-4-202 MCA* Requires approved reclamation plan that includes erosion control measures before permit will be issued. Strip & Underground Mine Siting Act 82-4-231 MCA Mining operation must take all measures to prevent damages to the people and property by soil erosion. Strip & Underground Mine Siting Act 82-4-231 (10) (c) MCA The mine operation must impound, drain, or treat all runoff or underground mine waters so as to reduce soil erosion. Strip & Underground Mine Siting Act 82-4-231 (11) MCA All stockpiled materials resulting from land disturbances must be within permit boundaries and cannot erode off-site. Strip & Underground Mine Siting Act 82-4-233 MCA The vegetative cover must be capable of preventing soil erosion to the extent achieved prior to the operation. Metal Mine Reclamation Act 82-4-336 MCA Reclamation plan must provide that reclamation activities, particularly those relating to control of erosion, to the extent feasible, must be conducted simultaneously with the operation. Metal Mine Reclamation Act 82-4-434 (2) (g&l) MCA The department may not approve a reclamation plan or a plan of operations unless the plans provide that: ■ all access, haul, and other support roads will be located, constructed, and maintained in such a manner as to control and minimize channeling and other erosion; ■ seeding and planting will be done in a manner to achieve a permanent vegetative cover that is suitable for the postmine land use and that retards erosion. *MCA = Montana Code Annotated 5 is the rate at which soil lost to wind and water is replenished by weathering of parent material on undisturbed lands, i.e., geological erosion (Brady & Weil, 1996). Erosion is a two-fold process in which the soil particles are detached and then forces cause rolling, dragging and splashing of the particles and induce transport by water (Brady & Weil, 1996). Detachment is initiated by such processes as freezing and thawing, overland water flow, and raindrop splash applying shear stress upon soil particles. Raindrop splash and flowing water transport the loosened soil particles (Brady & Weil, 1996; Knighton, 1998). The Revised Universal Soil Loss Equation (RUSLE) equation includes fiye factofs; the erosivity potential of rainfall and runoff soil erodibility, hillslope length and slope, plant cover and management, and erosion control support practices (Toy & Foster, 1998). This factorial approach to estimating annual average soil loss is the result of a set of empirically-derived mathematical equations that have evolved from almost a century of intense erosion research in the United States. Up until the 1950's, soil and earth scientists were estimating soil loss based on equations that were formulated in very specific geologic and climatic areas and were therefore limited in their range of applicability (Renard et al., 1997). Thp United States Department of Agriculture, Agricultural Research Service (USDA, ARS) formed the National Runoff and Soil-Loss Data Center in 1954, The purpose df the Center was to collect and assimilate soil loss data. Data used to develop the USLE and RUSLE consisted of erosion-plot research collected from natural rainfall events and simulated rainfall in which water was applied to erosion plots (Toy & Foster, 1998), The erosion 6 plots were 72.6 foot long by either 6.0 or 12.0 foot wide (0.01 or 0.02 acres). The mathematical relationships betweeh each factor and soil loss were determined by regression analysis, th is analysis led to the formulation of the Universal Soil Loss Equation (USLE): A - R o K o LS o C o P Where: A= R= K= LS = C= P= Average annual soil loss in tons/acre/year Rainfall/runoff erosivity Soil credibility Hillslope length and steepness Cover-management Support practices (Toy & Foster, 1998; Renard et al., 1997) This equation should have universal validity because none of its factors utilized a reference point that has direct geographic orientation (Toy & Foster, 1998). The Revised Universal Soil Loss Equation uses.the same formula, but with updated and improved calculations for the contributing factors (Renard et al., 1997). Although there are many other models such as WEPP, ANSWERS, AGNPS, EPIC that predict erosion, RUSLE is the most widely used prediction tool to date because of ease of use, availability of parameter data, acceptable accuracy, and readily acceptable assistance from USDA Natural Resources and Conservation Service (NRCS) personnel (Renard & Ferreira, 1993; Toy & Foster, 1998; Renard et al., 1997; Yoder & Town, 1995). It is also the only water erosion prediction model adopted by all states in the United States for predicting sheet and rill erosion (USDA NRCS, 2000). 7 R - Rainfall/Runoff Erosivitv The R factor in RUSLE represents the rainfall/runoff erosivity and reflects the climatic contribution of precipitation to soil loss. The rainfall factor reflects the relationship between total storm kinetic energy (E) times the maximum 30-minute intensity (I30) (Toy & Foster, 1998). Volume of rainfall and runoff specify the storm energy (E). Prolonged peak rates of detachment and runoff are accounted for in the (I30) component. Total energy and peak intensity are combined in each particular storm to produce the statistical interaction product term El, which is an abbreviation for energy times intensity. Technically, the term indicates how particle detachment is combined with transport capacity (Renard et al., 1997). R is equal to the average annual sum OfEI30 for storm events during a rainfall record of at least 22 years (Toy & Foster, 1998). When erosion is dominated by spring thawing and snowmelt, an equivalent R value (Req) that accounts for these processes is used (Toy & Foster, 1998;'Renard et al.', 1997). K- Soil Erodibilitv The soil credibility factor is a numerical value representing the average, long-term susceptibility of soil and soil profile to a large number of erosive and hydrologic processes (Renard et al., 1997). The K factor lumps the soil and soil profile reaction to thebe processes into an integrated average annual value (Renard et al., 1997). The RUSLE software can vary K values seasonally to account for temporal variability in the processes (Renard & Ferreira, 1993). These processes consist of soil detachment and transport by raindrop impact and surface flow, localized deposition due to topography and tillage induced roughness, and rainwater infiltration into the soil profile (Renard et 8 al., 1997). If the soil is Undisturbed, K values can be obtained from published NRCS Soil Survey data. Otherwise, RUSLE software will calculate an estimated K using a soilerodibility nomograph. This nomograph combines a series of equations that estimate K based on texture (percent sand, silt, and clay), percent organic matter, soil structure, soil permeability class and percent coarse fragments. Although RUSLE K factor was specifically developed for soil properties equivalent to tilled agricultural soils, it is appropriate on reclaimed soils because the handling and management of soil material on disturbed sites often results in equivalent soil properties (Renard et ah, 1997). v LS - Hillslope Length and Gradient The LS factor in RUSLE is a combined parameter integrating length and gradient of a hill. Soil loss increases as both slope or length increases because runoff accumulates and accelerates downhill (Renard et al., 1997). The erosive force and velocity of water increases with increasing slope (Toy & Foster, 1998). The ratio of rill (concentrated) to interrill (diffuse) erosion on the hillslope is used to determine the effect of hillslqpe length on soil loss, and is high for silty and recently disturbed soils and low for clayey and sandy soils. It is a function of soil texture and general land use (Toy & Foster, 1998). The hillslope length factor L has a value of I for a "unit plot" which is defined as 72.6 feet in length with a gradient of 9 perbent (Renard et al., 1997). The L value is less than I for hillslope lengths less than 72.6 feet and greater than I foi; lengths greater than 72.6 feet. If soil loss results from interrill erosion, which is assumed to be uniform along a hillslope, the L value will be I for all lengths. If rill erosion is the main process, the L 9 factor will increase linearly with length because rill erosion increases in the downslope direction as runoff accumulates (Toy & Foster, 1998). The hillslope gradient factor, S, reflects the effect of hillslope-profile gradient on soil loss. For a unit plot, with a 9% gradient, the S value is equal to I. The S values vaiy from above to below I, depending on whether the gradient is greater than or less than that of the unit plot. Soil loss increases more rapidly as gradient increases than as length increases. Also, rill erosion is affected more by hillslope gradient than is interrill erosion (Toy & Foster, 1998). Withip RUSLEi the hillslope length (L) and gradient (S) terms are combined into a single topographic factor (LS) representing the ratio of soil loss from a given hillslope length and gradient to soil loss from the unit plot (72.6 feet in length, 9% gradieht). Thus, LS values are not absolute values but are based upon a value of I for unit plot conditions. Because land use has a large impact on rill erosion, it is as important to select the proper RUSLE land use categoiy as it is in determining hillslope length and gradient. The RUSLE software will calculate the LS factor based upon assumptions that the rill to interrill ratio is low, moderate or high for a given land use selected. C - Cover-Management The cover-management factor (C) represents the effects of vegetation and management on soil loss. As with other RUSLfe factors, the C value is a ratio comparing the existing surface conditions at a site to the standard conditions of the unit plot. The C factor represehts the effect of plants, soil covers, foots, incorporated residue, and soil-disturbing activities on soil loss. RUSLE offers a time-variant or time- 10 invariant option. The time-variant option is tp model situations where changes in soil and vegetation are anticipated to greatly affect erosion. The time-invariant scenario is used to estimate erosion on a stable landscape. Fouf subfactors are normally used to estimate the C value: prior land use, canopy cover, surface cover and surface roughness. In the Northwest Wheat and Range Region of the United States, an additional subfactor representing antecedent moisture is added. The C-factor is one of the most important factors in the RUSLE equation because it represents surface soil conditions that can be manipulated by land managers to prevent erosion, and tjie numerical C value calculated based on the above sub-factors can range from almost Oto a little more than one, thus having a large Weighted value on the total estimated annual soil loss (Toy et al., 1999). P - Support Practices The support practice factor (P) represents erosion control practices such as contouring and terracing that reduce erosion (Renard et al., 1997). The P sub-factors that are multiplied together to estimate an overall P value are based upon whether a timevariant or time-invariant option was selected when computing the C value. Ifa timeinvariant scenario is being modeled, the sub-factors used to calculate P are contouring and other mechanical disturbances. If the time-variant option is chosen, P is calculated based on contouring, permanent barrier strips, concave hillslope shapes, terracing and/or sediment basins and subsurface drainage. The RUSLE model is able to assess the effectiveness of the various support practices by weighing their effectiveness against 11 information listed in other factors. For example, contours are less effective where rainfall/runoff erosivity is high (Toy & Foster, 1998). The sediment-delivery ratio is associated with the terracing subfactor (Renard et al., 1997 and Toy & Foster, 1998). When sediment productidn in the inter-terrace interval exceeds the transport capacity of the flow in the terrace channel, deposition occurs and the sediment-delivery ratio is less than I . When the transport capacity equals or exceeds the soil loss, the sediment-delivery ratio equals I, indicating that all of the sediment is removed from the hillslope by the channel flow. The soil loss estimated by RUSLE can be multiplied by the sediment-delivery ratio to estimate the amount of sediment leaving the hillslope. The same principles are used to estimate the sedimentdelivery ratio for concave hillslope profiles. If sediment ponds or basins are used to retain sediment on-site, then the soil loss from hillslopes can be multiplied by the sediment-delivery ratio to estimate the sediment discharged into a sediment pond (Toy et al., 1999). Improved Accuracy Representing Effect of Slone Steepness RUSLE experts consider the slope steepness factor, S, to be moderately accurate for slopes over 20%. In a study done by Nearing (1997), the RUSLE functions used for the effect of slope steepness on soil logs by water were linear functions of the sine of the slope anglfe. Two linear functions are used in RUSLE: one for slopes <9% and another for >9%. By using the original data used to calculate the current linear functions used by RUSLE along with what was considered to be the best data for steeper slopes, a single, 12 continuous logistic function.was derived that he contends is equivalent to the current functions in RUSLE for slopes <25% and is better for slopes >25% (Nearing, 1997). RUSLE and Oeomomholoev Toy and Osterkamp (1995) investigated the applicability of RUSLE to geomorphological studies because of anticipated use of the model for these purposes despite the fact that analysis at geomorphic scales are outside of the model's intended scope. They indicate that soil loss estimates may be extended into the past as long as the envirohmental conditions remain virtually the same as those used in the computations. Soil loss estimates are likely to be of satisfactory accuracy at spatial scales ranging from landscape (hillslope) profiles to small drainage basins where channel processes of aggradation and degradation are insignificant (Toy & Osterkamp, 1995). Database Sensitivity of RUSLE Renard and Ferreira (1993) performed a sensitivity analysis of the three databases used in the RUSLE modeling software. They compared the percent change in a parameter to the resulting percent change in predicted soil loss. In their examination of the CITY database, which represents geographic location and associated climate, the RUSLE model was very sensitive to changes in the city codes. The CITY database contains the rainfall/runoff (R) values for locations throughout the United States. Temperature values were found to be significantly more important in estimating annual soil loss values than precipitation. This was attributed to the effect of temperature on residue decomposition. The authors stress that sensitivity will vary geographically and 13 the RUSLE may react in unpredictable ways. Sensitivity analysis should be performed based on local modeling situations, and can be a very helpful tool when allocating resources for field data collection (Renard & Ferreira, 1993). Use of RUSLE on High Elevation. Steep Slones Kapolka and Dollhopf (2001) calculated a rill formation factor using nonlinear variable estimation (Kapolka & Dollhopf2001). An adjusted soil credibility factor (Kl) is calculated by multiplying the RUSLE estimated K value by a rill formation factor (F Factor) to obtain an optimized soil credibility factor, K l. The F Factor is; 1.0 if slopes have stable to slight rilling, 8.4 for slight to moderate rilling, and 16.6 for moderate to critical rill severity. Kl is then multiplied by the other RUSLE generated factors on a spreadsheet to obtain the optimized sediment yield value. Opportunities for research include calibrating the RUSLE model for use on reclaimed lands, testing the model against applications for which it was not designed (such as mine spoil piles), investigating process-based relationships between the factors as opposed to the empirically-basfed relationships used now and creating methods that standardize the measurement of variables. Additional areas that would assist disturbed land reclamation efforts are furthdr testing of erosion control measures for input into the P factor. RUSLE is the most widely used model for estimating average annual soil loss because of its accuracy and flexibility (Yoder & Lown, 1995). In Montana, many m in in g companies and environmental consulting firms are using RUSLE version 1.06 software to estimate potential erosion resulting from mining activities. RUSLE and other erosion 14 models are being used in a variety of settings by state and federal regulatory authorities as well. The estimated annual soil loss estimated by the RUSLE model may be a part of the information used for approving final reclamation plans, pre-and post-mining permits, and reclamation bond release. Use of models requires expertise and a full dnderstanding of inputs, outputs, and a sound background when science-based estimates are required using variable data is needed or applying RUSLE to a new setting. It is important for both industry and the regulatory authorities to understand the intricacies and limitations of the erosion models. Commercial Mycorrhizal Fungi Inoculations in Mineland Reclamation Mycorrhizae are a plant-fungal symbiosis found in possibly 95 % of the world’s plants (Smith & Read, 1999). The mycorrhizae fungus receives carbon from the plant and in return enhances plant uptake of nutrients, particularly phosphorus and trace minerals (Smith & Read, 1999). Factors related to mining practices that decrease or eliminate a viable population of mycorrhizal fungi are i) removal of vegetation; ii) topsoil storage; arid, iii) disturbance of the soil (Jasper et al., 1987; Miller & Jastrow, 1992). Topsoil stockpiling can reduce the density of mycorrhizal fungi in the soil (Rives et al., 1980; Gould & Liberia, 1981; Liberia, 1981, Abdul-Kareem & McRae, 1984), depending on length of time soil is stockpiled and soil moisture content. This reduction in mycorrhizal fungi can be detrimental to not only the grass, forb, and shrub seedling establishment (Visser et al„ 15 1984; Stark & Redente, 1987; Jasper et al., 1989), but also plant community function ^specially in nutrient or moisture limited environments (Miller & Jastrow, 1992). Potential benefits of revegetation enhancement by the use of mycorrhizal inoculants include the reduction of sediment pollution of surface waters, inasmuch as surface mines are major non-point source contributors because of erosion due to plant and soil removal. In soils containing non-ferrous metal contamination^, studies have shown that mycorrhizal fungi inoculations can increase plant tolerance to heavy metals and improve plant diversity (Shetty et al., 1995; Vangronsveld et al., 1996; Lambert et al., 1979). Mycorrhizal fungi also make an important contribution to restoring lost soil structure by the formation and stabilization of soil macroaggregates, which have an influence on soil quality and erosion, mobility of hazardous chemicals and remediation of contaminated sites (Jastrow et al., 1998). 16 3. METHODOLOGY Site Description The Treasure Mine open pit talc mine is located in southwestern Montana approximately 24 kilometers northeast of Dillon, Montana, in the Ruby Mountain Range (Figure I). Native vegetation is sagebrush grassland on south facing slopes and lodgepole pine/Douglas fir on slopes facing north. Elevation is approximately 2590 meters. Average annual precipitation, based on 20 years of record, is 26.0 cm. Average yearly maximum temperature is 14.8° C, minimum temperature is -1.3° C with 95 freeze-free days per year (Western Regional Climate Center, 2001). Glendive .Missoula Helena Billin1 Dillort ^ Miles City ■Ennis Treasure Mine Figure I. Location of study site in southwest Montana. 17 Experimental Design The experiment was constructed on a regraded slope having a uniform slope gradient of 25 %. The five following biological, mechanical, and soil depth treatments were tested: i) Control: Spoil backfill material graded to 25 % slope gradient. ii) Coversoil: 30 cm thick coversoil application placed over spoil backfill material graded to a 25 % slope gradient, iii) CoversoiIZPitting: 30 cm thick coversoil application placed over spoil backfill material graded to a 25 % slope gradient, with pitting. Pit dimensions were approximately 900 cm3 and dug by hand. Pits were staggered in a checkerboard pattern with alternating rows of two and three pits. Distance between pits was 3.39 m. iv) Coversoil/Slash Barriers: 30 cm thick coversoil application placed over spoil backfill material graded to a 25 % slope gradient, with four slash barriers (3.1 m wide by 0.8 m long) installed every 6.8 m along the slope. The slash barriers were constructed with lodgepole pine branches measuring 8 cm or less diameter cut fresh from nearby trees and anchored tp the soil surface with wire and stakes. Fine branches and needles were allowed to remain on the branches. Branches were staked flush to the soil surface to prevent undercutting of the barriers by water. v) 30 cm coversoil application placed over spoil backfill material graded to 25 % 18 slope gradient, with commercial mycorrhizal fungi inoculation. Pelletized AM inoculum provided by PHC Reclamation, Inc., was applied at 37.0 liters per hectare. Each treatment was replicated three times in a completely random experimental design for a total of fifteen test plots (Figure 2). Each plot was 3.1 meters wide and 30.5 meters long and was bounded laterally by a silt fence to prevent sediment and runoff from flowing onto adjacent plots. A diversion ditch was constructed above the test plots to prevent upslope runoff from entering the plots. Troughs were installed at the base of each plot to collect runoff and sediment. Sediment Collection Trough Design Sediment and runoff from eroding experimental plots was captured by a collection trough, recessed into the ground so that the upper lip of the trough was level with ground surface. Each trough was 3.1m long by 1.2 m wide by 0.6 m deep. Trough capacity was designed to capture approximately 25 % of the runoff from a 24 hour - 100 year precipitation event, assuming no infiltration. The transitions between treatment plots and collection troughs were packed with bentonite clay to-minimize, undercutting between slope and trough. SeedMix and Seeding Procedures Test plots were seeded by a Barretts Minerals contractor on June 24,2000. Seed was broadcast by hand and raked into the surface. Table 2 presents the seed mix and 19 Individual Plot Description (not to scale). All plots have a 25 % slope. Plots were 3.1m wide and 30.5 m long (10 ft x 100 ft). Sediment and water moving off plots were captured in a collection trough buried in the ground at the toe of the slope. Silt fences were installed on the top and sides of the plots. Upslope Silt fence 3.1 m 30.5 m Downslope Collection trough buried beneath ground surface Completely Random Experimental Design (not to scale). The fifteen test plots drawn below represent the five treatments (A - E), each replicated three times. Treatment Kev: A = 30 cm Coversoil B = 30 cm Coversoil/AM Inoculum C = 30 cm Coversoil/Slash Barriers D = 30 cm Coversoil/Pitting E = No Coversoil Runon diversion ditch P \ B \ E \C \ E \ A \ I ^ B \ C \ D \ A \C \ A \ E \ B Collection troughs Figure 2. Design and layout of test plots at the Treasure Mine, MT. 20 Table 2. Seed mix and application rate on test plots. Species C om m on nam e A g r o p y r o n d a systa ch yu m A g ro p y ro n sp ica tu m Thickspike wheatgrass Bluebunch wheatgrass Slender wheatgrass Sheep fescue Canada bluegrass White yarrow Alfalfa Sanfoin Barley A g ro p y ro n trach ycau lu m F e stu c a o vin a P o a c o m p re ssa A c h ille a m illefoliu m M e d ic a g o s a tiv a O n o b ryc h is v ic ia e fo lia H o rd eu m vu lg a re application rates. An annual barley species, H o rd eu m P lant type Pure L ive Seed (PL S) (kg/ha) Grass Grass Grass Grass Grass Forb Forb Forb Grass Total vu lg a re, 10.5 11.6 9.9 2.7 2.9 0.6 2.9 8.5 24.2 73.9 was included with the perennial seed mix to provide rapid cover. All plots were broadcast fertilized with 36kg/ha nitrogen and 36-kg/ha phosphorus after the test plots had been constructed. Commercial AM Inoculum Application Procedures The AM inoculum was the pelletized form and applied at 37.0 liters per hectare. The commercial AM inoculum was provided by PHC Reclamation, Inc. Treatment plots were inoculated by broadcasting the inoculum onto 6 m long x 3 m wide subsections and then covering the pellets with 5 cm of coversoil. One hundred milliliters of AM inoculum was applied to each subsection, for a total of 500 mL of AM inoculum per treatment plot. 21 Data Collection and Analysis Spoil Backfill and Coversoil Phvsiochemical Analysis Soil physiochemical characteristics were determined by collecting composite samples of the spoil backfill test plots (Control treatment) and plots with coversoil (Coversoil, Coversoil/Pitting, Coversoil/Slash Barriers, Coversoil/AM Inoculum treatments). Composite soil samples were oven dried at 41° C and disaggregated using a mortar and pestle. Analytical procedures used are reported in Table 3. Precipitation and Evaporation Measurements An on-site precipitation-recording gage located next to experimental plots monitored precipitation. A solar powered Campbell Scientific CR-IO datalogger recorded precipitation data on an hourly basis and in one-millimeter increments. Hourly measurements gave an indication of the intensity of various precipitation events. Precipitation data are reported in Appendix B, Tables 27 - 38. A Class I evaporation pan was installed adjacent to the precipitation gage to measure evaporation at the site. A 200-liter capacity stilling well was connected to the Table 3. Soil physiochemical analytical methods. V ariab le A nalytical T ech n iq u e Particle size distribution Day 1965. Hydrometer method. Coarse fragment percentage Sieved 2 mm fraction, measured weight and volume. Electrical conductivity, pH, and Rhoades 1982. Water saturated paste extract. sodium absorption ratio Organic matter percentage Nelson and Sommers 1982. Walkley-Black method. 22 evaporation pan by a hose and a constant water level in the evaporation pan was maintained using a float and valve check. The volume of water evaporated each hour was recorded using a Stevens recorder located in the stilling well and used to calculate evaporation (cm). Evaporation data are reported in Appendix B, Table 39. Runoff Collection Methods Rundff accumulated in collection troughs was measured every two weeks from late spring through early fall. Depth of water in the troughs was measured to the nearest millimeter. To convert depth of water to runoff volume in liters, Equations 1-3 in Figure 3 were used to calculate the area of the cross section of wafer from the known variables of trough diameter and water depth. Runoff data are reported in Appendix C, Tables 4243. Precipitation falling into the trough and evaporation of water from the trough were accounted for using data collected from the precipitation gage and the evaporation pan (Appendix B, Tables 27-39). Total maximum amount of runoff was calculated using Equation 4. Total Runoff = (Initial Water in Trough) - (Precipitation) + (Evaporation) Equation 4 Sediment Collection Methods Accumulated sediment in collection troughs was measured and collected every two weeks from late spring to early fall during 2000 and 2001. After water depth was measured, a submersible pump powered by a gasoline generator was used tp remove the 23 Calculation for area of a segment of circle (the area of the trough occupied by water) of depth y. 'd _ 6 2 cos 1 2 d < 2 Equation I y y4(m2) = — (<9-sin 6>) 8 Equation 2 where: d = trough diameter (m) y = water depth in trough (m) A = area of water in trough (m2) Multiply by trough length to obtain volume: Volume (m3) = Area x length Equation 3 Figure 3. Calculation to convert water depth in trough into volumetric measure. 24 water from the troughs. Sediment was collected in 19-liter buckets using spades and shovels. Samples less than 22 kilograms were transported back to Montana State University, oven-dried at 41° C and weighed. If there was greater than 22 kilograms of sediment in the trough, the total volume of sediment was measured and the mass of dry soil was determined using known mass values for a given volume of saturated sediment. Sediment yields are reported in Appendix C, Tables 40-41. Rill Classification Methods Rill severity on experimental plots was classified during every monitoring cycle of the study period using the Erosion Condition Classification, Montana Revised Method (Clark, 1980). Depth, width, and frequency of rills are the criteria used to diagnose severity (Table 4). Rill classification data for test plots are reported in Appendix C, Tables 44-45. Table 4. Soil erosion condition classification for rills. Q u alitative R an k in g D escription R ank Stable Rills, if present, are less than 0.5 inch deep, and generally at infrequent intervals over 10 feet. 0 or I Slight Rills are mostly 0.5 to I inch deep, and generally at infrequent intervals over 10 feet. 2 Moderate Rills are mostly I to 1.5 inches deep, and generally at 10 feet intervals. 3 Critical Rills are mostly 1.5 to 3 inches deep, and at intervals of 5 to 10 feet. 4 Severe Rills are mostly 3 to 6 inches deep, and at intervals of less than 5 feet. 5 25 Plant Measurements . During 2001, plant canopy cover, basal cover and aboveground plant biomass (biomass) were measured during the peak of the growing season. All three variables were analyzed by growth form (i.e., annual or perennial grasses, forbs). Plant growth measurements are reported in Appendix D, Tables 46 ^ 57. Transect locations were staked on all plots. These transects were along the diagonal, running from the upper left-hand comer to the lower right hand comer of each plot. Ten quadrats were sampled on each test plot to measure plant cover and biomass. Quadrats were placed every 3 m beginning at the 3 m point along the transect. Canopy and basal cover were estimated using a 20 x 50 centimeter Daubehmire frame. Cover whs estimated by growth form, i.e., perennial grass, annual grass, or forb. These cover values were averaged across quadrats to determine plant canopy and basal cover. Rock fragments, litter, and bare ground were also measured in terms of cover. All cover measurements were classified using a scale of 0 - 10 where 0 = no cover, 1 = 1 10 % cover, 2 = 11 —20 % cover and so. forth. Biomass was measured using a 20x20 centimeter frame on the same quadrants used to measure cover. Vegetation within the frame was clipped two centimeters above the ground, sorted by growth form, and placed into paper bags. These samples were oven-dried at 49° C to a constant weight. Vegetation was weighed and biomass for each life form was calculated on a kg/ha basis. 26 Pre-Inoculation AM Colonization Levels of Goversoil and Spoil Rack-fill Material A greenhouse study was conducted to determine whether propagules of mycorrhizal fungi were present in the coversoil and spoil backfill material prior to application of the commercial AM inoculum. Bulk composite samples were collected of the coversoil and spoil backfill material with a hand trowel every 3 meters along the slope. Hand trowels were thoroughly cleaned, rinsed and dried between plots. Each bulk composite sample consisted of 10 scoops from each treatment replication. Soils were brought to the Montana State University Plant Growth Cfenter and planted with Sorghum Sudanese (Sudan grass). Fifty seeds per pot were planted 2 cm deep and kept moist with a water mister until plants emerged. After germination, plants were culled to five per pot, and allowed to grow for 90 days, with a 14-hour photoperiod, a daytime temperature of 2 10C and a nighttime temperature of 18 0C. Roots were harvested and analyzed for presence o f-a n d percent colonization of - AM fungi (Appendix D, Table 58). Percent Colonization by AM Fungi Procedures Percent of root length colonized by AM fungi was determined after clearing and staining root samples. Roots that had been washed free of soil were cut into 2 cm segments, cleared with 1 5 % KOH solution for 48 hours, soaked in HCl for 12 hours and stained with 0.05 % trypan blue stain in lactoglycerol. Two slides with twelve root segments per slide were made for every plant sample. Transects recording presence or absence of mycorrhizal structures were conducted across the roots. Ninety-six observations of root segments per plant were observed with 200-x magnification. The 27 presence of AM hyphae, vesicles, arbuscules, or non-AM hyphae was recorded for each intersection. Total colonization was calculated using Equation 5. % AM Colonization (intersections with hyphae, vesicles, or arbuscules) (total intersections) Equation 5 Mvcorrhizal Infection Study Vegetation and the AM colonization levels were sampled during the second year of plant growth (August, 2001). Four plants o f Agropyron trachycaulum and Hordeum vulgare were collected to a 30 cm depth from the Coversoil, Coversoil/AM Inoculum and Control treatment plots. Plants were transported in cold-storage to Montana State University laboratory facilities for analysis. Roots were examined to determine if mycorrhizal fungi were present. Percent AM colonization o f A. trachycaulum and H. vulgare are reported in Appendix D, Tables 59-60. Statistical Analysis Analysis of variance techniques and mean separation tests were used to ascertain whether significant differences were present at the 95 % level of confidence (P = 0.05). Significant differences at P < 0.05 were separated using the Student-Newman-Keuls method of pairwise multiple comparison for equal size data sets. Least-squares regression was used to evaluate associations between independeht and dependent variables. Multivariate associations were tested using multiple linear regression analysis. These analyses were made using SigmaStat version 2.0 software (Jandel 1995). 28 RUSLE v.1.06 Computer Model Analysis RUSLE version 1.06 is a DOS computer model (Galetovic, 1998). Various input variables were required for each factor in the RUSLE model (Table 5). Using mathematical equations, RUSLE estimated an average annual sediment yield. Input values were either from field data, from Renard et al. (1997), or were provided by the United States Department of Agriculture Natural Resource Conservation Service State Agronomist (Fasching, 2000). Table 5. Input variables for RUSLE version 1.06. R U S L E F actor In p u t V ariab le R - Rainfall/Runoff Erosivity Factor City climate database* D ata Source Renard et al. (1997), Field Initial R value Field K - Soil Erodibility Rock cover % Field Number of years to consolidate Renard et al. (1997) Hydrologic group Renard et al. (1997) Surface texture (% clay, % silt) Field Organic matter % Field Soil permeability class Renard et al. (1997) Coarse fragment % Field LS - Slope length and Number of hill segments Field Gradient General land use Field Slope gradient Field Slope length Field C - Cover Management Effective root mass Fasching (2000) Canopy cover % Field Fall height of precipitation Field Roughness of field condition Field Ground cover % Field Rock cover % Field *City climate database included the following values: storm energy and intensity (EI) curve value, 10 year EI value, an initial R value, number of freeze-free days per year, site elevation, mean monthly temperature, and mean monthly precipitation. All data, except for elevation and monthly precipitation, were obtained from Renard et al. (1987). Elevation and monthly precipitation data were collected in the field. 29 Hillslope Area Calculations Rill severity class and hillslope area were used as multiple linear regression (MLR) independent variables to predict Year 2000 sediment yields and runoff volumes. Plant growth was negligible during 2000 and thus plant growth effects were omitted from the regression model. In Year 2001, rill severity class, hillslope area, plant biomass, and percent plant cover were used as the MLR independent variables of sediment yields and runoff volumes. The Coversoil/Slash Barrier and Coversoil/Pitting treatments provided barriers to movement of water and sediment downslope into the collection trough, so the surface area of these experimental plots contributing to sediment yield and runoff were smaller than the Coversoil, Coversoil/AM inoculum and Control treatments. Because of this, the hillslope area variable was added to the MLR model. The total area of the Coversoil/Slash Barrier plots contributing to sediment yield and runoff was Palculated using height as the distance from the bottom of the lowest barrier on the test plot down to top of the collection trough multiplied by the plot width (6.8 m x3.1 m = 21.0 m2). Area of Coversoil/Pitting treatment plots contributing to sediment yield was the total area of the test plot between the bottom of the plot up to the nearest pit (Figure 4). Total area of the pitted plots contributing to sediment yields was 18.9 square meters. The area of the Coversoil, Coversoil/AM inoculum and Control plots were 94.55 square meters, or the area of the entire plot. 30 ▲ O O O O O O O O Total plot length = 30.5 m O a O O O O O O O O P O Q_ A 6.77 m a a 3.39 m v r ◄-------- ► 0.62 m < —--------------------------------Total plot width = 3.1 m Figure 4. ► Schematic of dimensions used to calculate area contributing to runoff and sediment yield on pitted treatment plots. Drawing not to scale. 31 4. RESULTS AND DISCUSSION Coversoil and Spoil Backfill Phvsiochemical Characteristics Coversoil applied to experimental plots was taken from a nearby stockpile of native coversoil recovered during mining operations at the Treasure Mine. Coversoil texture was sandy loam (Table 6). Chemical characteristics of the coversoil were all within ranges that are not limiting to plant growth (pH = 6.8, electrical conductivity (EC) = 0.9 mmhos/cm, sodium absorption ratio (SAR) = 0.1). Coversoil characteristics that could impair vegetation establishment and growth were the high coarse fragment percentage (49 % by weight and 38 % by volume) and low percentage (0.6) of organic matter. The spoil backfill texture was sandy loam. Coarse fragment percentage was 64 % Table 6. Coversoil and spoil backfill physiochemical characteristics. Soil P roperty C oversoil Spoil B ack fill Sand percentage^ Silt percentage* Clay percentage* Textural class* Coarse fragment percentage (weight)* Coarse fragment percentage (volume)* pH# EC (mmhos/cm/ SAR* Organic matter percentage* * n=l + n=2 # n=3 1 mean ± I standard deviation 65.4 ± 0.0V 19.0+ O-Ov 16.6 ± 0.0v sandy loam 49 38 6.8 ± 0.05 v 0.9 ± 0.02v 0.1 0.6 63.5 ± 0.0 15.7 ±0.0 20.8 ± 0.0 sandy loam 64 51 7.4 ± 0.03 1.2 ±0.01 0.8 0.1 32 by weight and 51 % by volume, and organic matter was 0.1 %. Chemical characteristics of the spoil backfill (pH = 7.4, EC= 1.4 mmhos/cm, SAR = 0.8) were suitable for plant growth. Sediment Yields on High Altitude Steep Slopes Total annual sediment yield during 2000 was low (mean = 0.11 Mg/ha, n = 15), and increased during the second year (mean = 1.17 Mg/ha, n = 15). Figure 5 is a comparison of mean annual sediment yield by treatment for the study period. The low ■Year 2000 □Year 2001 -s2 .y > S E •g CA 23 I §<L> Coversoil Coversoil/Pitting Coversoi 1/Slash Barriers Coversoil/AM Inoculum * Control Mean of three replications. Bars are one standard deviation Figure 5. Comparison of mean annual sediment yields by treatment during 2000 and 2001. 33 sediment yield for the first year was a result of infrequent, low-intensity precipitation. Total precipitation in 2000 was 24 % below normal annual rainfall at the Dillon WMCE, Montana recording gage. Sedimeht yield increased during the second year although total rainfall amounts in 2001 were 36 % below normal average annual rainfall at the Dillon WMCE, Montana recording gage. Greater sediment yield the second year was the result of two strong Summer storm events during July and August, 2001. These two precipitation events generated more sediment yield than any other events during the twoyear study period. Due to below normal precipitation, vegetative growth was negligible during the fust year of the study and developed to an average of 15 % plant canopy cover in 2001. Although the soil surface was largely bare of vegetation during the first year, sediment yield was higher during the second year of study due to more erosive precipitation. The vegetative cover during the second year of the study was still not well developed. Effect of Mechanical and Biological Erosion Control Measures on Sediment Yield Sediment yields were significantly lower on the CoversoilZPitting treatment at the 10 % probability level of confidence during 2000 (Table 7). There were no significant differences between treatments during either year of study at the 5 % probability level. Sediment yields measured were highly variable except on pitted slopes. This variation could be attributed to rill formation that developed on some plots. Lower sediment yields measured on pitted slopes were attributed to minimization of rill formation on the soil surface. Rill formation provided a conduit for concentrated flow of water across the soil surface, increasing the velocity and erosivity of water moving downslope. 34 Table 7. Mean* sediment yield by treatment during 2000 and 200 L+ T reatm ent Y ear 2000 M ean* S ed im en t Y ield (M e/h a) Y ear 2001 Pm P..o~ a b a a a Coversoil 0.15 1.68 a Coversoil/Pitting 0.04 0.21 a Coversoil/Slash Barriers 0.09 1.01 a Coversoil/AM Inoculum 0.08 1.60 a Control 0.21 1.34 a * Mean of three replications. Means followed by the same letter in the same column are not significantly different. Test of significance is for P = 10 %. Treatment differences were not significant at P = 5 %. Effect of Rill Severity Class on Sediment Yield In 2000, mean rill severity varied from stable to slight and there were no significant differences between any of the treatments (Table 8). In the 2000 field season, sediment yield was dominated by sheet erosion and slight rilling and sediment yields were low. The Coversoil/Pitting treatment had significantly lower rill severity ratings than all other treatments during 2001. Rill severity class was strongly related to sediment yield both years (Figure 6). In Table 8. Mean* rill severity class** by treatment during 2000 and 200L+ M ean* R ill S everity T reatm ent_____________________________ Y ear 2000 Y ear 2001 Coversoil 1.7 a 3.5 a Coversoil/Pitting 1.0 a 1.5 b Coversoil/Slash Barriers 1.3 a 2.5 a Coversoil/AM Inoculum 1.3 a 2.8 a Control 1.3 a 3.2 a * Mean of three replications. ** Class: I = stable, 2 = slight, 3 —moderate, 4 —critical, 5 = severe. Means followed by the same letter in the same column are not significantly different. 35 2 Year 2000 <u (Mg/ha) P = <0.01 c U P Mean* Annual Rill Severity Class Year 2001 (Mg/ha) P = <0.01 cC < I Mean* Annual Rill Severity Class * Mean of rill severity class individual plots received at every twoweekmonitoring cycle throughout the season (n = 15). (Rill Severity Class: I=Stable, 2=slight, 3 = moderate, 4 = critical, 5 = severe) Figure 6. Strength of relationship of mean rill severity class to total annual sediment yield during 2000 and 2001. 36 2000, all test plots exhibited final rill severity classes of mostly stable or slight, which was showed a strong linear relationship with total annual sediment yield (r = 0.76). In 2001, total annual sediment yield showed a strong exponential relationship with mean rill severity class (r = 0.87). Test plots that were assigned with a rill severity class of moderate to critical showed an exponential increase in sediment yield at the point when rill severity class exceeded moderate levels. These data indicate that once rill formation occurred beyond the moderate rill severity class, sediment yields were accelerated. Effect of Precipitation on Sediment Yield Total precipitation, maximum daily, and maximum hourly precipitation and mean sediment yields measured for all plots during each two-week period are presented in Table 9. These results were obtained by calculating the mean total sediment yield collected at the end of each two-week monitoring period for comparison to on-site precipitation gage records. Table 9. Mean* sediment yield and precipitation across all treatments for two-week periods during 2000 and 2001.+ D ate S ed im en t Y ield (M g/ha) T otal P recipitation (cm ) 8/2/00 0.019 9/16/00 0.020 10/19/00 0.073 7/21/01 0.376 8/5/01 0.791 9/18/01 0.003 * Mean of fifteen replications. Only sediment yield events are reported. 0.1 0.7 2.4 3.8 0.9 3.3 M axim um D aily P recipitation (cm ) M axim um H ourly P recipitation (cm ) 0.0 0.2 2.3 0.9 0.7 2.0 0.0 0.1 1.7 0.7 0.4 0.9 37 Sediment yield increased with increasing amounts of total precipitation received during the two-week monitoring cycle in 2000 (Figure I). In 2001, sediment yield did not increase with increasing amounts of precipitation. Duration of precipitation and mean sediment yield in the year 2000 was strongly positively related to sediment yield for maximum daily and maximum hourly precipitation but not in 2001 (Table 10). In 2001, sufficient precipitation accelerated the rilling processes on test plots (Table 8). Rainfall in July of 2001 generated considerable sediment yield and rilling of the soil surface. During the two-week period ending July 21, 0.7 cm of precipitation fell on July 8, 0.9 cm on July 14, and 0.7 cm fell on July 16. Marked increases in the severity of existing rills along with the formation of new rills on plot soil surfaces were recorded when the sediment was collected on July 21,2001, yielding a mean sediment yield of 0.376 Mg/ha. Intense precipitation occurred again in the August 5 two-week monitoring cycle, which produced less total precipitation overall, but the maximum daily amount of Table 10. Strength of relationship of total precipitation, maximum daily precipitation, and maximum hourly precipitation to mean* sediment yield across all treatments for two-week periods during 2000 and 2001. In d ep en d en t V ariab le D ep en dent V ariab le Total Precipitation Sediment Yield Maximum Daily Sediment Yield Precipitation Maximum Hourly Sediment Yield Precipitation * Mean of three replications. C orrelation C oefficien t (r) P V alu e C orrelation C oefficien t (r) P V alu e Year 2000 0.97 0.17 0.99 0.04 Year 2001 -0.79 0.43 -0.91 0.19 1.00 -0.99 0.02 0.14 38 4.50 Year 2000 4.00 3.50 2.00 1.00 Total Precipitation (cm) Mean- Sedimen1 Yield(Mgdla) I---- 1Mean Sediment Yield (Mg/ha) —♦—Total Precipitation (cm) 0.50 7/19/00 - 8/2/00 9/2/00 - 9/16/00 10/4/00 - 10/19/00 • M in ™ , YieId(MgZha) I-----!Mean Sediment Yield (MgTia) —♦—Total Precipitation (cm) Year 2001 » 3.50 3.00 2.00 S 1.50 15 7/7/01 - 7/21/01 7/21/01-8/5/01 9/4/01 -9/18/01 Means are an average of 15 test plots. r^i Bars are one standard deviation. Figure 7. Comparison of total precipitation and mean sediment yield across all treatments for two-week periods during 2000 and 2001. 39 rainfall received was very similar to that measured in July (Table 9). The August rainfall event was similar in intensity to the one in July when 0.7 cm of rain fell on July 30, yielding the largest sediment yield of 0.791 Mg/ha. This larger amount of sediment from one precipitation event reflects the increased erosion of the soil surface during active rill formation. The mean sediment yield during the September 18 two-week monitoring cycle was lowest overall (0.003 Mg/ha), even though maximum daily (2.0 cm) and maximum hourly precipitation (0.9 cm) received were the highest. Precipitation received during September of 2001 generated little or no erosion indicating that the rills had stabilized and were acting mainly as conduits of water rather than sediment. Effect of Rock Cover on Sediment Yield. Plant Biomass. Runoffand Rill Severity Mean percent rock cover varied between 36 and 58 % during 2001 and the differences among treatments were not significant. Mean percent rock cover values are presented in Table 11 for each treatment type. Percent rock cover was not significantly related to sediment yield, runoff or rill severity class during 2001 (Table 12). Plant biomass was negatively related to rock cover in 2001 (r = -0.68). Table 11. Mean* percent rock cover by treatment during 2001.+ T reatm ent M ean R ock C over (% ) Coversoil 36 a Coversoil/Pitting 45 a Coversoil/Slash Barriers 40 a Coversoi 1/AM Inoculum 42 a Control 58 a * Mean of three replications. Means followed by the same letter in the same column are not significantly different. 40 Table 12. Strength of relationship of percent rock to sediment yield, biomass, runoff and rill severity class cover during 2001. In d ep en d en t V ariab le D ep en d en t V ariab le Rock Cover (%) Rock Cover (%) Rock Cover (%) Rock Cover (%) Sediment Yield (Mg/ha) Biomass (kg/ha) Runoff (m3/ha) Rill Severity Class C orrelation C oefficien t (r) P V alue 0.06 -0.68 0.41 0.23 0.85 <0.01 0.13 0.40 Results from this study indicate that the decreased rock cover in the treatments with coversoil application (36 - 42 %) were associated with better plant growth and no significant decreases in sediment yields were provided by the increased rock cover in the control during this study. Runoff on High Altitude Steep Slopes Effect of Runoff on Sediment Yield and Rill Severity Class Runoff was not significantly different between any of the treatments during 2000 and 2001 (Table 13). Figure 8 compares mean sediment yield and runoff measurements by treatment. Runoff was not related to sediment yield in either year (Table 14). Table 13. Mean* annual runoff (m3/ha) by treatment during 2000 and 2001. T reatm en t M ean* A nn u al R u n o ff Y ea r 2000 Y ear 2001 Coversoil 49.2 a 123.5 a Coversoil/Pitting 39.7 a 66.0 a Coversoil/Slash Barriers 45.3 a 119.6 a Coversoil/AM Inoculum 43.2 a 99.8 a Control 71.5 a 202.7 a * Mean of three replications. Means followed by the same letter in the same column are not significantly different. 41 250 ] Mean Sediment Yield ■Mean Runoff 2000 S 1.0 100 §<L> & / 3P Cf dp I 200 & o 150 2000 I II 15 50 * 0 S I z 250 g ] Mean Sediment Yield 2001 - Mean Runoff 2001 200 & to 150 100 § y 1.0 15 0.5 * I Z / Z Z z 0° G^ G° y # V G° * Mean of three replications. F 1H Bars are one standard deviation. Figure 8. Comparison of mean sediment yield and runoff by treatment during 2000 and 2001. 42 Table 14. Strength of relationship of runoff to sediment yield and rill severity class during 2000 and 2001. C orrelation C oefficien t (r) In d ep en d en t V ariab le D ep en d en t V ariab le 2000 Runoff (m3/ha) 2001 Runoff (m3/ha) 2000 Runoff (m3/ha) 2001 Runoff (m3/ha) 2000 Sediment Yield (Mg/ha) 2001 Sediment Yield (Mg/ha) 2000 Rill Severity Class 2001 Rill Severity Class P V alue 0.04 0.03 0.83 0.21 0.89 0.93 <0.01 0.44 Runoff was strongly related to rill severity during 2000 but not during 2001 (Table 14). A possible explanation for the lack of relationship between rill severity and runoff in 2001 is that rilling increased on all test plots during July and August. During September, precipitation amounts similar to the previous storms generated runoff from the test plots but little to no sediment yield was measured (Tables 7 and 9). Plant Growth on High Altitude. Steep Slopes Effect of Erosion Control Measures on Plant Growth Characfenstirs Mean biomass, canopy cover and basal cover were significantly higher on plots with a coversoil application during 2001 when compared to the Control (Table 15). Table 15. Mean* plant growth characteristics by treatment during 200L+ B iom ass (kg/ha) T reatm ent C anop y cover B asal cover (%) (%) Coversoil 185 a 16 a 6 a Coversoil/Pitting 129 a 15 a 4 a Coversoil/ Slash Barriers 225 a 17 a 5 a Coversoil/ AM Inoculum 130 a 15 a 4 a Control 27 b 7 b I b * Means are an average of three replications. + Means followed by the same letter in the same row are not significantly different. 43 However, there were no significant differences among treatments that received a coversoil application, indicating that the Coversoil/Pitting, Coversoil/Slash Barriers, and Coversoil/AM Inoculum treatments during the period of this study neither enhanced nor reduced plant growth when compared to the Coversoil treatment. Plant growth developed very slowly during the year 2000 due to low precipitation following seeding. Therefore, no plant measurements were made. Effect of Plant Growth on Sediment Yield, Runoff and Rill Severity Class Plant growth was not related to sediment yield, runoff, or rill severity class in 2001 (Table 16). Although there was significantly more plant growth on the plots with coversoil compared to the control in 2001, the increased biomass and plant cover did not result in significantly less measured sediment yield or runoff (Tables 7 and 13). Low precipitation during 2001 contributed to slow plant development during the second season. Canopy cover (7 - 17%) and basal cover (I - 6%) were small (Table 15) and did not have a significant effect on sediment yield and runoff during 2001. Table 16. Strength of relationship of plant growth characteristics to sediment yield, runoff and rill severity class during 2001. In d ep en d en t V ariab le D ep en d en t V ariab le Biomass (kg/ha) Canopy cover (%) Basal cover (%) Biomass (kg/ha) Canopy cover (%) Basal cover (%) Biomass (kg/ha) Canopy cover (%) Basal cover (%) Sediment Yield (Mg/ha) Sediment Yield (Mg/ha) Sediment Yield (Mg/ha) Runoff (m3/ha) Runoff (m3/ha) Runoff (m3/ha) Rill Severity Class Rill Severity Class Rill Severity Class C orrelation C oefficien t (r) P V alue -0.29 -0.01 -0.30 -0.43 -0.41 -0.37 -0.02 -0.29 -0.26 0.29 0.99 0.41 0.11 0.13 0.18 0.95 0.30 0.34 44 Pre-Inoculation Mvcorrhizal Infectivitv Potential To determine whether propagules of mycorrhizal fungi were present in the coversoil and soil backfill material prior to application of commercial AM inoculum, S orgh u m Sudanese (Sudan grass) was planted in the coversoil and spoil backfill material sampled after experimental plot construction but prior to the application of the commercial AM inoculum. Mycorrhizal fungi propagules were present in the coversoil and spoil backfill material, as evidenced by AM formation in S orgh u m roots (Table 17). Effect of AM Inoculum on Colonization Levels in A g ro v v ro n tra ch yca u lu m and H o rd eu m v u ls a r e There were no differences in percent colonization of the roots by mycorrhizal fungi in H. vu lg a re (Table 18). In A. trach ycau lu m , the AM inoculum treated plots showed significantly higher mycorrhizal colonization levels, as compared to plant roots from the coversoil and no coversoil treat plots (Table 18). However, there were no significant differences between any of the above-ground plant growth characteristics on plots that received a coversoil application (Table 15). Both plant species were colonized by AM fungi at a relatively high level, and there is probably no measurable ecological difference between 46 % and 53 % colonization rates. With such high colonization in Table 17. Mean*' percent pre-inoculation AM colonization levels in the coversoil and spoil backfill material during 2000.+ T reatm ent P ercen t A M C olon ization L evels Coversoil 39 a Spoil Backfill Material 30 a * Means are an average of nine replications. Means followed by the same letter in the same row are not significantly different. 45 Table 18. Mean* percent AM colonization levels of H ordeu m tra ch yca u lu m during 2001.+ vu lg a re and A g ro p yro n P ercen t A M C olon ization L evels Hordeum vulgare Agropvron trachycaulum Coversoil 34 a 46 a Coversoil/AM Inoculum 35 a 53 b Control 34 a 44 a * Means are an average of nine replications +Means followed by the same letter in the same column are not significantly different. both AM-treated and non-AM treated plots, we would expect to see no biomass differences between those treatments. AM inoculation in this study seems to have been unnecessary, since AM propagules were present in the coversoil and spoil prior to AM. inoculation. This AM inoculation treatment was not found to enhance either AM inoculation levels or plant growth. Ability of Measured Factors to Predict Sediment Yield and Runoff Sediment yield was significantly related to measured factors during both years of study (Table 19). Runoff was not significantly related to measured factors either year. Hillslope area was added as an independent variable to the regression model to represent pitting and slash barrier treatment effects on sediment yields Sediment yield during both years of study was highly related to maximum hourly precipitation, increase in rill severity class and runoff (r = 0.99). These factors were chosen because newly constructed slopes are most vulnerable to erosion during high intensity storms. Sediment yields during this study did not always reflect a positive 46 Table 19. Multiple linear regression analysis results using measured factors to predict sediment yield and runoff during 2000 and 2001. D ep en d en t V ariab le In d ep en d en t V ariables P V alues o f In depend en t V ariables M u ltip le C orrelation C oefficien t (r) P V alu e for R egression Sediment Yield 2000 Mean Rill Severity Class Runoff Slope Area <0.01 0.73 0.43 0.88 <0.01 Sediment Yield 2001 Mean Rill Severity Class Runoff Slope Area Biomass Canopy Cover Basal Cover Rock Cover 0.81 0.22 0.14 0.09 0.54 0.18 0.15 0.93 0.02 Runoff 2000 Mean Rill Severity Class Slope Area 0.21 0.12 0.49 0.20 Runoff 2001 Mean Rill Severity Class Biomass Canopy Cover Basal Cover Rock Cover Slope Area 0.59 0.56 0.65 0.68 0.96 0.85 0.56 0.72 Sediment Yield 2000 and 2001 Maximum Hourly Precipitation Increase in Rill Severity Class Runoff 0.99 0.02 0.01 0.05 0.01 linear relationship with precipitation (Figure 7). This is due to increases in rill formation during the summer of 2001. It is presumed that during July and August, the rills were actively moving sediment as precipitation occurred. By September, the rills seem to have stabilized and did not move appreciable amounts of sediment when compared to July and 47 August. For this reason an increase in rill severity between events would more effectively model the behavior of sediment yields during this study. A zero would mean that rill severity class on slope remained stable and increase in rill severity would reflect plots that were actively rilling and give a relative value of the magnitude. Prediction of sediment yield during this study appeared to be estimated by maximum hourly precipitation, runoff and rilling activity on the plots Ability of RUSLE to Predict Sediment Yield at High Elevation Sites During the first year when sediment yields were low, RUSLE overpredicted mean sediment yields by 0.2 ± 0.2 Mg/ha (Table 20). During the second year when larger amounts of sediment were moved, RUSLE on average underpredicted sediment yields by Table 20. RUSLE predicted and measured sediment yield values (Mg/ha) for all test plot treatments during 2000 and 2001. T reatm en t M easured S ed im en t Y ield* R U S L E P redicted S ed im en t Y ields Year 2000 Coversoil Coversoil/Pitting Coversoil/Slash Barriers Coversoil/AM Inoculum Control 0.15 0.04 0.09 0.08 0.21 0.50 0.09 0.25 0.50 0.23 Year 2001 Coversoil 1.68 Coversoil/Pitting 0.21 Coversoil/Slash Barriers 1.01 Coversoil/AM Inoculum 1.60 Control 1.34 * Means are an average of three replications. 0.56 0.20 0.29 0.56 0.32 48 1.0 ± 1.0 Mg/ha. RUSLE underpredicted sediment yields by 1.6 + 0.9 Mg/ha on plots that had an average annual rill severity rating of greater than 1.5. The rill formation factor constants calculated by Kapolka and Dollhopf (2001) were applied to the second year RUSLE analysis because rill fdrmation was active. The optiriiized RUSLE qutputs are presented in Table 21. Appropriate F Factors were selected for individual plots based upon mean annual rill severity for 2001. The optimized RUSLE estimated sediment yields on average overpredicted sediment yields only slightly by 0.03 ± 0.41 Mg/ha. Figure 9 is a comparison of the actual sediment yields, original RUSLE estimated sedijnent yields, and the optimized estimated sediment yields. The optimized sediment yields improved accuracy of the RUSLE predictions to within 97 % of the measured sediment yields. Thfese results provide evidence that the rill formation factor established by Kapolka and Dollhopf to reflect the larger sediment yields during active slope rilling at the Treasure Mine retains accuracy under different rainfall conditions. The rill formation factors may not apply to soils that have different physiochemical characteristics that affect a soil’s potential for rilling. Measured Sediment-Delivery Ratios for Pitting and Slash Barrier Treatments The influence of the mechanical treatments (Covfersoil/Pitting and Coversoil/Slash Barrier) in decreasing sediment yields was evaluatfed by calculating the ratio of sediment yield from the mechanical treatment and sediment yield from the Coversoil treatment to obtain a sediment-yield delivery ratio (Table 22). The sediment-yield delivery ratio was 0.14 for the Coversoil/Pitting treatment and 0.60 for the Coversoil/Slash Barriers. These 49 Table 21. Optimized RUSLE sediment yields (Mg/ha) using rill formation factors during 2001. R U SL E Factors T reatm en t R K F Kl LS C P Coversoil Coversoil Coversoil Coversoil/Pitting Coversoil/Pitting Coversoil/Pitting Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoil/AM Inoculum Coversoi I/AM Inoculum Coversoil/AM Inoculum Control Control Control 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.12 0.12 0.12 1.0 8.4 16.6 1.0 1.0 1.0 1.0 16.6 1.0 16.6 1.0 8.4 8.4 8.4 8.4 0.15 1.26 2.49 0.15 0.15 0.15 0.15 2.49 0.15 2.55 0.15 1.26 1.01 1.01 1.01 4.32 4.32 4.32 0.78 0.78 0.78 1.52 1.52 1.52 4.32 4.32 4.32 4.32 4.32 4.32 0.06 0.06 0.06 0.13 0.13 0.13 0.09 0.09 0.09 0.06 0.06 0.06 0.05 0.05 0.05 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 4.00 - 3.50 - 2.50 - 0.50 - Covcrsoil Pitting Covers oil/ Slash Barriers Coversoil/ AM Inoculum O p tim ized R U SL E Sed im en t Y ields 0.23 1.91 3.78 0.09 0.09 0.09 0.12 1.99 0.12 3.87 0.23 1.91 1.19 1.19 1.19 Control ♦ Measured Sediment Yield □ RUSLE Predicted Sediment Yield A Optimized RUSLE Sediment Yield Figure 9. Comparison of measured, RUSLE predicted, and optimized RUSLE sediment yields using rill formation factors on test plots during 2001. 50 Table 22. Measured sediment-delivery ratio values for Coversoil/Pitting and Coversoil/Slash Barrier treatments. T reatm ent Coversoil/Pitting Coversoil/Slash Barriers Sed im en t D elivery R atio 0.14 0.60 mechanical treatments are intended as short-term, temporary erosion control measures to provide adequate slope stability until vegetation is established. It is expected that the pits will gradually fill in with eroded soil and the slash barriers will degrade over time, and the resultant sediment-delivery ratios will correspondingly increase. 51 5. SUMMARY AND CONCLUSION th e objective of this study was to evaluate the effect of several erosion control measures on sediment yields on reclaimed steep slopes at the Treasure Mine and compare measured sediment yields to values predicted by Revised Universal Soil Loss Equation (RUSLE) Version 1.06. Results indicate a trend towards pitting of the soil surface as a potentially effective erosion control practice to prevent rill formation and reduce erosion rates. The Coversoil/Pitting treatment consistently had decreased sediment yield on all plots and within treatment variation was minimal. Sediment yields on all other treatments were highly variable. This variation could be attributed to rill formation that developed on some plots. Lower sediment yields measured on pitted slopes were attributed to the increased surface roughness on the soil surface prohibiting the downslope linedr trajectory of water flow and minimizing rill formation. Newly constructed coversoil and spoil backfill are highly erosive materials and susceptible to rilling especially when precipitation is intense. Pitting of the soil surface also increases slope storage of water. Therefore, erosion control efforts that increase the surface roughness such as pitting or gouging are ideal for mineland reclamation on steep slopes until vegetation is established. A good vegetative cover may take two or more years to develop. TTie short duration of the study (two years), limited vegetation development (< 17 % canopy cover), and low replication (n = 3) all limit the ability to detect treatment differences. Therefore, these results suggest that pitting of the soil surface is potentially an effective erosion control practice at the level of precipitation received during the study, preventing rill formation 52 and reducing sediment yields on steep slopes until vegetation can provides adequate slope stability. Results from this study indicate that the decreased rock cover in the treatments with coversoil application (36 —42 %) provided better plant growth than the Control. The increased rock cover in the Control provided no significant decreases in sediment yields. Runoff was not significantly different between any of the treatments during 2000 and 2001. Sediment yield was not related to runoff in either year. Rill severity was strongly related to runoff during 2000 when rilling was slight. Rill severity was not related to runoff during 2001 when the slopes were actively rilling. Mean biomass, canopy cover and basal cover were significantly higher on plots with a coversoil application during 2001 wheh compared to the Control. However, there were no significant differences in plant growth between treatments that received a coversoil application, indicating that the Coversoil/Pitting, Coversoil/Slash Barriers, and Coversoil/AM Inoculum treatment^ during the period of this study neither enhanced nor reduced plant growth when compared to the Coversoil treatment. Mycorrhizal fungi propagules were present in the coversoil and spoil backfill material. There were no differences between AM inoculated, coversoil, and no coversoil treatments in percent colonization of the roots by mycorrhizal fungi in H. vulgare. Inri. trachycaulum, the AM inoculum treated plots showed significantly higher mycorrhizal colonization levels, as compared to plant roots from the coversoil and no coversoil treat plots. However, there were no significant differences between any Of the above-ground 53 plant growth characteristics dn plots that received a coversoil application. Both plant species were colonized by AM fungi at a relatively high level, and there is probably no measurable ecological difference between 46 % and 53 % colonization rates found in A. trachycaulum. With such high colonization in both AM-treated and non-AM treated plots, we would expect to see no biomass differences between those treatments. AM inoculation in this study seems’to have been unnecessary, since AM propagules were already present in the coversoil and spoil backfill material. This AM inoculation treatment was not found to enhance either AM inoculation levels or plant growth. Sediment yield, runoff, and rill severity were not related to plant growth in 2001. The sandy loam texture, low organic matter content, and high coarse fragment percentage of the coversoil and spoil backfill are not ideal for plant establishment and may have impaired plant growth, especially during below normal precipitation years as experienced in this study. Vegetative cover may be slow or difficult to develop on this site. Vegetation reestablishment can be potentially limited by the effects of frequent drought patterns experienced during this study and common in semi-arid, climates. In addition, the sandy loam texture, low organic matter content, and loss of soil aggregation during removal and regrading make the soil highly erodible and vulnerable to rilling when bare of vegetation of vegetative cover is minimal. Erosion control measures such as crimp mulches are not an option due to the stoniness of the soil. Sediment yield was significantly related to measured factors during both years of study. Runoff was not related to measured factofs either year. Sediment yield during both years of study was highly related to maximum hourly precipitation, increase in rill 54 severity class and runoff (r = 0.99). Prediction of erosion during this study appeared to be estimated by maximum hourly precipitation, runoff and rilling activity on the plots. During the first year when erosion rates were small, RUSLE overpredicted mean sediment yields by 0.2 ± 0.2 Mg/ha. During the second year when larger amounts of sediment were moved, RUSLE on average underpredicted sediment yields by 1.0 ± 1.0 Mg/ha. RUSLE underpredicted sediment yields by 1.6 + 0.9 Mg/ha on plots that had an average annual rill severity rating of greater than 1.5. The rill formation factor constants calculated by Kapolka and Dollhopf (2001) were applied to the second year data and the optimized RUSLE estimated sediment yields on average overpredicted sediment yields only slightly by 0.03 ± 0.41 Mg/ha. The optimized sediment yields improved accuracy of the RUSLE predictions to within 97 % of the measured sediment yields. The rill formation factor calculated by Kapolka and Dollhopf using sediment data from a previous erosion analysis at the Treasure Mine during 1998 was highly effective in enhancing RUSLE’s ability to predict sediment yields on plots where rilling was moderate or greater. ■ The sediment-yield delivery ratio was 0.14 for the Coversoil/Pitting treatment and 0.60 for the Coversoil/Slash Barriers. These mechanical treatments are intended as short-­ term, temporary erosion control measures to prbvide adequate slope stability until vegetation is established. It is expected that the pits will gradually fill in with sedifnent and the slash barriers will degrade and the sediment-delivery ratios will correspondingly increase. These results indicate that RUSLE is an effective tool for predicting sediment yields on high elevation, steep slopes. The RUSLE successfully modeled the erosion control measures used during this study. 56 REFERENCES CITED Abdul-Kareem5A. W., and S.G. McRae. 1984. The effects on topsoil of long-term storage in stockpiles. Plant and Soil 76, 357-363. Brady5N. C. and R. R. Weil. 1996. The Nature and Properties of Soils. I Ith Edition. Prentice Hall5Upper Saddle River5New Jersey. 740 pp. Brooks5K. N., P.F. Folliott5H.M. Gregersen5and L.F. DeBano. 1997. Hydrology and Management of Watersheds. Iowa State University Press. 502 pp. Clark, R. 1980. Erosion Condition Classification System. Determination of Soil Erosion Condition Montana Revised Method. 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The effect of surface mining on the infectivity of vesicular-arbuscular mycorrhizal fungi. Australian Journal of Botany 35, 641-652. Jastrow5J.D., R.M. Miller and J. Lussenhop. 1998. Contributions of interacting biological mechanisms to soil aggregate stabilization in restored prairie. Soil Biology and Biochemistry. 30, 905-916. 57 REFERENCES CITED continued Kapolka, N.M. and D J. Dollhopf. 2001. Effect of slope gradient and plant growth on Soil Loss on Reconstructed Steep Slopes. International Journal of Surface Mining, Reclamation and Environment. 15, 86 - 99. Knighton, D. 1998. Fluvial forms and propesses. A new perspective. Oxford University Press, Inc., New York, NY. 383 pp. Lambert, D.H., D.E. Baker, and H. Cole, Jr. 1979. The role of mycorrhizae in the interactions of phosphorus with zinc, copper, and other elements. Soil Science Society of America Journal, 43, 976-980. Liberia, A.E. 1981. Effects of topsoil-storage duration on inoculum potential of vesicular-arbuscular mycorrhizae. In: Symposium on Surface Mining Hydrology, Sedimentology and Reclamation, University of Kentucky, Lexington, KY. pp 45-48 Miller, R.M. and J.D. Jastrow. 1992. Mycorrhizal Functioning: An Integrative PlantFungal Process. Allen, M. F.[ed.]. Chapman & Hall, New York. 534 pp. Montana. 1973. Metal Mine Reclamation Act. Title 82. Chapter 4. Part 3. Montana. 1973. Strip and Underground Mine Siting Act. Title 82. Chapter 4. Part I. Nearing, M.A. 1997. A single, continuous function for slope steepness influence on soil loss. Soil Science Society Journal of America. 61, 917-919. Nelson, D.W. and L.E. Sommers. 1982. Total carbon, organic carbon, and organic matter. Methods of Soil Analysis - Part 2. American Society of Agronomy. Madison, WL 1159 pp. Osterkamp, W.R. and T.J. Toy. 1994. The healing of disturbed hillslopes by gully gravure. Geological Society of America Bulletin. 106,1233-1241. Renard, K.G. and V.A. Ferreira. 1993. RUSLE model description and database sensitivity. Journal of Environmental Quality. 22,458-466. 58 REFERENCES CITED continued Renard5K.G., G.R. Foster5GA. Weesies5D.K. McCool andD.C. Yoden [Coordinators], 1997. Predicting soil erosion by water: A guide to conservation planning with the Revised Universal Soil Loss Equation (RUSLE)5U.S. Department of Agriculture, Agriculture Handbook No. 703, 404 pp. Rhoades5LD. 1982. Soluble salts. Methods of Soil Analysis - Part 2. American Society of Agronomy. Madison5WL 1159 p. Rives5C.S., MT. Bajwa5A.E. Liberia and R.M. Miller. 1980. Effects of topsoil storage during surface mining qn the viability of VA mycorrhiza. Soil Science 129,253257. Shetty5K.G., B A D. Hetrick and A.P. Schwab. 1995. Effects of mycorrhizae and fertilizer amendments on zinc tolerance of plants. Environmental Pollution. 88, pp 307-314. Smith5S.E. and D.J. Read. 1997. Mycorrhizal Symbiosis. Academic Press. New York5 New York. 605 pp. Stark5J.M. and E.F. Redente. 1987. Production potential of stockpiled topsoil. Soil Science 144, 72-76. Taiz5L. and E. Zeiger. 1998. Plant Physiology. 2nd Edition. Sihauer Associates, Inc. Sunderland, MA. 792 pp Tmker5P.B. and Gildon5A. 1983. Mycorrhizal fungi and ion uptake. In Metals and Micronutrients: Uptake and Utilization by Plants, DA. Robb and W.S. Pierpoint5 eds., Academic Press5New York5pp. 21-32. Toy, T. J., G.R. Foster and K. G. Renard. 1999. RUSLE for mining, construction and reclamation lands. Journal of Soil and Water Conservation. 54,462-467. Toy, T.J. and G.R. Foster (eds). 1998. Guidelines for the use of the Revised Universal Soil Loss Equation on mined lands, construction sites, and reclaimed lands. Office of Surface Mining5Reclamation, and Enforcement, 149 pp. + software. Toy, T.J, and W.R. Osterkamp, 1995. The applicability of RUSLE to geomoiphic studies. Journal of Soil & Water Conservation5 Special Issue: Water Research and Management in Semiaiid Environments. 50,498-504. U.S. Congress. 1972. Clean Water Act of 1972. Public Law 95-217. 59 REFERENCES CITED continued U.S. Congress. 1977. Surface Mining Control and Reclamation Act of 1977. Public Law 95-87. USDA NRCS. June 2000. National Agronomy Manual. 3rd Edition. Part 501, 190-VNAM.' Vangronsveld, J., J.V. Colpaert and K.K. Van Tichelen. 1996. Reclamation of a bare industrial area contaminated by non-ferrous metals: physicochemical and biological evaluation of the durability of soil treatment and revegetation. Environmental Pollution. 94, 131-140. Visser, S., C.L. Griffiths and D. Parkinson. 1984. Topsoil storage effects on primary production and rates of vesicular-arbuscular mycorrhizal development in Agropyron trachycaulum. Plant and Soil. 82,51-60. Western Regional Climate Center. 2002. Climate and weather information. www.wrcc.dri.edu/summarv. Yoder, D. and J. Town. 1995. The future of RUSLE: inside the new Revised Universal Soil Loss Equation. Journal of Soil & Water Conservation. Special Issue: Water Research and Management in Semiarid Environments. 50,484-490. . 60 APPENDICES APPENDIX A SOIL PHYSIOCHEMICAL DATA 62 Table 23. Coversoil textural analyses. S am p le Sand (% ) I 2 62.5 62.5 S ilt C lay (%) 20 20 (%) 17.5 17.5 Soil T extu re Sandy loam Sandy loam Table 24. Coversoil pH and EC analyses. EC (m m hos/cm ) pH 6.63 6.56 6.64 Sam ple I 2 3 0.94 0.84 0.78 Table 25. Subsoil textural analyses. S am p le Sand (% ) I 2 60.0 62.5 Silt C lay (%) 17.5 17.5 (%) 22.5 22.5 Soil T exture Sandy loam Sandy loam Table 26. Subsoil pH and EC analyses. S am p le I 2 3 pH 7.26 7.36 7.42 EC (m m hos/cm ) 1.19 1.18 1.10 APPENDIX B PRECIPITATION DATA 64 Table 27. Monthly precipitation (cm) for Dillon, Montana (WMCE), 2000. M onth P recipitation D eviation January 1.14 -0.28 February 1.52 0.30 March 1.80 -0.41 April 0.23 -3.20 May 6.15 0.23 June 3.20 -2.46 July 1.32 -1.91 August 1.68 -1.19 September 0.99 -2.01 October 5.69 3.63 November 1.98 0.46 December 0.28 -1.02 Total 25.98 -8.20 65 Table 28. Monthly precipitation (cm) for Dillon, Montana (WMCE), 2001. M onth P recipitation D eviation January 0.13 -1.30 February 0.05 -1.17 March 0.36 -1.85 April 3.53 0.10 May 0.61 -5.31 June 6.78 1.12 July 2.72 -0.51 August 0.00 -2.87 September 2.44 -0.56 October 1.57 -0.48 November 0.74 -0.79 December 3.02 1.73 Total 21.95 -12.24 66 Table 29. Precipitation (cm) at Treasure Mine, June 20 -30, 2000. D ate T im e Precipitation 27 1300 0.1 67 Table 30. Precipitation (cm) at Treasure Mine, July 2000. Date Time Precipitation I 1600 1700 0.3 0.1 2 1700 0.2 3 3 800 1200 0.1 0.1 4 1400 0.1 6 400 0.1 68 Table 31. Precipitation (cm) at Treasure Mine, August 2000. D ate T im e Precipitation 10 2400 0.1 15 1100 0.1 26 2000 0.1 69 Table 32. Precipitation (cm) at Treasure Mine, September 2000. D ate T im e P recipitation 4 200 0.1 5 1500 0.1 10 1900 0.1 11 600 0.1 16 1400 0.1 19 600 700 1500 0.1 0.2 0.1 23 1700 1800 1900 0.1 0.1 0.2 24 1100 0.1 30 1200 0.1 70 Table 33. Precipitation (cm) at Treasure Mine, October I - October 10, 2000. D ate T im e P recipitation I 100 900 1000 1100 1200 0.4 0.1 0.2 0.3 0.1 10 2300 2400 1.7 0.6 71 Table 34. Precipitation (cm) at Treasure Mine, May 4 - May 31, 2001._________ ___________ D ate________________________ T im e____________________ Precipitation 27 1200 0.1 72 Table 35. Precipitation (cm) at Treasure Mine, June 2001. D ate T im e P recipitation 2 1400 1600 1700 1800 0.1 0.1 0.1 0.1 3 1200 1300 1400 0.2 0.4 0.6 6 1700 0.2 10 2400 0.1 11 100 1300 1500 1700 1800 1900 2000 0.1 0.3 0.2 0.1 0.1 0.1 0.1 12 1500 1600 2100 2200 2300 2400 0.1 0.1 0.4 0.2 0.2 0.1 13 100 200 900 1100 1200 0.1 0.1 0.1 1.0 0.5 16 2200 0.2 17 100 0.1 23 1600 0.1 26 200 0.1 28 1800 0.1 73 Table 36. Precipitation (cm) at Treasure Mine, July 2001. D ate T im e P recipitation 4 1300 2000 0.2 0.2 5 1700 0.2 8 1700 1800 1900 0.1 0.4 0.2 10 1800 0.1 11 1700 0.1 12 1600 0.2 14 1200 1600 1700 0.1 0.1 0.7 15 900 2100 0.2 0.1 16 400 1800 2200 2300 0.1 0.2 0.1 0.3 19 500 0.1 20 1200 1300 0.1 0.1 27 1300 0.1 30 200 400 500 0.1 0.4 0.2 74 Table 37. Precipitation (cm) at Treasure Mine, August 2001. D ate T im e P recipitation 3 1400 0.1 75 Table 38. Precipitation (cm) at Treasure Mine, September 1 - 17, 2001. D ate T im e Precipitation 4 2100 0.3 5 200 300 600 1700 0.2 0.3 0.7 0.9 6 1400 0.1 13 1400 0.6 17 1200 0.2 76 Table 39. Evaporation (cm) at Treasure Mine, 2000 and 2001. D ates E vap oration Year 2000 6/20/00 - 7/12/00 5.7 7/12/00-7/27/00 5.8 7/27/00-8/15/00 6.1 8/15/00 - 8/29/00 3.2 8/29/00 - 9/16/00 1.2 9/16/00 - 9/30/00 1.9 9/30/00- 10/18/00 1.6 Year 2001 5/4/01-5/14/01 2.4 5/14/01-5/28/01 5.4 5/28/01-6/12/01 2.5 7/5/01-7/21/01 6.8 7/21/01 - 8/5/01 5.4 8/5/01 - 8/18/01 6.4 8/18/01-9/3/01 1.5 9/3/01-9/18/01 5.2 9/18/01 - 10/10/01 3.7 77 APPENDIX C SEDIMENT YIELD AND RUNOFF DATA 78 Table 40. Sediment yield (kg) on test plots, 2000. A ug 2 D ate S ept 16 O ct 19 Coversoil 1.19 0.77 14.07 Coversoil 0.68 1.25 0.68 Coversoil 0.58 0.65 0.58 Coversoil/Pitting 0.28 1.22 0.13 Coversoil/Pitting 1.28 0.63 0.00 Coversoil/Pitting 0.62 0.90 0.68 Coversoil/Slash Barriers 0.37 0.58 0.23 Coversoil/Slash Barriers 1.97 1.30 5.65 Coversoil/Slash Barriers 0.60 0.75 0.60 CoversoiI/AM Inoculum 0.43 0.49 0.17 Coversoil/AM Inoculum 1.18 0.71 0.27 Coversoil/AM Inoculum 1.33 1.12 4.80 Control 0.16 0.86 17.14 Control 1.73 1.09 1.22 Control 0.91 1.45 4.68 T reatm en t 79 Table 41. Sediment yield (kg) on test plots, 2001. Ju ly 21 D ate A u gu st 5 Sep tem b er 18 Coversoil 45.66 13.56 94.55 Coversoil 13.11 56.18 47.33 Coversoil 4.65 99.77 0.00 Coversoil/Pitting 9.39 1.19 0.00 Coversoil/Pitting 4.26 7.26 0.00 Coversoil/Pitting 1.33 6.07 0.00 Coversoil/Slash Barriers 11.63 65.66 0.00 Coversoil/Slash Barriers 4.00 4.23 0.00 Coversoil/Slash Barriers 42.65 11.55 47.53 Coversoil/AM Inoculum 15.61 30.79 117.84 Coversoil/AM Inoculum 6.98 18.56 0.00 Coversoil/AM Inoculum 14.70 136.17 23.55 Control 35.87 40.24 23.66 Control 22.87 24.69 0.28 Control 28.60 33.62 23.98 T reatm en t 80 Table 42. Depth (cm) of runoff in troughs at test plots, 2000. Ju ly 12 Ju ly 27 A ug 15 D ate A ug 27 Sept 16 Sept 30 O ct 19 Coversoil 0 0 0 0 0 0 28 Coversoil 0 0 0 0 0 0 20 Coversoil 0 0 0 0 0 0 19.5 Coversoil/Pitting 0 0 0 0 0 0 18.5 Coversoil/Pitting 0 0 0 0 0 0 20 Coversoil/Pitting 0 0 0 0 0 0 20 Coversoil/Slash Barriers 0 0 0 0 0 0 20 Coversoil/Slash Barriers 0 0 0 0 0 0 24 Coversoil/Slash Barriers 0 0 0 0 0 0 20 Coversoil/AM Inoculum 0 0 0 0 0 0 19.5 Coversoil/AM Inoculum 0 0 0 0 0 0 20.5 Coversoil/AM Inoculum 0 0 0 0 0 0 22 Control 0 0 0 0 0 0 41.9 Control 0 0 0 0 0 0 24 Control 0 0 0 0 0 0 21 T reatm ent 81 Table 43. Depth (cm) of runoff in troughs at test plots, 2001. T reatm ent D ate A u gu st S ept 3 Ju n e Ju ly 5 Ju ly Coversoil 8 34.3 19.8 22 0 14.4 Coversoil 7.8 11.5 17.2 16.75 0 9.2 Coversoil 7.3 4.3 10.5 7 0 8.8 Coversoil/Pitting 7.3 7 18 12 0 7.4 Coversoil/Pitting 7.9 12.5 11.1 8.25 0 7.1 Coversoil/Pitting 7.7 10.7 7.9 2.3 0 6.2 Coversoil/Slash Barriers 8 6.9 12.5 8 0 7.7 Coversoil/Slash Barriers 8.6 14.2 9 5 0 7.9 Coversoil/Slash Barriers 8 10.5 28.8 34 0 22.3 Coversoil/AM Inoculum 7.3 8.3 21 30 0 7.4 Coversoil/AM Inoculum 7.9 9.2 13.2 7.5 0 7.3 CoversoiI/AM Inoculum 7.5 18.6 11.9 8 0 7.1 Control 7.6 8.1 25.4 15 0 25.6 Control 8.1 29 20.2 13.5 0 19.2 Control 9 32.2 30.8 15.5 0 26 S ept 82 Table 44. Rill severity (class) on test plots, 2000. 7/12 7/27 8/15 D ate 8/27 9/16 9/30 10/19 Coversoil I I I I I I I Coversoil I I I I I I I Coversoil I I I I I I 3 Coversoil/Pitting I I I I I I I Coversoil/Pitting I I I I I I I Coversoil/Pitting I I I I I I I Coversoil/Slash Barriers I I I I I I I Coversoil/Slash Barriers I I I I I I I Coversoil/Slash Barriers I I I I I I 2 Coversoil/AM Inoculum I I I I I I I Coversoil/AM Inoculum I I I I I I I Coversoil/AM Inoculum I I I I I I 2 Control I I I I I I I Control I I I I I I I I I 2 T reatm en t Control I I I I Class: I = stable, 2 = slight, 3 = moderate, 4 = critical, 5 = severe 83 Table 45. Rill severity (class) on test plots, 2001.__________ T reatm ent 5/14 5/28 6/12 7/5 Coversoil 2 2 2 2 Coversoil 2 2 2 Coversoil 3 3 Coversoil/Pitting I Coversoil/Pitting D ate 7/21 8/5 9/3 9/18 3 3 3 3 2 4 4 4 4 3 3 4 4 4 4 I I I 2 2 2 2 I I I I 2 2 2 2 Coversoil/Pitting I I I I 2 2 2 2 Coversoil/Slash Barriers 2 2 2 2 3 3 3 3 Coversoil/Slash Barriers 2 2 2 2 3 4 4 4 Coversoil/Slash Barriers 2 2 2 2 2 2 2 2 Coversoil/AM Inoculum 2 2 2 2 3 5 5 5 Coversoil/AM Inoculum 2 2 2 2 3 3 3 3 Coversoil/AM Inoculum 2 2 2 2 3 3 3 3 Control 2 2 2 2 3 3 3 3 Control 3 3 3 3 4 4 4 4 4 4 4 Control 3 3 3 3 4 Class: I = stable, 2 = slight, 3 = moderate, 4 = critical, 5 = severe 84 APPENDIX D VEGETATION DATA I 85 Table 4 6 . Perennial grass canopy cover (%) on test plots, 2001. Fram e N um b er Plot I 2 3 4 5 6 7 8 9 10 Coversoil 2 I I 2 I I 2 2 2 I Coversoil 2 2 I 2 I I I I I I Coversoil I I I 2 I I 2 I 2 I Coversoil/Pitting 0 I I 2 I I 0 0 I 0 Coversoil/Pitting 2 2 2 I I I 2 I I I Coversoil/Pitting I 2 I 2 I 2 I 2 I 2 Coversoil/Slash Barriers I I I 2 I I I 2 I I Coversoil/Slash Barriers I 2 I I I I 2 2 I I Coversoil/Slash Barriers 2 I 2 I I I I I I I Coversoil/AM Inoculum 2 2 I I I I I I I 2 Coversoil/AM Inoculum I I I 3 2 2 I I 2 I Coversoil/AM Inoculum 2 I I I 2 I 3 2 I I Control I I I I I I 0 I I I Control I I I I I I I I I I Control I I I I I I I 0 I 0 Cover class: I = O- 10 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 5 1 - 60% 10 = 9 1 - 100% 3 = 2 1 - 30% 7 = 6 1 - 70% 4 = 3 1 - 40% 8 = 71 - 80% 86 Table 47. Forb canopy cover (%) on test plots, 2001. Fram e N um b er 5 6 7 Plot I 2 3 4 Coversoil I 0 I 0 I I Coversoil I I 0 I I Coversoil I 2 I I Coversoil/Pitting I I I Coversoil/Pitting I 2 Coversoil/Pitting I Coversoil/Slash Barriers 8 9 10 I I I I 0 0 I 0 0 I 2 I 2 0 I I I I I 0 I I I I 2 0 0 I 0 I I 0 I I 0 2 2 I I I I I I 2 2 I I I I Coversoil/Slash Barriers 0 I I I I 0 I I 0 I Coversoil/Slash Barriers I I I 2 I 0 I I I 2 Coversoil/AM Inoculum I I 0 I I I I I 2 I Coversoil/AM Inoculum 2 I 0 I I I I 2 I I Coversoil/AM Inoculum I I 2 2 I 2 2 0 I I Control I 0 0 0 I I 0 I I 0 Control 0 I I I I I 0 I I 0 Control 0 0 I 0 0 I 0 0 0 I Cover class: I = 0 -1 0 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 51 60% 10 = 91 100% — 3 = 21 - 30% 7 = 6 1 - 70% 4 = 3 1 - 40% 8 = 7 1 - 80% 87 Table 48. Annual grass canopy cover (%) on test plots, 2001. F ram e N um b er Plot I 2 3 4 5 6 7 8 9 10 Coversoil 0 I 0 0 0 0 0 0 0 0 Coversoil I 0 0 0 0 I 0 0 I 0 Coversoil I 0 2 0 0 0 0 I 0 0 Coversoil/Pitting I I 0 I I 2 0 I I I Coversoil/Pitting 0 0 0 0 0 0 0 0 0 I Coversoil/Pitting 0 I I 0 0 0 0 0 0 I Coversoil/Slash Barriers I I 0 I I 0 0 0 0 I Coversoil/Slash Barriers 0 0 0 0 I 2 0 0 0 0 Coversoil/Slash Barriers 0 I I 0 0 0 0 I I 0 Coversoil/AM Inoculum I I I I 2 I I 2 2 I Coversoil/AM Inoculum 0 0 I 0 0 0 I I 0 0 Coversoil/AM Inoculum I I 0 0 0 0 0 0 I 0 Control I 0 I I 0 0 I 0 0 0 Control I 0 0 0 0 I I 0 0 0 Control 0 0 0 0 0 0 0 0 0 0 Cover class: I = 0 -1 0 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 5 1 -6 0 % 10 = 9 1 -1 0 0 % 3 = 21 - 30% 7 = 6 1 - 70% 4 = 3 1 - 40% 8 = 71 - 80% 88 Table 49. Perennial grass basal cover (%) on test plots, 2001.______ _____ I 2 Plot 3 4 F ram e N um b er 5 6 7 8 9 10 Coversoil I I I I I I I I I I Coversoil I I I I I I I I I I Coversoil I I I I I I I I I I Coversoil/Pitting 0 I I I I I 0 0 I 0 Coversoil/Pitting I I I I I I I I I I Coversoil/Pitting I I I I I I I I I I Coversoil/Slash Barriers I I I I I I I I I I Coversoil/Slash Barriers I I I I I I I I I I Coversoil/Slash Barriers I I I I I I I I I I Coversoil/AM Inoculum I I I I I I I I I I Coversoil/AM Inoculum I I I I I I I I I I Coversoil/AM Inoculum I I I I I I I I I I Control I I I I I I 0 I I I Control I I I I I I I I I I Control I I I I I I I 0 I 0 Cover class: I = 0 -1 0 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 5 1 -6 0 % 10 = 91 - 100% 3 = 2 1 -3 0 % 7 = 6 1 -7 0 % 4 = 3 1 -4 0 % 8 = 7 1 -8 0 % 89 Table 50. Forb basal cover (%) on test plots. 2001. Frame Number 5 6 7 Plot I 2 3 4 Coversoil I 0 I 0 I I Coversoil I I 0 I I Coversoil I I I I Coversoil/Pitting I I I Coversoil/Pitting I I Coversoil/Pitting I Coversoil/Slash Barriers 8 9 10 I I I I 0 0 I 0 0 I I I I 0 I I I I I 0 I I I I I 0 0 I 0 I I 0 I I 0 I I I I I I I I I I I I I I Coversoil/Slash Barriers 0 I I I I 0 I I 0 I Coversoil/Slash Barriers I I I I I 0 I I I I Coversoil/AM Inoculum I I 0 I I I I I I I Coversoil/AM Inoculum I I 0 I I I I I I I Coversoil/AM Inoculum I I I I I I I 0 I I Control I 0 0 0 I I 0 I I 0 no coveroil 0 I I I I I 0 I I 0 Control 0 0 I 0 0 I 0 0 0 I Cover class: 1= 0 - 1 0 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 5 1 -6 0 % 10 = 91 - 100 % 3 = 21 - 3 0 % 7 = 6 1 -7 0 % 4 = :3 1 -4 0 % 8 = '71 - 80 % 90 Table 51. Annual grass basal cover (%) on test plots, 2001. Fram e N um b er Plot I 2 3 4 5 6 7 8 9 10 Coversoil 0 I 0 0 0 0 0 0 0 0 Coversoil I 0 0 0 0 I 0 0 I 0 Coversoil I 0 I 0 0 0 0 I 0 0 Coversoil/Pitting I I 0 I I I 0 I I I Coversoil/Pitting I 0 0 0 0 0 0 0 0 I Coversoil/Pitting 0 I I 0 0 0 I I 0 I Coversoil/Slash Barriers I I 0 I I I I I I I Coversoil/Slash Barriers 0 0 0 0 I I 0 0 0 0 Coversoil/Slash Barriers 0 I I 0 I 0 0 I I I Coversoil/AM Inoculum I I I I I I I I I I Coversoil/AM Inoculum 0 0 I 0 0 0 I I 0 0 Coversoil/AM Inoculum I I I 0 0 0 0 0 I 0 Control I 0 I I 0 0 I 0 0 0 Control I 0 0 0 0 I I 0 0 0 Control 0 0 0 0 0 0 0 0 0 0 Cover class: I = 0 - 10 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 51 - 60 % 10 = 91 - 100% 3 = 2 1 - 30% 7 = 6 1 - 70% 4 = 31 - 40% 8 = 71 - 80% 91 Table 52. Rock cover (%) on test plots, 2001. F ram e N um b er 5 6 7 Plot I 2 3 4 Coversoil 3 4 4 5 4 4 Coversoil 5 3 5 2 5 Coversoil 3 3 4 3 Coversoil/Pitting 7 7 6 Coversoil/Pitting 5 3 Coversoil/Pitting 4 Coversoil/Slash Barriers 8 9 10 4 5 4 7 3 6 7 3 3 3 4 5 4 3 4 5 6 7 6 7 8 4 5 5 5 5 6 6 4 3 4 4 3 4 4 5 5 4 2 6 5 5 6 4 4 6 4 5 5 Coversoil/Slash Barriers 5 6 4 4 5 6 3 4 7 4 Coversoil/Slash Barriers 3 2 3 5 4 4 3 5 4 3 Coversoil/AM Inoculum 5 5 4 4 5 6 6 5 5 6 Coversoil/AM Inoculum 4 4 6 4 4 5 4 5 3 4 Coversoil/AM Inoculum 4 5 5 5 6 5 4 4 5 3 Control 6 6 6 6 4 5 6 4 5 6 Control 6 7 6 6 5 6 7 5 5 5 Control 8 8 7 7 8 8 8 8 8 8 Cover class: I = 0 - 10 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 5 1 -6 0 % 10 = 91 - 100 % 3 = 21 - 30% 7 = 61 - 70% 4 = 31 - 40% 8 = 7 1 - 80% 92 Table 53. Bare ground cover (%) on test plots, 2001. F ram e N um b er 5 6 7 Plot I 2 3 4 Coversoil 7 7 6 5 6 7 Coversoil 6 8 6 8 5 Coversoil 7 7 7 7 Coversoil/Pitting 2 2 3 Coversoil/Pitting 6 7 Coversoil/Pitting 6 Coversoil/Slash Barriers 8 9 10 6 5 6 4 7 4 4 7 7 7 6 6 6 7 6 5 4 3 4 3 3 6 6 6 6 6 5 5 7 7 6 7 7 6 7 6 5 6 8 5 7 5 4 6 6 4 6 6 5 Coversoil/Slash Barriers 5 4 6 7 5 4 7 6 3 6 Coversoil/Slash Barriers 7 8 7 5 6 7 7 5 6 7 Coversoil/AM Inoculum 5 5 6 6 5 4 4 5 5 4 Coversoil/AM Inoculum 6 7 4 6 6 5 6 5 7 7 Coversoil/AM Inoculum 6 6 5 5 4 5 6 7 6 7 Control 4 5 5 4 6 5 4 6 7 4 Control 5 4 5 5 5 5 4 5 5 5 Control 2 2 3 3 2 3 2 2 2 2 Cover class: I = O - 10 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 51 - 60% 10 = 9 1 - 100% 3 = 2 1 - 30% 7 = 61 - 70% 4 = 31 - 40% 8 —71 - 80% 93 Table 54. Perennial grass biomass (g) on test plots, 2001. Plot I Coversoil 0.54 Coversoil 0.39 0.94 Coversoil 2 0.4 4 3 0 F ram e N um b er 5 6 7 0 0.51 1.04 0.77 1.68 0.4 2.03 1.32 8 1.19 1.05 1.15 0.65 5.77 Coversoil/Pitting 0.19 0.64 0.52 1.02 0.2 0.29 0.47 Coversoil/Pitting 2.29 0.41 0 2.12 0.32 0.34 Coversoil/Pitting Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoil/AM Inoculum Coversoil/AM Inoculum Coversoil/AM Inoculum 0.29 0.27 0 4.56 0.78 0.55 0.45 0.11 0.2 0.32 2.81 1.11 0.41 0.68 0.22 0.62 0.31 1.75 0 0.75 1.33 1.49 1.48 0 1.16 0 9.02 1.41 0.02 0.89 1.55 1.25 2.22 0.17 0.26 0.46 1.67 0.73 0.36 0.16 Control 0.27 0.16 0.08 0.31 Control 0.01 0.1 0.03 0 0.19 0.2 1.25 1.97 0.92 1.15 0.35 0.55 0.39 0.13 0.25 1.26 0.93 0 0.03 2.35 0.18 0.83 Control 1.65 2.54 1.55 0.3 0.08 0.27 1.37 0.83 0.55 0.34 10 1.45 0.32 0.25 0 0.77 1.59 0.38 1.7 1.05 9 1.3 1.31 8.45 1.9 4.59 2.61 1.67 3.99 5.06 1.25 0.36 0 0 0 1.49 1.1 0 0.03 0 0.34 0 0.4 0.34 0.26 0.13 0.35 0.63 0 0.12 0.2 0.01 0.02 0.01 0.18 94 Table 55. Forb biomass (g) on test plots, 2001. F ram e N um b er 5 6 7 Plot I 2 3 4 Coversoil 2.23 0.91 0.14 0.00 0.09 0.10 Coversoil 0.53 1.58 4.12 0.00 1.88 Coversoil 2.09 1.64 0.56 0.14 Coversoil/Pitting 2.86 0.00 0.11 Coversoil/Pitting 0.43 0.00 Coversoil/Pitting Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoil/Slash Barriers Coversoi 1/AM Inoculum Coversoil/AM Inoculum Coversoil/AM Inoculum 0.00 8 9 10 0.25 0.31 0.20 0.00 0.00 0.00 0.48 0.07 0.00 0.25 3.82 1.00 0.08 0.00 0.07 0.12 0.00 0.62 0.00 0.19 0.00 0.00 0.00 0.16 0.72 0.26 0.00 0.09 0.07 0.90 0.00 0.00 0.25 0.09 0.00 0.00 0.46 0.00 1.62 0.12 0.32 0.02 3.83 0.00 3.93 0.00 1.07 0.10 0.00 1.35 0.20 0.05 2.38 0.07 0.15 2.71 0.00 0.09 0.00 2.27 1.38 0.03 2.18 3.04 0.81 0.87 0.53 0.00 0.00 0.00 0.12 0.37 0.15 0.00 0.00 0.00 0.18 0.00 0.00 0.01 0.00 0.31 0.00 0.00 1.75 0.09 0.00 0.00 0.12 0.07 0.00 0.03 0.06 0.03 0.01 0.00 2.89 0.00 0.20 Control 0.00 0.00 0.00 0.00 0.00 0.24 0.00 0.00 0.21 0.00 Control 0.32 0.15 0.70 0.00 0.15 0.00 0.00 0.17 0.20 0.14 Control 0.00 0.00 0.00 0.01 0.03 0.07 0.08 0.00 0.00 0.00 95 Table 56. Annual grass biomass (g) on test plots, 2001. Fram e N um b er Plot I 2 3 4 5 6 7 8 9 10 Coversoil O O O O O 0 0 0 0 0 Coversoil O O O O 0.88 0 0 0 0 0 Coversoil O O O O 0 0 0 0 0 0 Coversoil/Pitting O O O O 0 0 0 0 0 0 Coversoil/Pitting O O O O 0 0 0 0 0 0 Coversoil/Pitting O O O O 0 0 0 0 0 0 Coversoil/Slash Barriers O O O O 0 0 0 0 0 0 Coversoil/Slash Barriers O O O O 0 0 0 0 0 0 Coversoil/Slash Barriers O O O O 0 0 0 0 0 0 Coversoil/AM Inoculum O O O O 0 0 0 0 0 0 Coversoil/AM Inoculum O O O O 0 0 0 0 0 0 Coversoil/AM Inoculum O O O O 0 0 0 0 0 0 Control O O O O 0 0.03 0 0 0.63 0 Control O O O O 0 0 0 0 0 0 Control O O O O 0 0 0 0 0 0 96 Table 57. Vegetative litter cover (class) on test plots, 2001. F ram e N um b er 5 6 7 Plot I 2 3 4 Coversoil I I I I I I Coversoil I I I I I Coversoil I I I I Coversoil/Pitting I I I Coversoil/Pitting I I Coversoil/Pitting I Coversoil/Slash Barriers 8 9 10 I I I I I I I I I I I I I I I I I I 0 0 I I I I I I I I I 0 I I I I 0 I I I I I I I I I I I I I I Coversoil/Slash Barriers I I I I I I I I I I Coversoil/Slash Barriers I I I I I I I I I I Coversoil/AM Inoculum I I I I I I I I I I Coversoil/AM Inoculum 0 I I I I I I I I I Coversoil/AM Inoculum 0 I I I I I I I I 0 Control 0 0 0 0 0 0 0 0 0 0 Control I I I I I I I I I I Control 0 0 0 0 0 0 0 0 0 0 Cover class: 1= 0 - 1 0 % 5 = 4 1 -5 0 % 9 = 8 1 -9 0 % 2 = 11-20% 6 = 51 - 60 % 10 = 9 1 -1 0 0 % 3 = 21 - 30% 7 = 6 1 - 70% 4 = 31 - 40% 8 = 71 - 80% 97 Table 58. Percent colonization by vesicular arbuscular mycorrhizal fungi in coversoil ________ and spoil backfill material, 2000.__________________ T reatm ent Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material Spoil Backfill Material * Arcsine transformation N onAM H yp h ae H yp h ae V esicles A rb uscu les I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 35 38 44 37 51 18 35 29 21 15 42 17 23 35 15 27 38 31 2 3 2 I 0 0 0 4 0 4 3 5 5 0 3 0 0 0 0 0 0 0 0 0 I 0 0 0 0 0 0 0 0 0 0 0 N one % AM colon .*+ 58 39% 55 43% 50 48% 58 40% 46 53% 30 38% 60 38% 63 34% 75 22% 80 19% 51 47% 74 23% 68 29% 61 36% 78 19% 69 28% 58 40% 65 32% {hyphae + vesicles + arbuscules) +% AM calculated as (total observations) 98 Table 59. Percent colonization by vesicular arbuscular mycorrhizal fungi in Hordeum vulgare, 2001. T reatm en t Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Control Control Control Control Control Control Control Control Control Control Control Control Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. N onAM H yp h ae 2 O 3 O O O 6 O O I O O 4 O 2 O O O O 2 O 4 O O H yp h ae V esicles A rb uscules N one % AM colon. *+ 41 O O 53 44% 39 O O 57 42% 20 I O 72 22% 31 O O 65 33% 39 I I 55 44% 43 2 O 51 49% 20 I O 69 22% 30 3 O 63 35% 32 3 O 61 37% 17 O O 78 18% 23 I O 72 25% 19 O O 29 41% 25 7 O 60 34% 32 O O 64 34% 28 I O 65 31% 32 O O 64 34% 42 I O 53 46% 8 O O 88 8% 37 O O 59 40% 42 O I 51 46% 16 O O 32 34% 31 O O 61 33% 17 O O 31 36% 34 O O 62 36% I 25 O O 70 26% O 20 5 O 71 26% O 37 O O 59 40% O 32 O O 64 34% O 27 I O 68 30% 2 19 6 O 69 26% I 27 I O 67 30% 3 12 O O 33 25% O 48 9 I 38 65% 2 35 O O 59 37% I 33 O O 62 35% I 40 I O 54 44% (intersections with hyphae, vesicles, or arbuscules) * Arcsine transformation +% AM (total intersections) 99 Table 60. Percent colonization by vesicular arbuscular mycorrhizal fungi in Agropyron trachycaulum, 2001. T reatm ent Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Coversoil Control Control Control Control Control Control Control Control Control Control Control Control Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. Coversoil/AM Inoc. N onAM H yp h ae 3 O O 3 6 2 2 O O 4 I O O O I I O I O O O O O O O O O O 2 O O I O I O O H yp h ae V esicles A rb uscu les N one % AM colon.** 46 I I 45 52% 41 2 O 53 46% 21 2 O 25 50% 20 I I 23 48% 39 O O 51 42% 38 O I 55 42% 48 O O 46 52% 35 3 O 41% 58 44 I I 50 50% 37 O O 55 40% 31 O O 64 33% 47 I O 48 52% 42 I O 53 46% 41 O 2 53 46% 42 5 O 48 51% 22 5 O 20 60% 38 I O 57 42% 41 4 O 50 49% 31 2 O 63 35% 43 2 O 51 49% 30 5 O 61 37% 31 2 O 63 35% 20 I O 27 45% 16 I O 31 36% 46 3 O 47 54% 38 12 4 42 60% 56 2 O 38 65% 27 O O 21 60% 50 O O 44 55% 47 2 O 47 54% 39 4 O 53 46% 37 O O 58 40% 46 3 O 47 54% 49 O I 45 55% 42 O O 54 45% 23 O O 25 50% (intersections with hyphae, vesicles, or arbuscules) * Arcsine transformation +% AM (total intersections) 100 APPENDIX E . STATISTICAL ANALYSIS , 101 Table 61. Two way analysis of variance of sediment yield, 2000. S tatistical A nalysis R esults_______________ General Linear Model (No Interactions) Dependent Variable: 2000 Total Sediment Yield (Mg/ha) Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 0.0529 0.100 0.0375 0.191 MS 0.0132 0.0500 0.00469 0.0136 F P 2.820 0.099 10.659 0.006 The difference in the mean values among the different levels of TRT is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REP. There is not a statistically significant difference (P = 0.099). The difference in the mean values among the different levels of REP is greater than would be expected by chance after allowing for effects of differences in TRT. There is a statistically significant difference (P = 0.006). To isolate which group(s) differ from the others use a multiple comparison procedure. Power of performed test with alpha = 0.0500: for TRT : 0.335 Power of performed test with alpha = 0.0500: for REP : 0.911 Least square means for TRT : Group Mean CoversoiI 0.150 Cvr/Pitting .0433 Cvr/Sl.B. 0.0867 Cvr/AM inoc. 0.0767 Control 0.210 Std Err of LS Mean = 0.0396 Least square means for REP : Group Mean 1.000 0.0440 2.000 0.0680 3.000 0.228 Std Err of LS Mean = 0.0306 102 Table 61. Two way analysis of variance of sediment yield, 2000 continued. S tatistical A n alysis R esults con tin u ed All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Diff of Means p Control vs. CvrZPitting 0.167 5 Control vs. CvrZAM inoc. 0.133 4 Control vs. Cvr/Sl.B. 0.123 3 Control vs. Coversoil 0.0600 2 Coversoil vs. CvrZPitting 0.107 4 Coversoil vs. Cvr/AM inoc. 0.0733 3 Coversoil vs. CvrZSl.B. 0.0633 2 CvrZSl.B. vs. CvrZPitting 0.0433 3 Cvr/Sl.B. vs. Cvr/AM inoc. 0.01000 2 Cvr/AM inoc. vs. Cvr/Pitting 0.0333 2 Comparisons for factor: REP Comparison Diff of Means 3.000 vs. 1.000 0.184 3.000 vs. 2.000 0.160 2.000 vs. 1.000 0.0240 p 3 2 2 q q 4.214 3.371 3.118 1.517 2.697 1.854 1.601 1.096 0.253 0.843 P 6.006 0.007 5.222 0.006 0.783 0.595 P 0.096 0.158 0.130 0.315 0.298 0.429 0.290 0.728 0.863 0.568 P 0.050 No Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test P0.050 Yes Yes No A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 103 Table 62. Two way analysis of variance of sediment yield, 2001. S tatistical A n alysis R esults______ General Linear Model (No Interactions) Dependent Variable: 2001 Total Sediment Yield (Mg/ha) Normality Test: Passed (P = 0.022) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 4.275 0.0385 11.062 15.375 MS 1.069 0.0192 1.383 1.098 F 0.773 0.0139 P 0.572 0.986 The difference in the mean values among the different levels of TRT is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REP. There is not a statistically significant difference (P = 0.572). The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.986). Power of performed test with alpha = 0.0500: for TRT : 0.0502 Power of performed test with alpha = 0.0500: for REP : 0.0500 Least square means for TRT : Group Mean Coversoil 1.680 Cvr/Pitting 0.210 Cvr/Sl.B. 1.010 Cvr/AM inoc. 1.603 Control 1.343 Std Err of LS Mean = 0.679 Least square means for REP : Group Mean 1.000 1.106 2.000 1.230 3.000 1.172 Std Err of LS Mean = 0.526 104 Table 63. Two way analysis of variance of rill severity class, 2000. S tatistical A n alysis R esults______________ General Linear Model (No Interactions) Dependent Variable: 2000 Rill Severity Class (rank transformed) Normality Test: Passed (P = 0.018) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 16.000 120.000 32.000 168.000 MS 4.000 60.000 4.000 12.000 F 1.000 15.000 P 0.461 0.002 The difference in the mean values among the different levels of TRT is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REP. There is not a statistically significant difference (P = 0.461). The difference in the mean values among the different levels of REP is greater than would be expected by chance after allowing for effects of differences in TRT. There is a statistically significant difference (P = 0.002). To isolate which group(s) differ from the others use a multiple comparison procedure. Power of performed test with alpha = 0.0500: for TRT : 0.0502 Power of performed test with alpha = 0.0500: for REP : 0.980 Least square means for TRT : Group Mean Coversoil 9.000 Cvr/Pitting 6.000 Cvr/Sl.B. 8.333 Cvr/AM inoc. 8.333 Control 8.333 Std Err of LS Mean = 1.155 Least square means for REP : Group Mean 1.000 6.000 2.000 6.000 3.000 12.000 Std Err of LS Mean = 0.894 105 Table 63. Two way analysis of variance of rill severity class, 2000 continued. S tatistical A nalysis R esults con tin u ed All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Diff of Means p Coversoil vs. CvrZPitting 3.000 5 Coversoil vs. Cvr/AM inoc. 0.667 4 Coversoil vs. Cvr/Sl.B. 0.667 3 Coversoil vs. Control 0.667 2 Control vs. Cvr/Pitting 2.333 4 Control vs. AM inoc. 1.776E-015 3 Control vs. Cvr/Sl.B. 1.776E-015 2 Cvr/Sl.B. vs. Cvr/Pitting 2.333 3 Cvr/Sl.B. vs. AM inoc. 0.000 2 Cvr/AM inoc. vs. Cvr/Pitting 2.333 2 Comparisons for factor: REP Comparison DifF of Means p 3.000 vs. 2.000 6.000 3 3.000 vs. 1.000 6.000 2 1.000 vs. 2.000 0.000 2 q q 2.598 0.577 0.577 0.577 2.021 1.538E-015 1.538E-015 2.021 0.000 2.021 P 6.708 0.004 6.708 0.002 0.000 1.000 P 0.417 0.976 0.913 0.694 0.518 1.000 1.000 0.372 1.000 0.191 P0.050 No Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test Do Not Test P<0.050 Yes Yes No A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 106 Table 64. Two way analysis of variance of rill severity class, 2001. S tatistical A nalysis R esults______ General Linear Model (No Interactions) Dependent Variable: 2001 Rill Severity Class Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 5.204 0.124 1.876 7.204 MS 1.301 0.0620 0.234 0.515 F 5.548 0.264 P 0.019 0.774 The difference in the mean values among the different levels of TRT is greater than would be expected by chance after allowing for effects of differences in REP. There is a statistically significant difference (P = 0.019). To isolate which group(s) differ from the others use a multiple comparison procedure. The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.774). Power of performed test with alpha = 0.0500: for TRT : 0.729 Power of performed test with alpha = 0.0500: for REP : 0.0500 Least square means for TRT : Group Mean Coversoil 3.000 Cvr/Pitting 1.500 Cvr/Sl.B. 2.467 Cvr/AM inoc. 2.767 Control 3.167 Std Err of LS Mean = 0.280 Least square means for REP Group Mean 1.000 2.460 2.000 2.680 3.000 2.600 Std Err of LS Mean = 0.217 107 Table 64. Two way analysis of variance of rill severity class, 2001 continued. S tatistical A n alysis R esults continued_________________________________ All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Diff of Means p Control vs. Cvr/Pitting 1.667 5 Control vs. Cvr/Sl.B. 0.700 4 Control vs. Cvr/AM inoc. 0.400 3 Control vs. Coversoil 0.167 2 Coversoil vs. Cvr/Pitting 1.500 4 Coversoil vs. Cvr/Sl.B. 0.533 3 Coversoil vs. Cvr/AM inoc. 0.233 2 Cvr/AM inoc. vs. Cvr/Pitting 1.267 3 Cvr/AM inoc.vs. Cvr/Sl.B. 0.300 2 Cvr/Sl.B. vs. Cvr/Pitting 0.967 2 Comparisons for factor: REP Comparison Diff of Means 2.000 vs. 1.000 0.220 2.000 vs. 3.000 0.0800 3.000 vs. 1.000 0.140 P 3 2 2 q q 5.961 2.504 1.431 0.596 5.365 1.908 0.835 4.531 1.073 3.458 P 1.016 0.760 0.369 0.801 0.646 0.660 P 0.018 0.352 0.591 0.685 0.022 0.410 0.572 0.030 0.470 0.040 P 0.050 Yes No Do Not Test Do Not Test Yes Do Not Test Do Not Test Yes Do Not Test Yes P0.050 No Do Not Test Do Not Test A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 108 Table 65. Linear regression of mean rill severity class on total annual sediment yield, _________ 2000._______________________________________________________ S tatistical A nalysis R esults_________________________________ 2000 LOG Sediment Yield = -4.876 + (3.606 * 2000 Mean Rill Severity Class) N = 15.000 R = 0.756 Rsqr = 0.571 Adj Rsqr = 0.538 Standard Error of Estimate = 0.269 Constant Mean Rill Severity Coefficient -4.876 3.606 Std. Error 0.904 0.867 t -5.394 4.161 P <0.001 0.001 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 1.248 0.937 2.186 MS 1.248 0.0721 0.156 F 17.312 P 0.001 Normality Test: Passed (P = 0.452) Constant Variance Test: Passed (P = 0.944) Power of performed test with alpha = 0.050: 0.927 109 Table 66. Linear regression of mean rill severity class on total annual sediment yield, 2001.____________________________________________________________ _______________ S tatistical A n alysis R esults________ 2001 LOG Sediment Yield — 1.732 + (0.615 * 2001 Mean Rill Severity Class) N = 15.000 R = 0.871 Rsqr = 0.758 Adj Rsqr = 0.740 Standard Error of Estimate = 0.259 Constant Mean Rill Severity Coefficient -1.732 0.615 Std. Error 0.257 0.0964 t -6.730 6.383 P <0.001 <0.001 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 2.726 0.870 3.595 MS 2.726 0.0669 0.257 F 40.749 P <0.001 Normality Test: Passed (P = 0.326) Constant Variance Test: Passed (P = 0.050) Power of performed test with alpha = 0.050: 0.996 no Table 67. Linear regression of total precipitation on total annual sediment yield, 2000. S tatistical A n alysis R esults Data source: 2000 Sediment Yield to Total Precipitation SedimentYield 2000 = 0.0120 + (0.0235 * Total Precipitation) N =3.000 R = 0.966 Rsqr = 0.934 Adj Rsqr = 0.868 Standard Error of Estimate = 0.010 Coefficient 0.0120 0.0235 Constant Total Precipitation Analysis of Variance: DF Regression I Residual I Total 2 SS 0.00156 0.000110 0.00167 Std. Error 0.00893 0.00626 MS 0.00156 0.000110 0.000833 Normality Test: Passed (P = 0.383) Constant Variance Test: Failed (P = <0.001) F 14.119 t 1.349 3.758 P 0.406 0.166 P 0.166 Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. Ill Table 68. Linear regression of maximum daily precipitation on total annual sediment ________ yield, 2000. __________________________________________ S tatistical A n alysis R esults_____________ Data source: 2000 Sediment Yield and Maximum Daily Precipitation Sediment Yield 2000 = 0.0174 + (0.0224 * Maximum Daily Precipitation) N =3.000 R = 0.998 Rsqr = 0.996 Adj Rsqr = 0.992 Standard Error of Estimate = 0.003 Constant Max. Daily Precip. Coefficient 0.0174 0.0224 Std. Error 0.00190 0.00140 t 9.148 16.021 P 0.069 0.040 Analysis of Variance: DF Regression I Residual I Total 2 SS 0.00166 0.00000647 0.00167 MS 0.00166 0.00000647 0.000833 F 256.688 P 0.040 Normality Test: Passed (P = 0.504) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. 112 Table 69. Linear regression of maximum hourly precipitation on total annual sediment ________ yield, 2000.____________________ ______________________________ S tatistical A n alysis R esults_________ __________________________ Data source: Sediment Yield 2000 to Maximum Hourly Precipitation Sediment Yield 2000 = 0.0179 + (0.0301 * Maximum Hourly Precipitation) N =3.000 R = 1.000 Rsqr = 0.999 Adj Rsqr = 0.998 Standard Error of Estimate = 0.001 Constant Max. Hrly. Precip. Coefficient 0.0179 0.0301 Std. Error 0.000943 0.000942 t 19.000 31.947 P 0.033 0.020 Analysis of Variance: DF Regression I Residual I Total 2 SS 0.00167 0.00000163 0.00167 MS 0.00167 0.00000163 0.000833 F 1020.593 P 0.020 Normality Test: Passed (P = 0.518) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. 113 Table 70. Linear regression of total precipitation on total annual sediment yield, 2001. S tatistical A n alysis R esults___________ Sediment Yield 2001 = 0.932 - (0.200 * Total Precipitation) N = 3.000 R = 0.786 Rsqr = 0.617 Adj Rsqr = 0.234 Standard Error of Estimate = 0.346 Constant Tot. Precip. Coefficient 0.932 -0.200 Analysis of Variance: DF Regression I Residual I Total 2 Std. Error 0.471 0.158 t 1.978 -1.270 P 0.298 0.425 SS MS F P 0.193 0.193 1.612 0.425 0.120 0.120 0.312 0.156 Normality Test: Passed (P = 0.447) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. 114 Table 71. Linear regression of maximum daily precipitation on total annual sediment ________ yield, 2001.______________ S tatistical A nalysis R esults______________________________________ Sediment Yield 2001 = 0.989 - (0.498 * Maximum Daily Precipitation) N =3.000 R = 0.907 Rsqr = 0.823 Adj Rsqr = 0.646 Standard Error of Estimate = 0.235 Coefficient Constant 0.989 Max. Daily Precip. -0.498 Analysis of Variance: DF Regression I Residual I Total 2 SS 0.257 0.0553 0.312 Std. Error 0.309 0.231 t 3.199 -2.156 P 0.193 0.276 MS 0.257 0.0553 0.156 F 4.650 P 0.276 Normality Test: Passed (P = 0.478) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. 115 Table 72. Linear regression of maximum hourly precipitation on total annual sediment _________ yield, 2001.___________________________________________________ S tatistical A nalysis R esults________________________________________________ Sediment Yield 2001 = 1.325 - (1.410 * Maximum Hourly Precipitation) N =3.000 R = 0.975 Rsqr = 0.951 Adj Rsqr = 0.902 Standard Error of Estimate = 0.124 Coefficient Constant 1.325 Max. Hourly Precip. -1.410 Std. Error 0.224 0.321 t 5.907 -4.398 P 0.107 0.142 Analysis of Variance: DF Regression I Residual I Total 2 MS 0.297 0.0153 0.156 F 19.343 P 0.142 SS 0.297 0.0153 0.312 Normality Test: Passed (P = 0.370) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: <0.001 The power of the performed test (<0.001) is below the desired power of 0.800. You should interpret the negative findings cautiously. 116 Table 73. Two way analysis of variance of percent rock cover during 2001. S tatistical A n alysis R esults__________ General Linear Model (No Interactions) Dependent Variable: Percent Rock Cover Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 1.000) Source of Variation trt rep Residual Total DF 4 2 8 14 SS 831.204 87.481 753.732 1672.417 MS 207.801 43.741 94.216 119.458 F 2.206 0.464 P 0.158 0.645 The difference in the mean values among the different levels of trt is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in rep. There is not a statistically significant difference (P = 0.158). The difference in the mean values among the different levels of rep is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in trt. There is not a statistically significant difference (P = 0.645). Power of performed test with alpha = 0.0500: for t r t : 0.229 Power of performed test with alpha = 0.0500: for rep :0.0500 Least square means for tr t: Group Coversoil Coversoil/Pitting Coversoil/Slash Barriers Coversoil/AM Inoculum Control Std Err of LS Mean = 5.604 Least square means for rep : Group Mean 1.000 47.400 2.000 42.380 3.000 42.180 Std Err of LS Mean = 4.341 Mean 35.667 44.667 39.967 4 1.967 57.667 117 Table 74. Linear regression of percent rock cover on sediment yield, 2001. S tatistical A n alysis R esults 2001 Sediment Yield (Mg/ha) —0.937 + (0.00528 * percent rock cover) N = 15.000 R = 0.0552 Rsqr = 0.00305 Adj Rsqr = 0.000 Standard Error of Estimate = 1.084 Constant % rock cover Coefficient 0.937 0.00528 Std. Error 1.199 0.0265 t 0.781 0.199 P 0.449 0.845 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.0467 15.284 15.331 MS 0.0467 1.176 1.095 F 0.0397 P 0.845 Normality Test: Passed (P = 0.260) Constant Variance Test: Passed (P = 0.154) Power of performed test with alpha = 0.050: 0.038 The power of the performed test (0.038) is below the desired power of 0.800. You should interpret the negative findings cautiously. 118 Table 75. Linear regression of percent rock cover on biomass, 2001. S tatistical A n alysis R esults______________________________________ Biomass 2001 = 356.054 —(4.930 * percent rock cover) N = 15.000 R = 0.680 Rsqr = 0.463 Adj Rsqr = 0.422 Standard Error of Estimate = 60.208 Coefficient Constant 356.054 % rock cover -4.930 Analysis of Variance: DF Regression I Residual 13 Total 14 Std. Error 66.600 1.472 SS 40640.428 47125.596 87766.024 t 5.346 -3.348 MS 40640.428 3625.046 6269.002 Normality Test: Passed (P = 0.637) Constant Variance Test: Passed (P = 0.657) Power of performed test with alpha = 0.050: 0.820 P <0.001 0.005 F 11.211 P 0.005 119 Table 76. Linear regression of percent rock cover on total annual runoff, 2001. S tatistical A nalysis R esults____________________ 2001 Total Annual Runoff = 4.326 + (2.682 * percent rock cover) N = 15.000 R = 0.408 Rsqr = 0.167 Adj Rsqr = 0.103 Standard Error of Estimate = 67.992 Coefficient Constant 4.326 % rock cover 2.682 Analysis of Variance: DF Regression I Residual 13 Total 14 Std. Error 75.210 1.663 SS 12032.885 60098.433 72131.318 t 0.0575 1.613 MS 12032.885 4622.956 5152.237 Normality Test: Passed (P = 0.080) Constant Variance Test: Passed (P = 0.863) P 0.955 0.131 F P 2.603 0.131 Power of performed test with alpha = 0.050: 0.324 The power of the performed test (0.324) is below the desired power of 0.800. You should interpret the negative findings cautiously. 120 Table 77. Linear regression of percent rock cover on rill severity class, 2001. S tatistical A n alysis R esults______________________________________________ Rill Class Severity = 1.907 + (0.0153 * % rock cover) N = 15.000 R = 0.233 Rsqr = 0.0543 Adj Rsqr = 0.000 Standard Error of Estimate = 0.724 Constant MEAN Coefficient 1.907 0.0153 Analysis of Variance: DF Regression I Residual 13 Total 14 Std. Error 0.801 0.0177 P t 2.382 0.033 0.864 0.403 SS MS F P 0.391 0.391 0.746 0.403 6.813 0.524 7.204 0.515 Normality Test: Passed (P = 0.469) Constant Variance Test: Passed (P = 0.773) Power of performed test with alpha = 0.050: 0.128 The power of the performed test (0.128) is below the desired power of 0.800. You should interpret the negative findings cautiously. 121 Table 78. Two way analysis of variance of runoff (mVha), 2000. S tatistical A n alysis R esults_______ General Linear Model (No Interactions) Dependent Variable: 2000 Total Annual Runoff (m3/ha) Normality Test: Passed (P = 0.093) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 1913.657 854.137 2875.583 5643.377 MS 478.414 427.069 359.448 403.098 F P 1.331 0.338 1.188 0.353 The difference in the mean values among the different levels of TRT is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REP. There is not a statistically significant difference (P = 0.338). The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.353). Power of performed test with alpha = 0.0500: for TRT : 0.0927 Power of performed test with alpha = 0.0500: for REP : 0.0696 Least square means for TRT : Group Mean Coversoil 49.167 Coversoil/Pitting 39.733 Coversoil/Slash Barriers 45.300 Coversoil/AM inoculm 43.200 Control 71.533 Std Err of LS Mean = 10.946 Least square means for REP Group 1.000 2.000 3.000 Std Err of LS Mean = 8.479 : Mean 60.240 46.420 42.700 122 Table 79. Two way analysis of variance of runoff (nrVha), 2001. S tatistical A n alysis R esults _________________________________ General Linear Model (No Interactions) Dependent Variable: 2001Total Annual Runoff (m3/ha) Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 30451.777 4305.241 37386.959 72143.977 MS 7612.944 2152.621 4673.370 5153.141 F P 1.629 0.258 0.461 0.647 The difference in the mean values among the different levels of TRT is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REP. There is not a statistically significant difference (P = 0.258). The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.647). Power of performed test with alpha = 0.0500: for TRT : 0.136 Power of performed test with alpha = 0.0500: for REP : 0.0500 Least square means for TRT : Group Mean Coversoil 123.533 Coversoil/Pitting 66.000 Coversoil/Slash Barriers 119.567 CoversoiEAM inoculum 99.767 Control 202.700 Std Err of LS Mean = 39.469 Least square means for REP : Group Mean 1.000 133.840 2.000 98.360 3.000 134.740 Std Err of LS Mean = 30.572 123 Table 80. Linear regression of runoff on sediment yield, 2000. S tatistical A n alysis R esults________________________________ log I (!(Sediment Yield 2000) = -1.165 + (0.000789 * 2000 Runoff) N = 15.000 R = 0.0401 Rsqr = 0.00161 Adj Rsqr = 0.000 Standard Error of Estimate = 0.410 Coefficient Constant -1.165 2000 Runoff 0.000789 Analysis of Variance: DF Regression I Residual 13 Total 14 Std. Error 0.291 0.00545 SS 0.00351 2.182 2.186 t P -3.999 0.002 0.145 0.887 MS 0.00351 0.168 0.156 Normality Test: Passed (P = 0.138) Constant Variance Test: Passed (P = 0.388) F 0.0209 P 0.887 Power of performed test with alpha = 0.050: 0.034 The power of the performed test (0.034) is below the desired power of 0.800. You should interpret the negative findings cautiously. 124 Table 81. Linear regression of runoff on sediment yield, 2001. S tatistical A nalysis R esults_________________ 2001 Sediment Yield = 1.216 - (0.000382 * 2001 Runoff) N = 15.000 R = 0.0262 Rsqr = 0.000684 Adj Rsqr = 0.000 Standard Error of Estimate = 1.087 Coefficient Constant 1.216 2001 Runoff -0.000382 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.0105 15.365 15.375 Std. Error 0.569 0.00405 t 2.137 -0.0943 MS 0.0105 1.182 1.098 Normality Test: Passed (P = 0.157) Constant Variance Test: Passed (P = 0.176) P 0.052 0.926 F 0.00890 P 0.926 Power of performed test with alpha = 0.050: 0.031 The power of the performed test (0.031) is below the desired power of 0.800. You should interpret the negative findings cautiously. 125 Table 82. Linear regression of runoff on mean rill severity class, 2000. S tatistical A nalysis R esults________________________________________ Mean Rill Severity Class = 0.869 + (0.00000355 * 2000 Runoff) N = 15.000 R = 0.833 Rsqr = 0.694 Adj Rsqr = 0.670 Standard Error of Estimate = 0.048 Constant 2000 Runoff Coefficient 0.869 0.00000355 Analysis of Variance: DF SS Regression I 0.0666 Residual 13 0.0294 Total 14 0.0960 Normality Test: Std. Error t 0.0338 25.699 0.000000654 5.425 P <0.001 <0.001 MS 0.0666 0.00226 0.00686 P <0.001 Passed (P = 0.069) Constant Variance Test: Failed (P = <0.001) Power of performed test with alpha = 0.050: 0.986 F 29.430 126 Table 83. Linear regression of runoff to mean rill severity class, 2001 S tatistical A n alysis R esults 2001 Mean Rill Severity Class = 2.733 - (0.0000000359 * 2001 Runoff) N = 15.000 R = 0.214 Rsqr = 0.0457 Adj Rsqr = 0.000 Standard Error of Estimate = 0.723 Coefficient Constant 2.733 2001 Runoff -0.0000000359 Std. Error 0.274 0.0000000456 Analysis of Variance: DF Regression I Residual 13 Total 14 MS 0.325 0.523 0.508 SS 0.325 6.793 7.119 t 9.983 -0.789 F 0.623 P <0.001 0.444 P 0.444 Normality Test: Passed (P = 0.314) Constant Variance Test: Passed (P = 0.287) Power of performed test with alpha = 0.050: 0.114 The power of the performed test (0.114) is below the desired power of 0.800. You should interpret the negative findings cautiously. 127 Table 84. Two way analysis of variance on biomass (kg/ha), 2001. S tatistical A nalysis R esults_____________ General Linear Model (No Interactions) Dependent Variable: 2001 Biomass (kg/ha) Normality Test: Passed (P = 0.079) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 66363.951 1443.316 19958.757 87766.024 MS 16590.988 721.658 2494.845 6269.002 F P 6.650 0.012 0.289 0.756 The difference in the mean values among the different levels of TRT is greater than would be expected by chance after allowing for effects of differences in REP. There is a statistically significant difference (P = 0.012). To isolate which group(s) differ from the others use a multiple comparison procedure. The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.756). Power of performed test with alpha = 0.0500: for TRT : 0.826 Power of performed test with alpha = 0.0500: for REP : 0.0500 Least square means for TRT : Group Mean Coversoil 185.467 Cvr/Pitting 128.967 Cvr/SIB 224.633 Cvr/AM inoc. 129.567 Control 27.467 Std Err of LS Mean = 28.838 Least square means for REP : Group Mean 1.000 126.280 2.000 150.020 3.000 141.360 Std Err of LS Mean = 22.338 128 Table 84. Two way analysis of variance on biomass (kg/ha), 2001 continued. S tatistical A n alysis R esults con tin u ed All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Cvr/SIBvs. Control Cvr/SIBvs. Cvr/Pitting Cvr/SIBvs. Cvr/AM inoc. Cvr/SIBvs. Coversoil Coversoil vs. Control Coversoil vs. Cvr/Pitting Coversoil vs. Cvr/AM inoc. Cvr/AM inoc. . vs. Control Cvr/AM inoc. vs. Cvr/Pitting Cvr/Pitting vs. Control Difif of Means p 197.167 5 95.667 4 95.067 3 39.167 2 158.000 4 56.500 3 55.900 2 102.100 3 0.600 2 101.500 2 Comparisons for factor: REP Comparison Diff of Means 2.000 vs. 1.000 23.740 2.000 vs. 3.000 8.660 3.000 vs. 1.000 15.080 p 3 2 2 q 1.063 0.388 0.675 P q 6.837 0.008 3.317 0.166 3.297 0.108 1.358 0.365 5.479 0.020 1.959 0.392 1.938 0.208 3.541 0.084 0.0208 0.989 3.520 0.038 P O .050 Yes No Do Not Test Do Not Test Yes Do Not Test Do Not Test No Do Not Test Do Not Test P 0.741 0.791 0.646 P<0.050 No Do Not Test Do Not Test A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 129 Table 85. Two way analysis of variance on percent canopy cover, 2001. S tatistical A n alysis R esults________________________ General Linear Model (No Interactions) Dependent Variable: 2001 Percent Canopy Cover Normality Test: Passed (P = 0.061) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 202.400 14.800 39.200 256.400 MS 50.600 7.400 4.900 18.314 F 10.327 1.510 P 0.003 0.278 The difference in the mean values among the different levels of TRT is greater than would be expected by chance after allowing for effects of differences in REP. There is a statistically significant difference (P = 0.003). To isolate which group(s) differ from the others use a multiple comparison procedure. The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.278). Power of performed test with alpha = 0.0500: for TRT : 0.968 Power of performed test with alpha = 0.0500: for REP : 0.106 Least square means for TRT : Group Mean Coversoil 16.000 Cvr/Pitting 14.667 slash 17.000 Cvr/AM inoc. 14.667 Control 6.667 Std Err of LS Mean = 1.278 130 Table 85. Two way analysis of variance on percent canopy cover, 2001 continued. S tatistical A n alysis R esults con tin u ed Least square means for REP : Group Mean 1.000 14.400 2.000 14.600 3.000 12.400 Std Err of LS Mean = 0.990 All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Diff of Means p Cvr/SIB vs. Control 10.333 5 Cvr/SIB vs. Cvr/AM inoc. 2.333 4 Cvr/SIB vs. Cvr/Pitting 2.333 3 Cvr/SIB vs. Coversoil 1.000 2 Coversoil vs. Control 9.333 4 Coversoil vs. Cvr/AM inoc. 1.333 3 Coversoil vs. Cvr/Pitting 1.333 2 Cvr/Pitting vs. Control 8.000 3 Cvr/Pitting vs. Cvr/AM inoc. 0.000 2 Cvr/AM inoc. vs. Control 8.000 2 q 8.085 1.826 1.826 0.782 7.303 1.043 1.043 6.260 0.000 6.260 P 0.003 0.593 0.439 0.595 0.004 0.749 0.482 0.006 1.000 0.002 Comparisons for factor: REP Comparison Diff of Means 2.000 vs. 3.000 2.200 2.000 vs. 1.000 0.200 1.000 vs. 3.000 2.000 P 0.311 0.890 0.191 P<0.050 No Do Not Test Do Not Test p 3 2 2 q 2.222 0.202 2.020 P<0.050 Yes No Do Not Test Do Not Test Yes Do Not Test Do Not Test Yes Do Not Test Yes A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 131 Table 86. Two way analysis of variance on percent basal cover, 2001. S tatistical A n alysis R esults______________________ General Linear Model (No Interactions) Dependent Variable: % Basal Cover Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 1.000) Source of Variation TRT REP Residual Total DF 4 2 8 14 SS 46.649 2.505 19.715 68.869 MS 11.662 1.253 2.464 4.919 F 4.732 0.508 P 0.030 0.620 The difference in the mean values among the different levels of TRT is greater than would be expected by chance after allowing for effects of differences in REP. There is a statistically significant difference (P = 0.030). To isolate which group(s) differ from the others use a multiple comparison procedure. The difference in the mean values among the different levels of REP is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in TRT. There is not a statistically significant difference (P = 0.620). Power of performed test with alpha = 0.0500: for TRT : 0.633 Power of performed test with alpha = 0.0500: for REP : 0.0500 Least square means for TRT Group Coversoil Coversoil/Pitting Coversoil/Slash Barrier Coversoil/AM inoculum Control Std Err of LS Mean = 0.906 : Least square means for REP : Group Mean 1.000 4.820 2.000 3.820 3.000 4.280 Std Err of LS Mean = 0.702 Mean 6.033 4.133 5.367 5.000 1.000 132 Table 86. Two way analysis of variance on percent basal cover, 2001 continuedsta tistic a l A nalysis R esults All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: TRT Comparison Diff of Means p Coversoil vs. Control 5.033 5 Coversoil vs. Cvr/Pitting 1.900 4 Coversoil vs. Cvr/AM inoc. 1.033 3 Coversoil vs. Cvr/Sl.B 0.667 2 Cvr/Sl.B.vs. Control 4.367 4 Cvr/Sl.B.vs. Cvr/Pitting 1.233 3 Cvr/Sl.B.vs. Cvr/AM inoc. 0.367 2 Cvr/AM inoc. vs. Control 4.000 3 Cvr/AM inoc. vs. Cvr/Pitting 0.867 2 Cvr/Pitting vs. Control 3.133 2 Comparisons for factor: REP Comparison Diff of Means 1.000 vs. 2.000 1.000 1.000 vs. 3.000 0.540 3.000 vs. 2.000 0.460 P 3 2 2 q P 5.553 2.096 1.140 0.736 4.818 1.361 0.405 4.413 0.956 3.457 0.027 0.489 0.710 0.617 0.038 0.619 0.782 0.034 0.518 0.040 P<0.050 Yes No Do Not Test Do Not Test Yes Do Not Test Do Not Test Yes Do Not Test Yes q P P 0.050 1.424 0.593 No 0.769 0.602 Do Not Test 0.655 0.656 Do Not Test A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. 133 Table 87. Linear regression of biomass (kg/ha) on sediment yield, 2001. S tatistical A nalysis R esults__________________ 2001 Sediment Yield (Mg/ha) = 0.629 + (0.00388 * 2001 Biomass (kg/ha)) N = 15.000 R = 0.294 Rsqr = 0.0864 Adj Rsqr = 0.0161 Standard Error of Estimate = 1.038 Constant Biomass (kg/ha) Coefficient 0.629 0.00388 Std. Error 0.557 0.00350 t 1.130 1.109 P 0.279 0.288 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 1.324 14.006 15.331 MS 1.324 1.077 1.095 F 1.229 P 0.288 Normality Test: Passed (P = 0.316) Constant Variance Test: Passed (P = 0.046) Power of performed test with alpha = 0.050: 0.181 The power of the performed test (0.181) is below the desired power of 0.800. You should interpret the negative findings cautiously. 134 Table 88. Linear regression of percent canopy cover on sediment yield, 2001. S tatistical A nalysis R esults_________________ 2001 Sediment Yield (Mg/ha) = 1.186 - (0.00121 * percent canopy cover) N = 15.000 R = 0.00497 Rsqr = 0.0000247 Adj Rsqr = 0.000 Standard Error of Estimate = 1.086 Constant % canopy cover Coefficient 1.186 -0.00121 Std. Error 0.977 0.0678 t 1.214 -0.0179 P 0.246 0.986 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.000378 15.330 15.331 MS 0.000378 1.179 1.095 F 0.000321 P 0.986 Normality Test: Passed (P = 0.198) Constant Variance Test: Passed (P = 0.052) Power of performed test with alpha = 0.050: 0.026 The power of the performed test (0.026) is below the desired power of 0.800. You should interpret the negative findings cautiously. 135 Table 89. Linear regression of percent basal cover on sediment yield, 2001. S tatistical A nalysis R esults_____________________ 2001 Sediment Yield (Mg/ha) = 1.635 - (0.108 * % basal cover) N = 15.000 R = 0.229 Rsqr = 0.0524 Adj Rsqr = 0.000 Standard Error of Estimate = 1.057 Coefficient Constant 1.635 %basal cover -0.108 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.804 14.527 15.331 Std. Error 0.613 0.127 t 2.668 -0.848 MS 0.804 1.117 1.095 Normality Test: Passed (P = 0.018) Constant Variance Test: Passed (P = 0.753) P 0.019 0.412 F 0.719 P 0.412 Power of performed test with alpha = 0.050: 0.125 The power of the performed test (0.125) is below the desired power of 0.800. You should interpret the negative findings cautiously. 136 Table 90. Linear regression of biomass (kg/ha) on runoff, 2001. S tatistical A nalysis R esults____________________________________ 2001 Runoff(m3/ha) = 176.081 - (0.386 * 2001 Biomass (kg/ha) N = 15.000 R = 0.426 Rsqr = 0.181 Adj Rsqr = 0.118 Standard Error of Estimate = 67.399 Constant OlPROD Coefficient Std. Error 176.081 36.139 -0.386 0.228 -1.698 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 13090.577 59053.400 72143.977 t 4.872 0.113 MS 13090.577 4542.569 5153.141 Normality Test: Passed (P = 0.399) Constant Variance Test: Passed (P = 0.566) P <0.001 F P 2.882 0.113 Power of performed test with alpha = 0.050: 0.351 The power of the performed test (0.351) is below the desired power of 0.800. You should interpret the negative findings cautiously. 137 Table 91. Linear regression of percent canopy cover on runoff, 2001. S tatistical A n alysis R esults_______________________________________ 2001 Runoff = 217.996 - (6.934 * Percent Canopy Cover) N = 15.000 R = 0.413 Rsqr = 0.171 Adj Rsqr = 0.107 Standard Error of Estimate = 67.833 Constant % Canopy Coefficient 217.996 -6.934 4.236 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 12326.172 59817.805 72143.977 Std. Error 61.028 -1.637 t 3.572 0.126 MS 12326.172 4601.370 5153.141 F P 2.679 0.126 Normality Test: Passed (P = 0.071) Constant Variance Test: Passed (P = 0.985) P 0.003 Power of performed test with alpha = 0.050: 0.331 The power of the performed test (0.331) is below the desired power of 0.800. You should interpret the negative findings cautiously. 138 Table 92. Linear regression of percent basal cover on runoff, 2001. S tatistical A nalysis R esults______ 2001 Runoff —173.771 - (11.948 * Percent Basal Cover) N = 15.000 R = 0.369 Rsqr = 0.136 Adj Rsqr = 0.0698 Standard Error of Estimate = 69.233 Coefficient Constant 173.771 %basal cover -11.948 Std. Error 40.130 8.343 Analysis of Variance: DF SS Regression I 9832.151 Residual 13 62311.826 Total 14 72143.977 t 4.330 -1.432 MS 9832.151 4793.217 5153.141 Normality Test: Passed (P = 0.197) Constant Variance Test: Passed (P = 0.359) P <0.001 0.176 F P 2.051 0.176 Power of performed test with alpha = 0.050: 0.268 The power of the performed test (0.268) is below the desired power of 0.800. You should interpret the negative findings cautiously. 139 Table 93. Linear regression of biomass (kg/ha) on rill severity, 2001. S tatistical A nalysis R esults___________________ 2001 Mean Rill Severity Class = 2.601 - (0.000152 * 2001 Biomass (kg/ha) N = 15.000 R = 0.0168 Rsqr = 0.000281 Adj Rsqr = 0.000 Standard Error of Estimate = 0.744 Coefficient Std. Error t P Constant 2.601 0.399 6.518 <0.001 2001 Biomass -0.000152 0.00251 -0.0605 0.953 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.00203 7.202 7.204 MS 0.00203 0.554 0.515 Normality Test: Passed (P = 0.200) Constant Variance Test: Passed (P = 0.913) F 0.00366 P 0.953 Power of performed test with alpha = 0.050: 0.029 The power of the performed test (0.029) is below the desired power of 0.800. You should interpret the negative findings cautiously. 140 Table 94. Linear regression of percent canopy cover on rill severity, 2001. S tatistical A n alysis R esults 2001 Mean Rill Severity Class —3.240 - (0.0478 * 2001 Percent Canopy Cover) N = 15.000 R = 0.285 Rsqr = 0.0814 Adj Rsqr = 0.0107 Standard Error of Estimate = 0.713 Constant % Canopy Cover Coefficient 3.240 -0.0478 Analysis of Variance: DF Regression I Residual 13 Total 14 SS 0.586 6.618 7.204 Std. Error 0.642 0.0446 t 5.047 -1.073 P < 0.001 0.303 MS F P 0.586 1.152 0.303 0.509 0.515 Normality Test: Passed (P = 0.680) Constant Variance Test: Passed (P = 0.695) Power of performed test with alpha = 0.050: 0.173 The power of the performed test (0.173) is below the desired power of 0.800. You should interpret the negative findings cautiously. 141 Table 95. Linear regression of percent basal cover on rill severity, 2001. S tatistical A nalysis R esults___________________________ 2001 Mean Rill Severity Class = 2.946 - (0.0851 * 2001 Percent Basal Cover) N = 15.000 R = 0.263 Rsqr = 0.0692 Adj Rsqr = 0.000 Standard Error of Estimate = 0.718 Coefficient Constant 2.946 %basal cover -0.0851 Analysis of Variance: DF Regression I Residual 13 Total 14 Std. Error 0.416 0.0865 t 7.077 -0.983 P <0.001 0.344 SS MS F P 0.498 0.498 0.966 0.344 6.706 0.516 7.204 0.515 Normality Test: Passed (P = 0.328) Constant Variance Test: Passed (P = 0.120) Power of performed test with alpha = 0.050: 0.152 The power of the performed test (0.152) is below the desired power of 0.800. You should interpret the negative findings cautiously. 142 Table 96. Multiple linear regression of mean rill severity class, runoff, and slope area on ________ sediment yield, 2000. ___________________________________________ S tatistical A n alysis R esults____________________________ 2000 Sediment yield (Mg/ha) = -1.101 + (0.000335 * runoff (m3/ha)) + (1.122 * mean rill severity class) + (0.00115 * slope area (m2)) N = 15.000 R = 0.881 Rsqr = 0.777 Adj Rsqr = 0.716 Standard Error of Estimate = 0.062 Constant runoff (m3/ha) mean rill sev. class slope area (m2) Coefficient -1.101 0.000335 1.122 0.00115 Std. Error 0.230 0.000946 0.209 0.00140 t -4.781 0.354 5.371 0.818 Analysis of Variance: DF Regression 3 Residual 11 Total 14 SS 0.148 0.0426 0.191 MS 0.0493 0.00387 0.0136 F 12.741 Column runoff (m3/ha) mean rill sev. class slope area (m2) SSIncr 0.00217 0.143 0.00259 SSMarg 0.000485 0.112 0.00259 P <0.001 0.730 <0.001 0.431 VIF 1.306 1.227 1.305 P <0.001 The dependent variable 2000 Sediment yield (Mg/ha) can be predicted from a linear combination of the independent variables: P runoff (m3/ha) 0.730 mean rill sev. class <0.001 slope area (m2) 0.431 Not all of the independent variables appear necessary (or the multiple linear model may be underspecified). The following appear to account for the ability to predict 2000 Sediment yield (Mg/ha) (P < 0.05): mean rill severity class Normality Test: Failed (P = 0.001) Constant Variance Test: Passed (P = 0.010) Power of performed test with alpha = 0.050: 0.998 143 Table 97. Multiple linear regression of mean rill severity class, runoff, slope area, ________ biomass, canopy cover, basal cover and rock cover on sediment yield, 2001. S tatistical A n alysis R esults______________ Sediment yield 2001 = -2.950 + (0.164 * mean rill severity class) - (0.00337 * runoff (m3/ha)) + (0.0196 * slope area (m2)) + (0.0156 * biomass (kg/ha)) (0.0635 * canopy cover (%)) - (0.139 * basal cover (%)) + (0.0487 * rock cover (%)) N = 15.000 R = 0.927 Rsqr = 0.859 Adj Rsqr = 0.718 Standard Error of Estimate = 0.556 Coefficient Std. Error t P VIE Constant -2.950 1.571 -1.878 0.102 Mean Rill Sev. Class 0.164 0.659 0.249 0.811 9.977 Runoff (m3/ha) -0.00337 0.00250 -1.349 0.219 1.454 Slope Area (m2) 0.0196 0.0116 1.679 0.137 8.782 Biomass (kg/ha) 0.0156 0.00796 1.962 0.091 17.979 %Canopy Cover -0.0635 0.0979 -0.649 0.537 7.936 % Basal Cover -0.139 0.0916 -1.512 0.174 1.867 % Rock Cover 0.0487 0.0301 1.620 0.149 4.883 Warning: Multicollinearity is present among the independent variables. The variables with the largest values of VIF are causing the problem. Consider getting more data or eliminating one or more variables from the equation. The likely candidates for elimination are: Mean Rill Severity Class, Slope Area, Biomass, % Canopy Cover, % Rock Cover Analysis of Variance: DF Regression 7 Residual 7 Total 14 SS 13.208 2.168 15.375 Column Mean Rill Severity Class Runoff (m /ha) Slope Area (m2) Biomass (kg/ha) % Canopy Cover % Basal Cover % Rock Cover MS F P 1.887 6.093 0.015 0.310 1.098 SSIncr 9.459 1.346 0.144 0.494 0.102 0.850 0.812 SSMarg 0.0192 0.564 0.873 1.192 0.130 0.708 0.812 144 Table 97. Multiple linear regression of mean rill severity class, runoff, slope area, biomass, canopy cover, basal cover and rock cover on sediment yield, 2001 ________ continued.__________________________________________________ S tatistical A nalysis R esults continued___________________ The dependent variable Sediment yield 2001 can be predicted from a linear combination of the independent variables: P Mean Rill Severity Class 0.811 Runoff (m3/ha) 0.219 Slope Area (m2) 0.137 Biomass (kg/ha) 0.091 % Canopy Cover 0.537 % Basal Cover 0.174 % Rock Cover 0.149 Not all of the independent variables appear necessary (or the multiple linear model may be underspecified). The following appear to account for the ability to predict Sediment yield 2001 (P <005): [None] Normality Test: Constant Variance Test: Passed (P = 0.400) Passed (P = 0.050) Power of performed test with alpha = 0.050: 1.000 145 Table 98. Multiple linear regression of mean rill severity class and slope area on runoff, _________ 2000._________________________________________________________ S tatistical A nalysis R esults__________________________________________________________ Runoff 2000 (mVha) = 117.807 - (79.027 * mean rill severity class) + (0.228 * slope area (m ')) N = 15.000 R = 0.486 Rsqr = 0.236 Adj Rsqr = 0.109 Standard Error of Estimate = 18.957 Constant mean rill sev. class slope area (m2) Coefficient 117.807 -79.027 0.228 Std. Error 60.638 59.064 0.138 t 1.943 -1.338 1.656 Analysis of Variance: DF Regression 2 Residual 12 Total 14 SS 1331.619 4312.566 5644.185 MS 665.809 359.380 403.156 F 1.853 Column mean rill sev. class slope area(m2) SSIncr 346.189 985.430 SSMarg 643.359 985.430 P VIF 0.076 0.206 1.057 0.124 1.057 P 0.199 The dependent variable Runoff 2000 (m3/ha) can be predicted from a linear combination of the independent variables: P mean rill sev. class 0.206 slope area (m2) 0.124 Not all of the independent variables appear necessary (or the multiple linear model may be underspecified). The following appear to account for the ability to predict Runoff 2000(m3/ha) (P < 0.05): [ None ] Normality Test: Passed (P = 0.011) Constant Variance Test: Passed (P = 0.014) 146 Table 99. Multiple linear regression of mean rill severity class, slope area, biomass, ________ canopy cover, basal cover and rock cover on runoff, 2001.____________ S tatistical A n alysis R esults____________________________________________________ 2001 Runoff (m3/ha) = 50.774 + (50.929 * Mean Rill Severity Class) - (0.332 * Slope Area (m2)) - (0.677 * Biomass (kg/ha)) + (6.439 * % Canopy Cover) - (5.528 * % Basal Cover) - (0.201 * % Rock Cover) N = 15.000 R = 0.559 Rsqr = 0.312 Adj Rsqr = 0.000 Standard Error of Estimate = 78.750 Coefficient Constant 50.774 Mean Rill Sev. Class 50.929 Slope Area (m2) -0.332 Biomass (kg/ha) -0.677 % Canopy Cover 6.439 % Basal Cover -5.528 % Rock Cover -0.201 Std. Error 221.551 91.473 1.644 1.101 13.666 12.819 4.254 t 0.229 0.557 -0.202 -0.615 0.471 -0.431 -0.0472 P 0.824 0.593 0.845 0.556 0.650 0.678 0.964 VIF 9.605 8.738 17.167 7.722 1.825 4.881 Warning: Multicollinearity is present among the independent variables. The variables with the largest values of VIE are causing the problem. Consider getting more data or eliminating one or more variables from the equation. The likely candidates for elimination are: Mean Rill Severity Class, Slope Area, Biomass, % Canopy Cover, % Rock Cover Analysis of Variance: DF Regression 6 Residual 8 Total 14 SS 22531.146 49612.831 72143.977 Column Mean Rill Severity Class Slope Area (m2) Biomass (kg/ha) % Canopy Cover % Basal Cover % Rock Cover MS 3755.191 6201.604 5153.141 SSIncr 7556.642 2152.658 10758.519 909.196 1140.326 13.805 F P 0.606 0.721 SSMarg 1922.390 253.172 2346.584 1376.501 1153.387 13.805 147 Table 99. Multiple linear regression of mean rill severity class, slope area, biomass, ________ canopy cover, basal cover and rock cover on runoff, 2001 continued. S tatistical A nalysis R esults con tin u ed ______________________________ The dependent variable 2001 Runoff (m3/ha) can be predicted from a linear combination of the independent variables: P Mean Rill Severity Class 0.593 Slope Area (m2) 0.845 Biomass (kg/ha) 0.556 % Canopy Cover 0.650 % Basal Cover 0.678 0.964 % Rock Cover Not all of the independent variables appear necessary (or the multiple linear model may be underspecified). The following appear to account for the ability to predict 2001 Runoff (m3/ha) (P < 0.05): [ None ] Normality Test: Failed (P = 0.007) Constant Variance Test: Passed (P = 0.194) Power of performed test with alpha = 0.050: 0.590 The power of the performed test (0.590) is below the desired power of 0.800. You should interpret the negative findings cautiously. 148 Table 100. Multiple linear regression of maximum hourly precipitation, increase in rill __________ severity class and runoff on sediment yield, 2000 and 2001.____________ S tatistical A nalysis R esults Sediment Yield 2000 and 20001 =0.120 - (1.271 * maximum hourly precipitation (cm)) (0.124 * increase in rill severity class) + (0.0445 * runoff (m3/ha)) N = 6.000 R = 0.995 Rsqr = 0.990 Adj Rsqr 0.975 Standard Error of Estimate = 0.050 Std. Error Coefficient P VIF t Constant 0.120 0.0328 0.067 3.663 Max. Hourly Ppt. (cm)-1.271 0.101 0.006 8.065 -12.583 Inc. Rill Sev. Class -0.124 -4.174 0.0296 0.053 1.938 Runoff (m3/ha) 0.0445 12.448 0.00357 0.006 9.654 Warning: Multicollinearity is present among the independent variables. The variables with the largest values of VIF are causing the problem. Consider getting more data or eliminating one or more variables from the equation. The likely candidates for elimination are: Max. Hourly Ppt., Runoff Analysis of Variance: DF Regression 3 Residual 2 Total 5 Column Max. Hourly Ppt.(cm) Inc. Rill Sev. Class Runoff (rnVha) SS 0.494 0.00506 0.499 SSIncr 0.00878 0.0932 0.392 MS 0.165 0.00253 0.0998 F 65.079 P 0.015 S 0.401 0.0441 0.392 The dependent variable Sediment Yield 2000 and 2001 can be predicted from a linear combination of the independent variables: P Max. Hourly Ppt. (cm) 0.006 Inc. Rill Sev. Class 0.053 Runoff (m3/ha) 0.006 Not all of the independent variables appear necessary (or the multiple linear model may be underspecified). The following appear to account for the ability to predict Sediment Yield 2000 and 2001 (P < 0.05): Max. Hourly Ppt, Runoff Normality Test: Passed (P = 0.216) Constant Variance Test: Passed (P = 0.060) Power of performed test with alpha = 0.050: 0.999______________________________ 149 Table 101. T-test of mean percent AM colonization levels in the coversoil and spoil _________ backfill material during 2000.__________________________________ S tatistical A n alysis R esults_____________________________________________________ t-test Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 0.554) Group Name N Coversoil 9 Control 9 Difference Missing 0 0 Mean 39.444 30.333 Std Dev 8.719 9.513 SEM 2.906 3.171 9.111 t = 2.118 with 16 degrees of freedom. (P = 0.050) 95 percent confidence interval for difference of means: -0.00771 to 18.230 The difference in the mean values of the two groups is not great enough to reject the possibility that the difference is due to random sampling variability. There is not a statistically significant difference between the i nput groups (P = 0.050). Power of performed test with alpha = 0.050: 0.408 The power of the performed test (0.408) is below the desired power of 0.800. You should interpret the negative findings cautiously. 150 Table 102. Two way analysis of variance of percent AM colonization levels in Hordeum __________vulgare, 2001.__________________________________________________ S tatistical A n alysis R esults__________________________________________________________ Two Way Analysis of Variance Data source: % AM colonization levels in barley Balanced Design Dependent Variable: % AM colonization Normality Test: Passed (P = 0.059) Equal Variance Test: Passed (P = 0.337) Source of Variation Treatment REPS Treatment x REPS Residual Total DF 2 2 4 27 35 SS 0.000200 0.00912 0.0705 0.280 0.360 MS 0.000100 0.00456 0.0176 0.0104 0.0103 F 0.00965 0.440 1.702 P 0.990 0.649 0.179 The difference in the mean values among the different levels of Treatment is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in REPS. There is not a statistically significant difference (P = 0.990). The difference in the mean values among the different levels of REPS is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in Treatment. There is not a statistically significant difference (P = 0.649). The effect of different levels of Treatment does not depend on what level of REPS is present. There is not a statistically significant interaction between Treatment and REPS. (P = 0.179) Power of performed test with alpha = 0.0500: for Treatment: 0.0500 Power of performed test with alpha = 0.0500: for REPS : 0.0500 Power of performed test with alpha = 0.0500: for Treatment x REPS : 0.194__________ 151 Table 102. Two way analysis of variance of percent AM colonization levels in Hordeum __________vulgare, 2001 continued._____________________________ S tatistical A nalysis R esults continued Least square means for Treatment Group Mean Coversoil 0.343 Control 0.343 Cvr/AM inoc. 0.348 Std Err of LS Mean ==0.0294 Least square means for REPS Group Mean 1.000 0.333 0.334 2.000 0.368 3.000 Std Err of LS Mean ==0.0294 Least square means for Treatment x REPS Group Mean Coversoil x 1.000 0.353 Coversoil x 2.000 0.375 Coversoil x 3.000 0.302 Control x 1.000 0.333 Control x 2.000 0.350 Control x 3.000 0.348 Cvr/AM inoc. x 1.000 0.315 Cvr/AM inoc. x 2.000 0.278 Cvr/AM inoc. x 3.000 0.453 Std Err of LS Mean = 0.0509 152 Table 103. Two way analysis of variance of percent AM colonization levels in _________ A gropyron trachycaulum , 2001.____________________________ S tatistical A n alysis R esults____________________________ Two Way Analysis of Variance Data source: %AM colonization levels in slender wheatgrass Balanced Design Dependent Variable: % AM colonization Normality Test: Passed (P > 0.200) Equal Variance Test: Passed (P = 0.240) Source of Variation Treatment REPS Treatment x REPS Residual Total DF 2 2 4 27 35 SS 0.0551 0.0102 0.0137 0.135 0.214 MS 0.0276 0.00512 0.00342 0.00500 0.00612 F 5.505 1.023 0.684 P 0.010 0.373 0.609 The difference in the mean values among the different levels of Treatment is greater than would be expected by chance after allowing for effects of differences in REPS. There is a statistically significant difference (P = 0.010). To isolate which group(s) differ from the others use a multiple comparison procedure. The difference in the mean values among the different levels of REPS is not great enough to exclude the possibility that the difference is just due to random sampling variability after allowing for the effects of differences in Treatment. There is not a statistically significant difference (P = 0.373). The effect of different levels of Treatment does not depend on what level of REPS is present. There is not a statistically significant interaction between Treatment and REPS. (P - 0.609) Power of performed test with alpha = 0.0500: for Treatment: 0.724 Power of performed test with alpha = 0.0500: for REPS : 0.0520 Power of performed test with alpha = 0.0500: for Treatment x REPS : 0.0500 Least square means for Treatment: Group Mean Coversoil 0.457 Control 0.443 Cvr/AM inoc. 0.532 Std Err of ES Mean = 0.0204 153 Table 103. Two way analysis of variance of percent AM colonization levels in _________ A gropyron trachycaulum , 2001 continued.___________________ S tatistical A n alysis R esults continued______________ Least square means for REPS : Group Mean 1.000 0.486 2.000 0.453 3.000 0.492 Std Err of ES Mean = 0.0204 Least square means for Treatment x REPS : Group Mean Coversoil x 1.000 0.480 Coversoil x 2.000 0.405 Coversoil x 3.000 0.485 Control x 1.000 0.440 Control x 2.000 0.455 Control x 3.000 0.433 Cvr/AM inoc. x 1.000 0.538 Cvr/AM inoc. x 2.000 0.500 Cvr/AM inoc. x 3.000 0.558 Std Err of LS Mean = 0.0354 All Pairwise Multiple Comparison Procedures (Student-Newman-Keuls Method): Comparisons for factor: Treatment Comparison Diff of Means P P0.050 P q Cvr/AM inoc. vs. Control 0.0892 3 4.366 0.013 Yes Cvr/AM inoc. vs. Coversoil 0.0750 2 3.673 0.015 Yes Cvr/AM inoc. vs. Control 0.0142 2 0.694 0.628 No Comparisons for factor: REPS Comparison Diff of Means p P P 0.050 q 3.000 vs. 2.000 0.0383 3 1.877 0.393 No 3.000 vs. 1.000 0.00583 2 0.286 0.842 Do Not Test 1.000 vs. 2.000 0.0325 2 1.591 0.270 Do Not Test A result of "Do Not Test" occurs for a comparison when no significant difference is found between two means that enclose that comparison. For example, if you had four means sorted in order, and found no difference between means 4 vs. 2, then you would not test 4 vs. 3 and 3 vs. 2, but still test 4 vs. I and 3 vs. I (4 vs. 3 and 3 vs. 2 are enclosed by 4 vs. 2: 4 3 2 I). Note that not testing the enclosed means is a procedural rule, and a result of Do Not Test should be treated as if there is no significant difference between the means, even though one may appear to exist. MONTANA state