- PROCEEDINGS -
UNIVERSIDADE FEDERAL DO PARANÁ
SETOR DE CIÊNCIAS AGRÁRIAS
DEPARTAMENTO DE SOLOS E ENG. AGRÍCOLA
NÚCLEO DE ATIVIDADES EM ENG. DE BIOSSISTEMAS
ISBN
ORGANIZING COMMITTEE
Chairman
Robson André Armindo – DSEA/UFPR
Members
Quirijn de Jong van Lier – CENA/USP
Marta Vasconcelos Ottoni – CPRM-RJ
Paulo Ivonir Gubiani – DS/UFSM
Masato Kobiyama – IPH/UFRGS
Karina Maria Vieira Cavalieri – DSEA/UFPR
Secretary
Denise de Conti – UFPR
SUPPORT COMMITTEE
Alessandra Calegari da Silva
Aline Mari Huf dos Reis
Briane Kreitlov e Silva
Carlos Maduro
Clayton Cerasomma Figueiredo
DanielaBaumann
Eduardo Teixeira da Silva
Gabriel Caus
Karllas Stival Freitas
Hemile Natani Silva Lima
Liana do Rocio Bastos de Moraes
Letícia Gonçalves Maduro
Luiza Louback Botelho
Marcieli Machado Manfio
Maria Eliza Turek
Matheus Fonseca Durães
Priscila Mayumi Gomes Ninuma
Rodrigo Yuiti Izumi
SUMÁRIO
A STRUCTURAL CLASSIFICATION SYSTEM OF THE SOIL PORE SPACE .......................................................................................... 4
Theophilo B. Ottoni Filho1, Marta V. Ottoni2,4, Henry Lin3, Otto Corrêa Rotunno Filho4 .........................................................................4
AGGREGATION OF NEOSOIL LITOLIC EUTROFIC WITH RICE HUSK ASH ......................................................................................... 5
Maria de Fátima Marchezan Menezes da Silva1, Luis Carlos Timm2, Ledemar Carlos Vahl2, Roberlaine Ribeiro Jorge3, Silvio Arthur
Neumann4 ...........................................................................................................................................................................................5
AIR-FILLED POROSITY AND PRODUCTIVITY OF IRRIGATED COFFEE IN AN OXISOL IN THE SOUTH OF MINAS GERAIS, BRAZIL6
Gabriel Democh Goularte3, Jorge Luiz Moretti de Souza1, Adão Wagner Pêgo Evangelista2, Sísara Rocha Oliveira3 ..........................6
ARE PEDOTRANSFER FUNCTIONS FOR BULK DENSITY ACCURATE IN A DIFFERENT ENVIRONMENT FROM THOSE USED TO
DEVELOP THEM? ................................................................................................................................................................................... 7
Raquel Stucchi Boschi1*, Felipe Bocca2, Maria Leonor R.C. Lopes-Assad3, Eduardo Delgado Assad1.................................................7
ASSESSMENT OF HYDRAULIC CONDUTIVITY ON CONSTRUCTED SOIL OF COAL RECLAIMED AREAS WITH THREE
DIFFERENT METHODS .......................................................................................................................................................................... 8
Souza, Fernando b.1, Back, Marcos; Souza, Émilin J.C. ......................................................................................................................8
CALIBRATION OF A CAPACITANCE WATER CONTENT PROBE IN AN AQUERTIC HAPLUDALF SOIL ............................................. 9
Alex Becker Monteiro1, Luciano Recart Romano2, Carlos Reisser Junior3, Viviane Santos Silva Terra4, Luís Carlos Timm5 ................9
CALIBRATION OF HYDRUS 2D APPLIED TO DRIP IRRIGATION OF OLIVES IN A SALINE SOIL IN THE ATACAMA DESERT ........ 10
Faúndez, C1*, C. Kremer1, O. Seguel1, J. Honorio de Miranda2 .......................................................................................................... 10
CHANGES IN SOIL WATER AND AIR AVAILABILITY AS AFFECTED BY COFFEE SLUDGE APPLICATION ..................................... 11
Freitas, K. S.1, Armindo, R. A.2, Lima, H. N. S.3 ................................................................................................................................. 11
CHANGES ON PHYSICAL ATTRIBUTES OF A CAMBISOL BY Pinus taeda PLANTATIONS ............................................................... 12
Mariana Alves Ibarr1, Bruna Ramalho1, Josiléia Acordi Zanatta2, Marcos Rachawal2, Rosana Higa2, Jeferson Dieckow1................... 12
COMPUTERIZED TOMOGRAPHY TO ANALYZE POROSITY DISTRIBUTION REPRESENTATIVE ELEMENTARY AREA IN SOILS
FROM THE SOUTHEAST OF BRAZIL ................................................................................................................................................... 13
Talita R. Ferreira1, Luiz F. Pires ......................................................................................................................................................... 13
DEVELOPMENT OF AN EQUIPMENT AND A DATA ACQUISITION SYSTEM FOR THE DETERMINATION OF THE SOIL
PERMEABILITY TO AIR ........................................................................................................................................................................ 14
Figueiredo, C. C1., Armindo, R. A2., Silva, E. T2. ................................................................................................................................ 14
DIGITAL IMAGE PROCESSING APPLIED TO X-RAY MICROTOMOGRAPHY TO INVESTIGATE POROUS SPACE AND WATER
WITHIN SOIL SAMPLES ........................................................................................................................................................................ 15
Tseng Chien Ling1, Rodrigo Henrique Gounella2, Marlene Cristina Alves3, Carlos Manoel Pedro Vaz4, Silvio Crestana4.................... 15
EFFECT OF BIOCHAR ON THE WATER HOLDING CAPACITY OF THE BRAZILIAN SOILS EXEMPLIFIED BY SANDY NORTHEAST
SOIL....................................................................................................................................................................................................... 16
Estela M. C. Cardoso1*, Marta E. Doumer1, Juliana Shultz1, Antonio S. Mangrich1,2, Luciane P. C. Romão2 e Etelvino H. Novotny3 .. 16
EFFECTS OF SOIL COMPACTION IN DEVELOPMENT CORN ROOT ................................................................................................. 17
Maria de Fátima Marchezan Menezes da Silva1, Jéssica Pedroso Rosado1, Wildon Panziera1, Ledemar Carlos Vahl2, Cláudia Liane
Rodrigues de Lima2 ........................................................................................................................................................................... 17
EFFECTS OF SURFACE APPLICATION OF GYPSUM IN THE SOIL PHYSICAL PROPERTIES AND YIELD OF CORN
INTERCROPPED WITH JACK BEAN (Canavalia eusiformis)................................................................................................................. 18
SEIDEL, E. P1; REIS, W. dos2; MOTTIN, M.C3. ................................................................................................................................. 18
EMPIRIC MODEL FOR THE PREDICTION OF CAPILLARY RISE OF WATER, GASOLINE AND DIESEL OIL IN SOIL ....................... 19
Robson André Armindo1, Clayton Cerasomma Figueiredo2, Letícia Gonçalves2 ................................................................................ 19
ESTIMATING BULK DENSITY FOR CALCULATING CARBON STOCK IN DIFFERENT BRAZILIAN AGROECOSYSTEMS ................ 20
Raquel Stucchi Boschi1, Maria Leonor Lopes-Assad2, Gabriela P. S. Souza2, Ana C. M. Cidin2, Eduardo Delgado Assad1 ............... 20
ESTIMATING LEACHATE GENERATION BY A LANDFILL USING THE HYDRUS CODES .................................................................. 21
Kymie Saito1, Martinus Th. van Genuchten1,2, Otto C. Rotunno Filho1, and Webe J. Mansur1 ............................................................ 21
EVALUATION OF DIFFERENT PARAMETERIZATIONS FOR THE VAN GENUCHTEN SOIL WATER RETENTION FUNCTION ........ 22
Marta V. Ottoni1,4, Theophilo B. Ottoni Filho2, Martinus Th. van Genuchten3 and Otto C. Rotunno Filho4 ........................................... 22
EVALUATION OF TWO DIFFERENT CONSTANT-HEAD CONTROLLER UNITS OF AUTOMATIC PERMEAMETER (PA-LHG) FOR IN
SITU MEASUREMENT OF FIELD-SATURATED HYDRAULIC CONDUCTIVITY ................................................................................... 23
Lange, D. R.1, Santos, I.2; .................................................................................................................................................................. 23
FORECASTING CROP EVAPOTRANSPIRATION FROM ENSEMBLE-BASED NUMERICAL WEATHER FORECASTS AND HIGH
RESOLUTION SATELLITE IMAGES ...................................................................................................................................................... 24
Hanoi Medina González 1, Anna Pelosi2, Paolo Villani2, Guido D’Urso3, Salvatore Falanga Bolognesi4, Giovanni Battista Chirico5 .... 24
GRANULOMETRIC ANALYSES OF SOME SANDY SOILS FORM NORTHERN MINAS GERAIS ........................................................ 25
João Herbert Moreira Viana1, Guilheme Kangussu Donagemma2...................................................................................................... 25
INFLUENCE OF WINTER COVER CROPS ON PHYSICAL PROPERTIES OF THE SOIL .................................................................... 26
Mottin, M.C.1, Seidel, E.P.2, Fey, E. 2; Richart, A. 3, Vanelli, J. 1; Alves, A.L. 1, Schneider, A.P.H. 4, Sustakowski, M. 4 ......................... 26
MODELLING THE WATER FLUX IN A RHODIC EUTRUDOX UNDER TILLAGE SYSTEMS................................................................. 27
Moacir Tuzzin de Moraes1, Henrique Debiasi2, Michael Mazurana3, Julio Cezar Franchini2, José Antônio Louzada4, Renato Levien . 27
MODELS OF WATER MANAGEMENT UNITS FROM THE SPATIAL VARIABILITY OF PHYSICAL AND HYDRAULIC SOIL
PROPERTIES ........................................................................................................................................................................................ 28
Silva, B. K1., Armindo, R. A.2, Sobenko, L. R.3, Ceresoli, L. L.4 .......................................................................................................... 28
PERFORMANCE OF SPLINTEX PROGRAM ON SOIL WATER RETENTION CURVE PREDICTION CONSIDERING THE ABSENT OF
WATER CONTENT MEASUREMENTS ................................................................................................................................................. 29
Reis, A.M.H1, Armindo, R.A2, Durães, M.F. 2 ...................................................................................................................................... 29
PERFORMANCE OF PEDOTRANSFER FUNCTIONS TO SIMULATION OF SPATIAL VARIABILITY OF THE SOIL HYDRAULIC
FUNCTIONS .......................................................................................................................................................................................... 30
Silva, A.C.1, Armindo, R.A.2, Brito, A.S.3, Silva, E.T.2 ......................................................................................................................... 30
PHYSICAL ATTRIBUTES OF AN OXISOL WITH SOYBEAN CROP UNDER DIFFERENT AGES IN PIAUIENSE CERRADO .............. 31
Leovanio Rodrigues Barbosa1, Francisco Rafael Da Silva 2, Rolff Vladimir Mitton 3, Luís Alfredo Pinheiro Leal Nunes 4 .................... 31
PHYSICO-HYDRICAL ATTRIBUTES OF AN ALBAQUALF CULTIVATED UNDER CONVENTIONAL TILLAGE AND NO-TILLAGE
SYSTEMS .............................................................................................................................................................................................. 32
Bruno César Gurski1, Jorge Luiz Moretti de Souza1, Daniela Jerszurki1 ............................................................................................. 32
PRESERVING HETEROGENEITY AND CONSISTENCY IN HYDROLOGICAL MODEL INVERSIONS BY ADJUSTING
PEDOTRANSFER FUNCTIONS. ........................................................................................................................................................... 33
Marcel G. Schaap1, Yonggen Zhang1,2, Chi Xu2,3 ............................................................................................................................... 33
RELATIONSHIP OF SOIL PHYSICAL PARAMETERS WITH SORPTIVITY AND HYDRAULIC CONDUCTIVITY .................................. 34
Adalberto Alves Pereira¹, Edivaldo Lopes Thomaz² ........................................................................................................................... 34
RESILIENCE OF SOILS WITH DIFFERENT ORGANIC MATTER, TEXTURE AND MINERALOGY IN LONG-TERM NO-TILLAGE
SYSTEMS .............................................................................................................................................................................................. 35
J. A. Bonetti 1, 2, I. Anghinoni 1, M. T. Moraes 1 and J. R. Fink 1 ........................................................................................................... 35
ROOT VOLUME OF PERENNIAL GRASSES AND THEIR RELATION TO THE AGGREGATION OF A CONSTRUCTED SOIL AFTER
COAL MINING ....................................................................................................................................................................................... 36
Luiz Fernando Spinelli Pinto1,2, Lizete Stumpf2, Eloy Antonio Pauletto2, Fabrício da Silva Barboza2, Leonir Aldrighi Dutra Junior2,
Luciano Oliveira Geissler2, David de Lima de Souza2, Renata Pinto Albert2....................................................................................... 36
SAND SETTLING TIME FOR DETERMINATION OF TEXTURE CLASS OF AN INCEPTISOL .............................................................. 37
Bruno Vizioli1, Mariana Alves Ibarr1, Sísara Rocha Oliveira1 .............................................................................................................. 37
SHEAR STRENGTH PARAMETERS OF MATERIALS FROM A LANDSLIDE SCAR............................................................................. 38
Graziela Maziero Pinheiro Bini1, Jéssica Gerente2, Edna Lindaura Luiz3............................................................................................ 38
SIMULATION OF SOIL HYDRAULIC FUNCTIONS BY PEDOTRANSFER FUNCTIONS - SPLINTEX AND ROSETTA ......................... 39
Silva, A.C.1, Armindo, R.A.2, Brito, A.S.3, Silva, E.T.2 ......................................................................................................................... 39
SOIL ATTRIBUTES OF AMAZON UNDER DIFFERENT USES: AN APPROACH BASED ON DECISION TREE ................................... 40
*
Raquel Stucchi Boschi1 , Laura Fernanda Simões da Silva2, Maria Leonor Lopes-Assad3, Luiz Henrique Antunes Rodrigues4, Miguel
Cooper2 ............................................................................................................................................................................................. 40
SOIL BULK DENSITY AND SHAPE OF SWEET POTATO ROOT UNDER DIFFERENT SOIL MANAGEMENTS .................................. 41
Amarílis Beraldo Rós ......................................................................................................................................................................... 41
SOIL COMPACTION ASSESSMENT FOR DIFFERENT AMOUNTS OF SURFACE STRAW UNDER NO BURN SUGARCANE
CULTIVATION IN A CLAYEY SOIL ........................................................................................................................................................ 42
Henrique Pose Guerra1,2, Izaias Pinheiro Lisboa1,3, Caio Fernandes Zani1,4, Carlos Clemente Cerri1,5 ............................................... 42
SOIL EROSION RELATED PROCESSES IN A SMALL SUGARCANE WATERSHED OF SOUTHEAST BRAZIL ................................. 43
Taciana Figueiredo Gomes; Robson Willians da Costa Silva, Jorge Marcos de Moraes, Edmar Mazzi; Luiz Antonio Martinelli ......... 43
SOIL HYDRAULIC PROPERTIES AND ITS IMPLICATIONS FOR OVERLAND FLOW GENERATION IN SUGARCANE PLANTATION
AND RIPARIAN FOREST....................................................................................................................................................................... 44
Robson Willians da Costa Silva, Luiz Felippe Salemi, Rafel Pires Fernandes, Taciana Figueiredo Gomes, Jorge Marcos de Moraes,
Luiz Antonio Martinelli........................................................................................................................................................................ 44
SOIL MANAGEMENT SYSTEM EFFECTS ON SOIL WATER MOVEMENT UNDER NON-SATURATED CONDITIONS ...................... 45
Rafael Villarreal1*, Luis A. Lozano1, C. Germán Soracco1, Guillermo O. Sarli1.................................................................................... 45
SOIL PERMEABILITY COEFFICIENT TO VINASSE APPLICATION...................................................................................................... 46
Morais, L.R.B.1, Armindo, R.A.2 ......................................................................................................................................................... 46
SOIL PHYSICAL ATTRIBUTES: SUSTAINABILITY ASSESSMENT IN CROP-LIVESTOCK-FOREST SYSTEMS ................................. 47
Alcione Herminia da Silva1, Verediana Fernanda Cherobim 1, Daniela Jerszurki1, Nerilde Favaretto2, Karina Maria Vieira Cavalieri2,
Jeferson Dieckow2, Lucilia Maria Parron3........................................................................................................................................... 47
Coblinski, J.A.1, Goularte, G.D.1, Favaretto, N.2, Dieckow, J.2, Moraes, A.3 ........................................................................................ 48
SOIL SURFACE TEMPERATURE UNDER OAT RESIDUE ESTIMATED FROM METEOROLOGICAL DATA ....................................... 49
Anderson Luiz Zwirtes¹*, Dalvan José Reinert¹, Paulo Ivonir Gubiani¹ Eduardo Augusto Müller¹ ........................................................ 49
SPATIAL VARIABILITY OF LATOSOLS (OXISOLS) STRUCTURE SUBJECTED TO THE COFFEE CULTIVATION OF DIFFERENT
AGES ..................................................................................................................................................................................................... 50
Carducci, C.E.1, Oliveira, G.C.2, Rossoni, D.F.3 ................................................................................................................................. 50
SPATIAL VARIABILITY OF PHYSICAL ATTRIBUTES AND OF THE SOIL PERMEABILITY TO WATER AND FUELS ......................... 51
Gonçalves, L.1, Armindo, R. A.2, Turek, M. E.3; Botelho, L.L. 4, Souza, J. L. M.5 ................................................................................. 51
SPATIAL VARIABILITY OF PHYSICAL ATTRIBUTES IN AN ULTISOL IN LAND USE OF SUGARCANE, PASTURE AND NATIVE
FOREST ................................................................................................................................................................................................ 52
Teresa Cristina T. Pissarra1, Fabiana C. Reis2, Sergio Campos3 ....................................................................................................... 52
SPIA: A SOFTWARE FOR MICROMORPHOMETRIC CHARACTERIZATION OF PORES FROM 2D IMAGE ANALYSIS .................... 53
Miguel Cooper1*, Raquel Stucchi Boschi2, Vitor Boschi da Silva3, Laura Fernanda Simões da Silva4................................................. 53
SURFACE AND INCORPORATED LIME EFFECTS ON SOME PHYSICAL ATTRIBUTES OF A DYSTRUDEPT .................................. 54
André Carlos Auler1*, Luiz Fernando Pires2, Neyde Fabíola Balarezo Giarola2, Eduardo Fávero Caires2, José Alfredo Baptista dos
Santos3.............................................................................................................................................................................................. 54
TENSILE STRENGTH OF AN ALFISOL UNDER DIFFERENT DOSES OF RICE HUSK ASH ............................................................... 55
Ivana Kruger Tuchtenhagen1, Cláudia Liane Rodrigues de Lima2, Eloy Antonio Pauletto2, Ledemar Carlos Vahl2, Lizete Stumpf2,
Rodrigo Brum de Paiva2 .................................................................................................................................................................... 55
VARIABILITY AND SPATIAL DEPENDENCE OF PHYSICAL ATTRIBUTES OF AN OXISOL UNDER DIFFERENT ROW SPACING
CONFIGURATIONS OF SUGARCANE .................................................................................................................................................. 56
Wildon Panziera¹, Cláudia Liane Rodrigues de Lima, Sergio Delmar dos Anjos e Silva, Eloy Antonio Pauletto, João Roberto
Pimentel, Leonir Aldrigi Dutra Junior .................................................................................................................................................. 56
VARIABILITY OF SOIL HYDRAULIC PARAMETERS AND ITS IMPACT ON AGRO- HYDROLOGICAL MODEL PREDICTIONS ......... 57
Thalita Campos Oliveira1, Quirijn de Jong van Lier2 ........................................................................................................................... 57
4
A STRUCTURAL CLASSIFICATION SYSTEM OF THE SOIL PORE SPACE
Theophilo B. Ottoni Filho1, Marta V. Ottoni2,4, Henry Lin3, Otto Corrêa Rotunno Filho4
1
Department of Water Resources and Environment, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil. 2Department of
Hydrology, Geological Survey of Brazil (CPRM), Rio de Janeiro, RJ, Brazil. corresponding author: marta.ottoni@cprm.gov.br.
3
Department of Ecosystem Science and Management, The Pennsylvania State University,University Park, Pennsylvania, PA, USA.
4
Civil Engineering Program/COPPE, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
The concept of soil structure does not yet have a consolidated means of quantification, but
it plays an important role because of its significance in the understanding and
representation of flow and transfer phenomena in soils. An useful way of quantifying soil
structure is to consider pore-size distribution (PSD) equal to effective air saturation
calculated as an increasing function of soil water suction. Based on similarities between
the particle-size distribution and the PSD curves, a structural classification system of soil
pore space is developed, which is comparable to the textural classification. Three poresize fractions are arbitrarily defined in the effective porous space, as: effective
macroporous space (0-60cm suction); effective mesoporous space (60-15,000cm suction);
and effective microporous space (suctions larger than 15,000cm). For the sake of
classification, the effective porous space is subdivided into three fractions: 0-1/3, 1/3-2/3,
and 2/3-1. The three pore-size fractions sum up to 1, allowing a soil sample to be
represented in an equilateral triangle, we called soil structural triangle. The resulting nine
subareas in the triangle (three pore-size fractions x three porous space fractions)
represent the nine orders (from A to I) of the classification system, namely: A - highly
macroporous; C - highly mesoporous; I - highly microporous; D - macroporous; E mesoporous; H - microporous; B - macro-mesoporous; G - meso-microporous; and F macro-microporous. This system aims to group soils with similar air availability (AA) curves
(air content vs. suction). So, the van-Genuchten model for water retention is assumed and
effective porosity is determined in a standardized manner. Four suborders (from 1 to 4) are
then further used to represent effective porosity ranges, respectively: 0-0.20; 0.20-0.40;
0.40-0.60; and >0.60cm3.cm-3. The resulting 36 soil classes assemble samples with similar
AA curves. They are called soil structural families. A large international database with
more than 3000 soil samples from Europe and Brazil was used to evaluate the proposed
system. It is confirmed that the families grouped soils with similar AA curves and only three
structural families were not represented in the database. The results also show that soils
with different textures and pedogenesis can behave similarly in terms of pore-size
distribution: a typical case was clayed tropical soils joining the sandy European soils in the
macroporous orders A and D. More frequently, sandy soils were in the macroporous
orders, silty soils in the mesoporous, and clayey soils in the microporous orders. The
proposed system can contribute to the enhanced understanding and modeling of soil
structural behavior, including a better formulation of pedotransfer functions.
Keywords: Pore-size distribution; soil structure; soil classification.
5
AGGREGATION OF NEOSOIL LITOLIC EUTROFIC WITH RICE HUSK ASH
Maria de Fátima Marchezan Menezes da Silva1, Luis Carlos Timm2, Ledemar Carlos
Vahl2, Roberlaine Ribeiro Jorge3, Silvio Arthur Neumann4
1
Doctoral Student, Graduate Program in Management and Conservation of Soil and Water, UFPel, mfmarchezan@gmail.com;
Teacher, UFPel; 3Teacher, UNIPAMPA; 4Agronomist, Cooperativa Agroindustrial Alegrete Ltda.
2
The rice husks have been used by grain processing agribusinesses as biomass to
generate energy and drying of grains, which annually generate thousands of tons of a
byproduct called rice husk ash (RHA), whose fate is the disposal in environment and
deposition in pastures or crops without any assessment of their impact on the
environment. However, there is the possibility that this residue can be used as a corrective
and a soil conditioner, requiring ways to secure their use. The work was to evaluate the
physical condition of the Neosoil Eutrophic with irrigated rice BR-IRGA 409, eight months
after the incorporation of RHA, for two consecutive years, using indicators of the physical
attributes as Diameter Weighted Average (DWA) stable aggregates in water and the
proportion of macro (Ma) and micro aggregates (Mi) for each treatment in two layers of the
soil (0.0 - 0.10 and 0.10 - 0.20 m). The experimental design was a randomized block
consisting of six treatments with four replications: fallow area (Tp), 0 (T0), 4 (T1), 8 (T2),
16 (T3) and 32 t (T4) CCA ha-1 per year. Data were subjected to analysis of variance
(ANOVA) and the means compared using the Tukey test at 5% significance when there
were differences between treatments. In the first year of evaluation the no were statistical
differences between the values of DWA, Ma and Mi, evaluated in both layers and between
treatments were not observed. In the second year with other incorporating, were statistical
differences in percentages of DWA and micro-aggregates between the fallow and the
treatments T0, T1, T2, T3 only in the layer 0.10 to 0.20 m. However, there was no
statistical difference between the fallow (Tp) and the treatment with 64 t ha -1 RHA in the
same layer.
Keywords: Soil physical attributes; rice, soil conditioner; correction of soil.
6
AIR-FILLED POROSITY AND PRODUCTIVITY OF IRRIGATED COFFEE IN AN OXISOL
IN THE SOUTH OF MINAS GERAIS, BRAZIL
Gabriel Democh Goularte3, Jorge Luiz Moretti de Souza1, Adão Wagner Pêgo
Evangelista2, Sísara Rocha Oliveira3
1
Federal University of Paraná, Soil Science and Agricultural Engineering Department, Rua dos Funcionários, 1540, CEP 80035-050,
Curitiba, PR, Brazil. E-mail: jmoretti@ufpr.br. 2 Federal University of Goiás; 3 Graduate in Soil Science.
Air-filled porosity () is important for crops, being directly related to the development of
roots and plant. The temporal evaluation of  in the soil, as well as determining the optimal
range of its values, helps to improve the planning and management of irrigation systems,
environmental conservation, maintaining the physical quality of the soil and yields,
consequently. The objective of this study was to evaluate the temporal variation of air-filled
porosity in an Oxisol and determine the optimal range to obtain the best yield of irrigated
coffee in Lavras-MG, Brazil. The experiment was conducted between the years 20072008, with coffee cultivar Rubi MG-1192, planted in March 1999, with spacing of 3.5 m
between rows and 0.8 m between plants. The experimental design was a randomized
block design with six treatments and three replications. The treatments consisted of
applying percentages of necessary irrigation depth (Li) and 0 (non-irrigated) and 60, 80,
100, 120 and 140% of Li. Irrigation was done in two-three days irrigation frequency
(Mondays, Wednesdays and Fridays). The matric potential of soil water ( m) in each
treatment was measured by the watermark type sensors installed at three depths (0.25,
0.50 and 0.75 m). The sensors were connected to dataloggers with hourly readings. The
volumetric moisture to calculate the hourly air-filled porosity in the treatments was
determined using the soil water retention curves. The results were submitted to a
descriptive and exploratory analysis of average, coefficient of variation and frequency. The
Tukey Test was used to compare average values (p<0.05). There were no significant
differences in the productivity between T0 treatments (non-irrigated, 3516 kg ha−1), T60
(4740 kg ha−1) and T80 (6132 kg ha−1). However, increasing water depth increased yields
until treatment T100 (8980 kg ha−1). The T120 treatments (7656 kg ha−1) and T140 (7278
kg ha−1), although statistically equal to T100, provided decreasing yields. Increasing
irrigation regimes provided linear reduction of average  for the 13,199 temporal data
analyzed (R2 = 0.9976). The highest amplitudes of  occurred in treatments with higher
applied water depths. The irrigation management in treatment T100 provided better soil
aeration and good conditions for the development of the crop, allowing higher yields. Soil
air-filled porosity () between 0.152 to 0.163 m3 m3 was ideal to root system of coffee-tree
cultivated in this Oxisol, and can be recommended to establish the limits of soil moisture
for irrigation management.
Keywords: Irrigated agriculture; air-filled porosity; yield, coffee.
7
ARE PEDOTRANSFER FUNCTIONS FOR BULK DENSITY ACCURATE IN A
DIFFERENT ENVIRONMENT FROM THOSE USED TO DEVELOP THEM?
Raquel Stucchi Boschi1*, Felipe Bocca2, Maria Leonor R.C. Lopes-Assad3, Eduardo
Delgado Assad1
1
Embrapa Agriculture Informatics, 2School of Agricultural Engineering, Univ. of Campinas, 3Center of Agricultural Sciences, Federal
Univ. of São Carlos. *Corresponding author (raboschi@gmail.com).
Bulk density (ρb) is an important soil physical property known to affect a diversity of soil
properties, e.g. porosity, root density, soil water movements. This property has received
particular attention due to its importance to weight-to-volume conversion used to assess
soil carbon (SOC) stocks. Despite its importance, ρb lacks databases once its direct
measurement is labor intensive, time-consuming, and expensive. Furthermore, ρb is highly
variable in space and time. Pedotransfer functions (PTFs) have been widely used to
estimate ρb through soil properties that are easier to measure and available in most
databases. The objective of this study was to evaluate the performance of PTFs available
in the literature to estimate ρb in soils of different Brazilian regions. We present the
Regression Error Characteristic (REC) curve as a model assessment methodology, along
with the metrics traditionally used. The REC curve is a promising alternative for the
evaluation of this type of model. This curve allows us to compare the performance of
different models simultaneously and by visual assessment, which facilitates the
interpretation by the user. The REC curve displays the error along the X axis and the
percentage of points within each error value in the Y axis. With this construction, we can
evaluate levels of accuracy as the number of points for different margins of error. We
selected for testing 25 available PTFs. The data set used to evaluate the PTFs was
composed by 884 samples of Brazilian soils. The predict quality of the PTFs was
determined based on the REC curve and the following indices: mean absolute error
(MAE), mean error (ME), root mean squared error (RMSE) and coefficient of determination
(R2). The ρb values were underestimated by 23 of the 25 PTFs. The MAE ranges from
0.17 g cm-3 to 0.50 g cm-3 whereas the RMSE range from 0.19 g cm -3 to 0.45 g cm-3 and
the R2 from 0.05 to 0.41. The 25 PTFs showed a performance close to the null model
when estimating ρb for soils from different regions of Brazil. We concluded that the
performance of the models compared to the null model indicates no effective gain in its
use. The application of the REC curve as a form of analysis allowed a simple and visual
evaluation of the performance of the models.
Keywords: REC curve; tropical soil; model validation; pedotransfer functions.
8
ASSESSMENT OF HYDRAULIC CONDUTIVITY ON CONSTRUCTED SOIL OF COAL
RECLAIMED AREAS WITH THREE DIFFERENT METHODS
Souza, Fernando b.1, Back, Marcos; Souza, Émilin J.C.
1
fbs@unesc.net, Universidade do Extremo Sul Catarinense
Hydraulic conductivity is an inherent property of a porous media which represents the
liquid's easiness to pass through this porous media. In the ecological restoration of coal
mining sites, hydraulic conductivity has been used to assess constructed soils' structure
development. Then, three methods were used to assess and compare hydraulic
conductivity measurement on constructed soils of two reclaimed sites aging 5 years
(RS01) and 7 years (RS02), located in Treviso and Siderópolis, respectively (both in Santa
Catarina State - Brazil). The evaluated methods were: Control (laboratory constant head
with undisturbed sample); Permeameter A (constant head in shallow borehole) and
Permeameter B (falling head in shallow cased borehole). Three tests were done on each
reclaimed site and for each method. The hydraulic conductivity was calculated by
Embrapa, Glover and ASTM equations for Control, Permeameter A and Permeater B,
respectively. The mean and standard deviation observed on RS01 was 2,5 x 10-5 ± 3,93 x
10-5 cm.s-1 for control; 1,9 x 10-4 ± 1,6 x 10-4 cm.s-1 for permeameter A and 8,5 x 10-5 ± 1,3
x 10-4 cm.s-1 for permeameter B. While measurements on RS02 were 2,2 x 10-5 ± 3,3 x 105 cm.s-1 for control; 2,5 x 10-4 ± 1,8 x 10-4 cm.s-1 for permeameter A and 2,2 x 10 -5 ± 3,0 x
10-5 cm.s-1 for permeameter B. Besides the expressive variation derived from a
heterogeneous soil, these low values are related to the predominantly pelitic material used
as new soil for vegetation growth and land reclamation. Furthermore, specific
characteristics (open and cased borehole) of each permeameter and the different
calculations processes must be considered for these variations. Statistically analyzing the
values (ANOVA), there is no significant difference (p < 0,05) between the permeameters
and the control in both sites. The p-values found (comparing with the control method) with
the permeameter A was pRS01 = 0,40 and pRS02 = 0,08, while for the permeameter B was
pRS01 = 0,99 and pRS02 = 1,00. Hydraulic conductivity on constructed soils has shown highly
spatial variation, even if using different methods of assessment or if the soil has two years
of difference between their reclamation. Therefore, new studies need to be done to
evaluate these constructed soils.
Keyword: Hydraulic conductivity; land reclamation constructed soil.
9
CALIBRATION OF A CAPACITANCE WATER CONTENT PROBE IN AN
AQUERTIC HAPLUDALF SOIL
Alex Becker Monteiro1, Luciano Recart Romano2, Carlos Reisser Junior3, Viviane Santos
Silva Terra4, Luís Carlos Timm5
1
Master student at PPG-Management and Conservation of Soil and Water (PPG-MACSA), Faculdade de Agronomia Eliseu Maciel
(FAEM)/Universidade Federal de Pelotas (UFPel), Bolsista da FAPERGS (alexbeckermonteiro@gmail.com); 2PhD student at PPGMACSA/FAEM/UFPel, Assistant Professor at IFMT-Campus Cáceres; 3Researcher at Embrapa Clima Temperado;4PPG on Water
Resources (PPG-RH)/UFPel, Bolsista PNPD-CAPES; 5Associate Professor at FAEM/UFPel.
Several methods are used to measure the soil water content (SWC) under field conditions.
Among them, we can mention the indirect method based on the frequency domain
reflectometry (FDR) which is constituted by a sensor capacitance probe capable of
continuous measurement of SWC. Measurement of the capacitance gives the dielectric
constant, hence the water content of the soil. Since the soil composition affects its
capacitance, there is a need to make a calibration of the probe under field conditions. The
objective of this work was to calibrate the capacitance probe model Diviner 2000® for two
textural classes of an Aquertic Hapludalf soil as well as to compare its performance with
three equations from the literature. The study was carried out in a peach orchard in the
municipality of Morro Redondo, Rio Grande do Sul state, Southern of Brazil. The soil in the
experimental area was classified as an Aquertic Hapludalf. By using the capacitance
probe, measurements of soil water content were performed at soil depths of 0.10, 0.20 and
0.30 m during a period of 30 days. At the same depths, no-preserved soil samples were
collected at a distance of 0.10 m of the probe access tube aiming to determine the SWC
as gravimetric basis which was multiplied by the soil density to obtain the SWC as
volumetric basis (θ). Potential and linear models were adjusted to estimate θ for each soil
depth and texture. The performance of both models was compared with the
manufacturer’s calibration curve as well as with three calibration curves from the literature.
Results show that the best model to estimate θ was the potential model for all three
evaluated soil depths and two textural classes. The adjusted linear model overestimated θ
values in our field conditions. The manufacturer’s calibration curve shows good estimate of
θ to soils with sandy clay loam texture and all three evaluated equations, in a general way,
also overestimated the values of θ in the experimental area.
Keywords: FDR; soil texture; soil water content; mathematical models.
10
CALIBRATION OF HYDRUS 2D APPLIED TO DRIP IRRIGATION OF OLIVES IN A
SALINE SOIL IN THE ATACAMA DESERT
Faúndez, C1*, C. Kremer1, O. Seguel1, J. Honorio de Miranda2
1
Departamento de Ingeniería y Suelos, Facultad de Cs. Agronómicas, Universidad de Chile *cfaundezu@ug.uchile.cl 2Professor
Associado 2, Departamento de Engenharia de Biossistemas, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São
Paulo.
Currently, the zone between Copiapó and Santiago of Chile is under a drought, which
generates difficulties in the fruit production. Copiapó is a city of Atacama Region, which
has a desert climate with only 22 mm of annual rainfall, the soils can be classified as
moderately saline to extremely saline, with an electrical conductivity (EC) measured in
saturation extract (ECe) from 2.5 to 19.1 dS/m. The water and salt management in olive
orchards in the Copiapó Valley is being done without the appropriate technology and
supervision, which may causes a water overestimate by the farmers, causing hypoxia, or
conversely a constant salinization of the soil profile. There are many forms to deal with this
problem, most of them is focused on the resolution of a mass and energy balance in the
continuum soil-plant-atmosphere. One of these methods is the numerical simulation with
the software HYDRUS, which solved the Richard’s equation for water flux and the
Advecto-Dispersive equation for heat and solute transport in the soil. Accordingly, it was
proposed to calibrate a water and solute balance with the HYDRUS 2D model in a saline
soil condition with olives under drip irrigation and to validate it with TDR disposed in the
plant row under the drip irrigation system. The methodology considered the installation of
five TDR sensors (model GS3, Decagon Devices, Inc. Pullman, USA) in a layered soil
(loam to silty clay loam). It was measured the volumetric water content, (WC) and the
solution electrical conductivity (ECp), comparing them with the simulated values from
HYDRUS 2D calibrated with soil water retention curve, saturated hydraulic conductivity
and inverse solutions of each layer of the soil profile. It was evaluated the relative root
mean square error (RRMSE) and Nash as reliability criteria. The obtained results shown a
RRMSE of 13.8% and 29% and a Nash of 0.64 and 0.72 for WC and CEp respectively.
This results show that HYDRUS is an alternative tool for arid zones, where it can simulate
the soil water content and pore electrical conductivity with high confiability.
Keywords: Mass balance; water flux; solute transport; solution electrical conductivity;
TDR, numerical simulation; arid zone.
11
CHANGES IN SOIL WATER AND AIR AVAILABILITY AS AFFECTED BY COFFEE
SLUDGE APPLICATION
Freitas, K. S.1, Armindo, R. A.2, Lima, H. N. S.3
Master’s Student from Soil Science Post Graduation Program - Federal University of Paraná (UFPR). karllas.stival@gmail.com.
Professor from Soils and Agricultural Engineering-UFPR. 3Agronomy Student from Federal University of Paraná.
1
2
Coffee sludge is a potential polluting residue that may cause environmental problems,
therefore its proper disposal is important. In this study, we aimed to find a sustainable
destination for coffee left-overs in the soil and evaluated their effect on soil water retention
and air content. To do so, we determined the soil water content and air-filled porosity in
containers with coffee sludge at concentrations of 0%, 5%, 10%, 15% and 20% by wet
mass. We then calculated container capacity (CC) and air-filled porosity to generate charts
to determine the soil wet mass; the masses of the containers were measured
subsequently for three days. In sequence, these containers were transferred to a
greenhouse and lettuce seedlings were transplanted to the containers. Leaf Area Index
was measured in each treatment, and the survival time of plants after cessation of
irrigation was determined. It was concluded that the treatments with 5%, 10% 15% and
20% showed container capacity values greater than the treatment without coffee sludge.
The addition of coffee sludge resulted in a smaller plant growth when compared to the
control, possibly due to lower air-filled porosity in the containers with coffee. Plants with
coffee sludge showed increased survival time when compared to the control. The
treatment without coffee sludge had the highest values of total mass and dry mass, due to
increased aeration porosity present in this treatment.
Keywords: Container capacity; soil water retention; leaf area index; coffee sludge.
12
CHANGES ON PHYSICAL ATTRIBUTES OF A CAMBISOL BY Pinus taeda
PLANTATIONS
Mariana Alves Ibarr1, Bruna Ramalho1, Josiléia Acordi Zanatta2, Marcos Rachawal2,
Rosana Higa2, Jeferson Dieckow1
1
Federal University of Paraná. E-mail: marianaibarr@gmail.com; E-mail: bruu.ramalho@hotmail.com; jefersondieckow@ufpr.br;
Embrapa Florestas. E-mail: josileia.zanatta@embrapa.br; marcos.rachwal@embrapa.br; rosana.higa@embrapa.br.
2
Conversion of natural ecosystems into planted forests may change soil physical
properties. Unlike annual crops, forest plantations can restore soil properties due to the
high contribution and cycling of tree biomass. The objective of this study was to evaluate
changes on soil physical attributes by cultivation of pine (Pinus taeda) in a clayey
Cambisol of Subtropical Brazil. In a chronosequence of mixed ombrophylous forest at mid
successional stage (MN), pasture (Pennisetum clandestinum) 20 years (P), pine plantation
with eight years in first rotation (P8), and pine plantation with three years in the second
rotation and 35 years in total (P40), undisturbed soil samples were collected in the 0-5, 510, 10-20 and 20-30 cm depth to assess soil microporosity, macroporosity and bulk
density. The conversion of MN for P did not change soil density, but decreased macro and
increased microporosity, possibly due to the effect of cattle trampling. The cultivation P8
following the pasture crop increased soil density below 10 cm, but the following cultivation
P40 reestablished the physical properties of soil subsurface by decreasing density. Soil
disturbances by planting operations in P8 may have influenced the best values of density
and porosity in the layer 0-5 cm, as in P40, the presence of heavy machinery for the
harvest of the first rotation population may have influenced the compression this layer.
Thus, the conversion of natural ecosystems into a first pine plantation negatively affected
soil physical properties, but a second pine rotation recovered those properties.
Keywords: Land use change; forestry systems; pasture.
13
COMPUTERIZED TOMOGRAPHY TO ANALYZE POROSITY DISTRIBUTION
REPRESENTATIVE ELEMENTARY AREA IN SOILS FROM THE SOUTHEAST OF
BRAZIL
Talita R. Ferreira1, Luiz F. Pires
1
State University of Ponta Grossa (UEPG)
The computed tomography (CT) represents a technique that provides images of samples,
allowing the study of different soil physical phenomena by qualitative and quantitative
analysis in 2D and 3D. In the Soil Science field any soil physical property measurement
should be representative. Total porosity ( ) is a measure of the soil porous space and its
evaluation also needs to be carried out with samples of adequate sizes. The soil
represents a heterogeneous porous medium with ϕ varying in the space, but also as a
function of the measure scale. The main objective of this study was to use the gamma ray
computerized tomography (CT) technique to define the representative elementary area
(REA) from the soil sample distribution analysis. Having this purpose in mind, three soils
with different textures were analyzed: Geric Ferralsol (GF), Rhodic Ferralsol (RF) and
Eutric Nitosol (EN). A first generation tomograph equipped with 241Am gamma-ray source
was used in the image acquisition. The selection of areas in the CT images were made
according to three different schemes: consecutive areas increasing from a first area
selected at the center of the image (scheme 1), consecutive areas increasing from a first
area selected at the inferior (scheme 2) and superior (scheme 3) borders of the sample,
with size areas ranging from 1.2 to 678.8 mm². In this study, the full width at a half
maximum (FWHM) parameter was used to describe the samples distribution in each
area. Therefore, the following criteria were adopted: 1) Relative deviation (RD) between
the FWHM value corresponding to the last area and the FWHM value obtained for each of
the selected areas in the CT image not over 10, 8, 6, 4 or 2%; 2) That at least three
consecutive areas cannot differ between themselves regarding FWHM values for each
RD. It was considered that the REA, for distribution, was reached at the 8% RD. The
REA found for the GF, RF and EN soils were respectively: 555.4, 596.5 and 596.5 mm²
(scheme 1); 334.0, 457.4 and 457.4 mm² (scheme 2) and 526.4, 526.4 and 526.4 mm²
(scheme 3). Regarding scheme 1, the 8% RD was reached for 100%, 83% and 100% of
the GF, RF and EN soil samples, respectively. For scheme 3, REA was reached by 83% of
the soil samples. For scheme 2, only 67%, 33% and 67% of the soil samples listed above
reached REA. It was observed that regardless of the area selection scheme, the
distribution REA for GF (sandy texture) was lower than or even equal to that estimated in
RF and EN (clayey textures).
Keywords: Image
measurements.
analysis;
soil
structure;
soil
porous
system;
representative
14
DEVELOPMENT OF AN EQUIPMENT AND A DATA ACQUISITION SYSTEM FOR THE
DETERMINATION OF THE SOIL PERMEABILITY TO AIR
Figueiredo, C. C1., Armindo, R. A2., Silva, E. T2.
1
Master student of Soil Science Post Graduation Program - Federal University of Paraná (UFPR), e-mail: cerasomma@hotmail.com.
professors of Federal University of Paraná (UFPR).
2
Soil permeability to air (Kar) is an important physical property that allows to evaluate soil
quality and structure. In literature only a few studies report the development of equipment
for its determination. We aimed to develop a prototype equipment for the determination of
Kar in laboratory, taking advantage of the use of undisturbed samples of soil. To develop
the equipment, a differential pressure transducer and a temperature sensor were used,
both connected to a microcontroller. A software was developed to manage the monitored
data. The undisturbed samples of a very clayey and a sandy loam soil were submitted to
determination of Kar in the prototype, at several water contents. For the sandy loam
sample, Kar ranged from 0.6295 to 1.5269 mm s-1 in the water content interval between
0.4289 and 0.3308 m3 m-3. For the very clayey sample, Kar ranged from 0.9784 to 2.3945
mm s-1 in the interval between 0.6543 to 0.5149 m 3 m-3. The obtained results show a
similar trend for both evaluated soil textures, showing in a first moment reliability of the
novel equipment and of the developed software.
Keywords: Soil aeration; soil physical quality; automation.
15
DIGITAL IMAGE PROCESSING APPLIED TO X-RAY MICROTOMOGRAPHY TO
INVESTIGATE POROUS SPACE AND WATER WITHIN SOIL SAMPLES
Tseng Chien Ling1, Rodrigo Henrique Gounella2, Marlene Cristina Alves3, Carlos Manoel
Pedro Vaz4, Silvio Crestana4
1
Universidade de São Paulo (USP), chienlt86@gmail.com. 2Universidade Federal de São Carlos (UFSCar), rodrigorhg@gmail.com.
Universidade Estadual Paulista “Júlio Mesquita Filho” (UNESP), mcalves@agr.feis.unesp.br. 4Empresa Brasileira de Pesquisa
Agropecuária (Embrapa), carlos.vaz@embrapa.br, silvio.crestana@embrapa.br
3
The study of tropical soils under unsaturated conditions is essential to manage natural
resources, mainly soils and water, dealing to increase crop productivity, optimize inputs
and reach environmental sustainability. The aim of this study is to show the efficiency of
digital image processing to evaluate unsaturated soil images obtained through x-ray
microtomography. First of all, undisturbed and deformed soil samples were collected
around the Usina Hidrelétrica de Ilha Solteira (São Paulo State - Brazil) and pastures in
Mato Grosso do Sul State. For this experiment the samples were collected in three areas
with different land uses: A native vegetation (Cerrado), a pasture recovered with green
manure and a degraded pasture. Tomographic projections of undisturbed soil samples
were obtained by a microtomograph (Bruker, model 1172). The NRCon software was
employed to reconstruct, in two-dimensions, the tomography images. After that ImageJ
and CT-Analyser software were used to characterize the physical properties of the soil
samples. The deformed samples were employed to obtain the soil grain size distribution.
In conclusion, the digital image processing applied to the X-rays CT images allowed to
measure: 1) The solid, gas and liquid phases for each sample. 2) The soil samples
physical properties. As a consequence it was possible to assess the appropriateness of
the management utilized to recover the degraded areas.
Keywords: X-ray tomography; digital image processing; physical properties; recovery
techniques.
16
EFFECT OF BIOCHAR ON THE WATER HOLDING CAPACITY OF THE BRAZILIAN
SOILS EXEMPLIFIED BY SANDY NORTHEAST SOIL
Estela M. C. Cardoso1*, Marta E. Doumer1, Juliana Shultz1, Antonio S. Mangrich1,2,
Luciane P. C. Romão2 e Etelvino H. Novotny3
1
Department of Chemistry, Federal University of Paraná, UFPR, 81531-980 Curitiba, PR, Brazil. *estelamcc@gmail.com; 2Department
of Chemistry, Federal University of Sergipe, 49100-000, São Cristóvão, SE, Brazil. 3Embrapa Soils, Jardim Botânico, 22460-000, Rio de
Janeiro, RJ, Brazil.
The northeastern of Brazil is a semi-arid region has with a dry and warm climate with rains
that are concentrated between February and May. This bad distribution of rainfall over
time, combined with intense insolation, results in: a lower soil water retention capacity;
water infiltration to a deeper soil levels; rapid evaporation; and deficiency of water during
the main part rest of the year. In this work, we propose the use of soil organic conditioners,
derived from agricultural and industrial biomass wastes, in order to improve soil water
holding capacity (WHC). Five biochars, prepared by slow pyrolysis at low temperature
(heating to 350 °C at 5 °C min-1), were produced from green coconut shells (CS), orange
peel (OP), palm oil bunch (PO), sugarcane bagasse (SB), and water hyacinth plants (WH).
Charcoal fines, known as coal residue (CR), obtained from the metallurgical industry was
another studied sample. The soil investigated was dystrophic podzols, denoted as PD,
collected in the Reserva do Caju – Campus Experimental Embrapa Itaporanga, Sergipe,
Brazil. The treatments were 5% (w/w, equivalent to a biochar rate of 120 Mg ha-1) of each
biochar and a control without biochar. The WHC was determined by wetting/drying cycles
(Case et al., 2012). This application rate was calculated assuming 12 cm of soil depth and
bulk density of 1.2 g cm3. The soil-biochar mixtures were placed in PVC tubes (W = 50
mm; H = 75 mm). Then the mixtures were saturated with water for one hour, allowed to
drain for three hours in a sealed plastic buckets and subsequently dried in an oven (~60
°C). All the biochars increased the WHC, compared to the control. The biochars that
provided the best water retention were CS, PO, WH e SB (increases of 41, 41, 41 and 47
%, respectively). These results could be explained by the polarity of the biochars, as
shown by their hydrophilicity, measured by 13C NMR spectroscopy, as well as by the
increased presence of micropores that could physically retain water (revealed by SEM
analyses). The use of biochars could therefore contribute to alleviating hydric stress in
semi-arid regions of Brazil.
Keywords: Biochar; drying-wetting cycles; WHC; semi-arid.
17
EFFECTS OF SOIL COMPACTION IN DEVELOPMENT CORN ROOT
Maria de Fátima Marchezan Menezes da Silva1, Jéssica Pedroso Rosado1, Wildon
Panziera1, Ledemar Carlos Vahl2, Cláudia Liane Rodrigues de Lima2
1
Student, Postgraduate Program in Management and Conservation of Soil and Water, UFPel, mfmarchezan@gmail.com; 2Professor,
UFPel
The compaction process is mainly due to machinery traffic and animal trampling, which are
the main limitations of productivity of crops with economic importance to the country. The
bulk density (BD) is the indicator most frequently used in the evaluation of soil compaction
and indication of limitation for root growth. Thus, this study aimed to evaluate the effect of
soil compaction on root growth of maize by BD. An experiment was conducted in pots in
the greenhouse at the Federal University of Pelotas, the municipal district of Capão do
Leão, RS. The soil has a sandy loam texture and was collected from the surface layer
(from 0.00 to 0.20 m) of a Red Ultisol Yellow dystrophic. All treatments were soil core PVC
with a diameter of 0.0347 m and height of 0.0510 m, installed in vessels with 12 dm 3 of
soil, in which 10 were grown maize plants (Zea mays). In each pot were randomly
distributed six rings to 0.10 m under the surface. In each ring was set a level of BD (1.02;
1.17; 1.32; 1.48; 1.63; 1.78 Mg m-3). To obtain these levels of BD, the rings were filled with
sieved soil 2 mm mesh, varying the mass of soil placed in each ring. The vessels were
distributed in the greenhouse according to the experimental design of randomized blocks
with five replications. Gravimetric moisture in the ring was maintained at 20% by daily
addition of water. After 41 days of the emergence of the plants shoots, they were
harvested and able to remove the rings of the vessels to make the following
determinations: root length (L), dry weight of roots in each ring (Dw) and root length
density (Ld). The L was determined by Tennant method. The Ld was calculated taking into
account the length of the root, that is, the number of units of length in a given volume of
soil. The Ld and Dw roots increased with BD to around 1.3 Mg m -3 and then decreased
exponentially with BD bigger than this. This means that for the sandy loam soil studied
there is a BD range more suitable for the growth of roots around the value 1.3 Mg m-3.
Keywords: Zea mays; bulk density; root system.
18
EFFECTS OF SURFACE APPLICATION OF GYPSUM IN THE SOIL PHYSICAL
PROPERTIES AND YIELD OF CORN INTERCROPPED WITH JACK BEAN (Canavalia
eusiformis)
SEIDEL, E. P1; REIS, W. dos2; MOTTIN, M.C3.
1
DSc Prof. of State University of West Paraná, city of Marechal C. Rondon/Paraná/Brazil. edleusa.seidel@unioeste.br.
Agronomy and Scientific initiation follow. 3 Master in Plant Production, Unioeste.
2
Academic
The low Ca2+ concentration and toxicity Al3+ are limiting the productivity of the main crops,
and the use of gypsum agricultural is an alternative to solve this problem, moreover, the
use of gypsum can modify the physical properties of the soil. The study aimed to evaluate
the effect of surface application of gypsum in the soil physical properties and yield of corn
intercropped with jack bean (Canavalia eusiformis). The experiment was carried out on
Oxisols clay texture, from Marechal C. Rondon, Paraná State. The experimental design
was completely randomized blocks, arranged in a split plot design with four replications.
Plots consisted of corn with and without mixed cropping, and subplots were six rates of
gypsum (0, 1, 2, 3, 4, 5 t ha-¹), applied on the soil surface. Corn was sown in no-tillage
system, and the jack bean was sown manually in inter row. After corn harvest, undisturbed
soil samples were collected at depths of 0.0-0.05; 0.05-0.10 and 0.10-0.15 m to evaluate:
macro, micro, total porosity, soil bulk density. Soil penetration to resistance (PR) was
measured by the impact penetrometer, model Stolf to depth of 0.40 m. There was no
significant effect of gypsum rates and mixed cropping for grain yield. There were effects of
intercropping and rates of gypsum in soil physical properties. Soil at treatment with
intercropping corn had the highest macroporosity (0.087 m 3m-3) and total porosity (0.53 m3
m-3); and lower soil penetration to resistance at all depths. According to regression
analysis there was a quadratic effect of gypsum rates on PR. The major PR (4.06 MPa)
was obtained with at treatment without mixed cropping application, with application of 1.1 t
ha-1 gypsum.
Key-words: production system; soil penetration to resistance; calcium sulfate.
19
EMPIRIC MODEL FOR THE PREDICTION OF CAPILLARY RISE OF WATER,
GASOLINE AND DIESEL OIL IN SOIL
Robson André Armindo1, Clayton Cerasomma Figueiredo2, Letícia Gonçalves2
Professor of Department of Soil and Agricultural Engineering – Federal University of Paraná (UFPR). rarmindo@ufpr.br . 2Master
students of Soil Science Post Graduation Program – UFPR.
1
Some liquid pollutants occasionally, or purposely, can be in direct contact with soil. Thus,
the movement study of these liquids in the porous media becomes indispensable for an
appropriate environmental management. Notably, when water is placed in a container with
a tube of small radius, capillary rise is observed from its surface to a certain final height
(h). This height h can be calculated by the capillary equation h=2cos()/rg, which
depends on the surface tension coefficient (), gravity acceleration (g), radius of the
capillary tube (r), specific gravity () and contact angle between the meniscus of the
water-air interface (). When  ranges between 90 and 270º, cos()<1, resulting in
capillary depression, for example with mercury. Especially in soils with considerable clay
content, capillary rise can be considerable. A porous media system can be considered as
a bundle of capillary tubes, however it is known that it is not continuous system. We
developed a physical theoretical model to predict capillary rise of some liquids applied in
soils. Some analysis with a clay soil with 30, 23 and 47% of sand, silt and clay,
respectively, and bulk densities of 1200, 1300 e 1400 kg/m3 were realized with water,
gasoline and diesel observing their capillary rise in columns of 0,3 m of height. The
average particle density of the used soil was 2542 kg/m 3. The empirical model proposed,
that was compared to the experimental results is hL=[ssn/((-i))].t, where hL is the
capillary rise height of the liquid (m), ss is the soil dry bulk density (kg/m3),  is the
dynamic viscosity of the liquid (kg/m.s),  is the soil porosity (m3/m3), i is the volumetric
water content (m3/m3), t is the time for each hL value (s) and n is the empiric coefficient of
soil type. For water capillary rise, values of coefficient n were -1.91, -1.89 and -1.86 with
r=0.9965 and RMSE=0.0189m, r=0.9977 and RMSE=0.0111, r=0.9888 and
RMSE=0.0144m. For gasoline capillary rise, results of coefficient n were -1.98, -1.98 and 1.95 with r=0.9930 and RMSE=0.0200m, r=0.9922 and RMSE=0.0238, r=0.9900 and
RMSE=0.0185m were obtained. For diesel, the values of coefficient n were -1.90, -1.83
and -1.76 with r=0.9652 and RMSE=0.0991m, r=0.9638 and RMSE=0.0978, r=0.9793 and
RMSE=0.0297m. In conclusion, the theoretical model can be used to predict the capillary
rise of water, gasoline and diesel oil since 0 to 0,3m of height in clay soils, requiring more
tests to determine the coefficient n to other texture of soil and with columns of upper
height.
Keywords: Fuel movement in soil; infiltration; capillarity.
20
ESTIMATING BULK DENSITY FOR CALCULATING CARBON STOCK IN DIFFERENT
BRAZILIAN AGROECOSYSTEMS
Raquel Stucchi Boschi1, Maria Leonor Lopes-Assad2, Gabriela P. S. Souza2, Ana C. M.
Cidin2, Eduardo Delgado Assad1
1
Embrapa Agriculture Informatics,
(raboschi@gmail.com).
2
Center of Agricultural Sciences, Federal Univ. of São Carlos. *Corresponding author
In the context of climate change, the interest of estimating and monitoring soil organic
carbon (SOC) stock increased due to the importance of soil as organic carbon reservoir. In
recent years, the Brazilian government has proposed public policies aiming to promote
low-emission agriculture practices that require the knowledge of SOC stock. Estimates of
SOC stocks depend on the availability of soil bulk density (BD) used for weight-to-volume
conversion. Direct measure of BD is considering labor-intensive, time-consuming,
expensive, and often impracticable, especially when it involves a large number of samples.
As a result, BD measurements are frequently missing from soil databases. Thus,
pedotransfer functions (PTFs) have been developed to predict BD from more easily
available data. The objective of this study was to develop pedotransfer functions to
estimate bulk density from readily available soil data and evaluate the effect of the results
on the SOC stock of Brazilian agricultural soils. A data set of 974 samples was randomly
divided, and 12 PTFs were developed (75% of the data) and tested (25% of the data). The
developed PTFs are simple, user-friendly and can be applied by non-specialized users.
The performance of the PTFs was assessed by the coefficient of determination (R2), and
in the validation the accuracy of prediction was measured based on the mean error (ME),
the mean absolute error (MAE), and the root mean squared error (RMSE). All pedotransfer
functions overestimated BD values, but the PTF5 (DS=1.112+(0.0002913Sand)(0.007817CO)-(0.0002217Clay)+(0.06125pHH2O)) presented the best performance, given
the higher value of R2 (0.59) and the smaller values of MAE (0.13 g cm -3) and RMSE (0.18
g cm-3). In the soil carbon stock estimates, four PTFs (5, 6, 7 and 10) had low values of
MAE (~6 t ha-1), and RMSE (~11 t ha-1): PTF5; PTF6 (logDS=0.0494+(0.00032Sand)(0.0959CO)-(0.0000205Clay)+(0.06428pHH2O));
PTF7
(DS=1.123+(0.00037Sand)(0.12logCO)-(0.0000877Clay)+(0.076pHH2O); PTF10 (DS=1.8515+(0.18856 logCO). Thus,
the values of errors in soil carbon stock estimates were close. We conclude that the errors
found in the estimates of bulk density by means of pedotransfer functions are not
necessarily propagated in the estimate of soil carbon stock.
Keywords: Pedotransfer functions; soil data set; pedometrics; tropical soil.
21
ESTIMATING LEACHATE GENERATION BY A LANDFILL USING THE HYDRUS
CODES
Kymie Saito1, Martinus Th. van Genuchten1,2, Otto C. Rotunno Filho1, and Webe J.
Mansur1
1
Department of Civil Engineering, Federal University of Rio de Janeiro, COPPE, Rio de Janeiro, Brazil kymiesaito@gmail.com,
2
ottorotunno@oi.com.br,
webe@coc.ufrj.br)
Department
of
Earth
Sciences,
Utrecht
University,
Netherlands
(rvangenuchten@hotmail.com).
Effective management of municipal solid waste (MSW) landfills requires proper
understanding of the processes controlling the infiltration of water into the landfill and the
generation of leachate. Especially important is limiting the environmental impacts of
landfills by controlling leachate formed by the infiltration water and its interactions with the
waste. The objective of this study was to estimate the long-term cumulative rates of
infiltration, evaporation, transpiration, runoff and drainage for an existing landfill in the city
of Nova Iguaçu near Rio de Janeiro, Brazil. A series of one- and two-dimensional
numerical calculations were carried out for a period of 20 years using the HYDRUS-1D
and HYDRUS 2/3D software packages. Soil and waste hydraulic parameters were
established based on literature data and the physical properties of local soils. We obtained
snapshots of simulated contaminant plumes within the landfill, as well as estimates of the
amount of leachate generated by the landfill, including its contaminants. A sensitivity
analysis showed the important effects of the physical makeup of the landfill cover,
including the presence of geomembranes and capillary barriers, and the use of native
vegetation or grass on the cover. The numerical studies were found to be very useful for
studying water flow and contaminant transport processes within and from the landfill, and
possible risks of polluting nearly soil and water resources.
Keywords: Municipal solid waste; leachate; landfill; HYDRUS; soil contamination
22
EVALUATION OF DIFFERENT PARAMETERIZATIONS FOR THE VAN GENUCHTEN
SOIL WATER RETENTION FUNCTION
Marta V. Ottoni1,4, Theophilo B. Ottoni Filho2, Martinus Th. van Genuchten3 and Otto C.
Rotunno Filho4
1
Department of Hydrology, Geological Survey of Brazil (CPRM), Rio de Janeiro, RJ, Brazil. corresponding author:
marta.ottoni@cprm.gov.br. 2Department of Water Resources and Environment, Federal University of Rio de Janeiro (UFRJ), Rio de
Janeiro, RJ, Brazil. 3Department of Mechanical Engineering, COPPE/LTTC, Federal University of Rio de Janeiro (UFRJ), Rio de
Janeiro, RJ, Brazil. 4Civil Engineering Program/COPPE, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
The van Genuchten (VG) equation is often used to describe soil water retention (WR) data
relating the water content (θ) with suction (s). The model is commonly implemented with
four independent parameters, i.e., α, n, θr, and θs. Many applications use only three
parameters (α, n, θr), which has some advantages such as minimizing possible correlation
among the parameters and simplifying inverse methods for estimating the parameters. The
two VG parametrizations are usually applied to a large number of experimental WR data
points that cover a broad range of suctions. Experimentally this is very time consuming
and expensive. The objective of this study was to compare the performance of the VG
parameterization using only three parameters and only three data points with more
detailed descriptions in terms of a larger number of retention parameters and experimental
data points. We selected for this purpose 1565 undisturbed soil samples from Brazil and
Europe, with each data set containing at least five WR measurements covering a wide
range of suctions (0-15,000 cm). Four different cases were studied. For Cases 1 and 2 we
optimized three parameters (α, n, θr) by assuming the saturated water content (θs) to be
known, whereas for Cases 3 and 4 we considered all four parameters (α, n, θr, θs). For
Cases 1 and 4 we used only three unsaturated data points, plus the measured θs value,
while for Cases 2 and 3 we used all available WR data. The three unsaturated WR data
points of Cases 1 and 4 were the data at suctions closest to 60, 330 and 15,000 cm.
Results showed that the corresponding WR estimates calculated for Cases 1 to 4 had no
statistical differences between them for suctions above 30 cm (using the paired t-test), at a
high probability level (p>~0.50). In general, the four configurations were able to describe
water contents accurately within this suction range, with global RMSE (root mean squared)
values varying from 0.011 cm3cm-3 (Case 3) to 0.014 cm3cm-3 (Case 1). On the other
hand, in the wet range for suctions less than 30 cm, the fitted θ-values did not compare
well, with Case 3 providing the most accurate estimates in this range and Cases 1 and 4
the least accurate. We conclude that using only three experimental points (at the s-values
we used) to fit the three parameters of the VG equation is justified when representing
water content data in the dry range for suctions above 30 cm. However, we do not
recommend this configuration when the entire suction range from saturation to 15000 cm
is of interest, in which case Cases 2 and 3 should be used. Case 3, furthermore, has the
disadvantage of estimating water content very close to saturation with larger errors than
when θs is fixed (Case 2).
Keywords: van Genuchten equation; water retention curve; soil database.
23
EVALUATION OF TWO DIFFERENT CONSTANT-HEAD CONTROLLER UNITS OF
AUTOMATIC PERMEAMETER (PA-LHG) FOR IN SITU MEASUREMENT OF FIELDSATURATED HYDRAULIC CONDUCTIVITY
Lange, D. R.1, Santos, I.2;
1
Laboratório de Hidrogeomorfologia (LHG-UFPR) E-mail: ribeirolange@gmail.com. 2Laboratório de Hidrogeomorfologia (LHG-UFPR) Email: irani69@gmail.com
The automatic constant-head permeameter (PA–LHG) was developed based on Guelph
Permeameter models and the permeameter of the Instituto Agronômico de Campinas
(IAC). The apparatus is used to measure in situ field-saturated hydraulic conductivity (kfs).
The PA-LHG consists of a reservoir, which functions based on the Mariotte principle, a
constant-head controller unit, which controls water supply and maintains a constant head
inside the well, and an adjustable tripod. Water level readings in the reservoir are
automatic, using a pressure transducer (MPXV7007DP), and data is stored in a
datalogger. In this paper, we evaluate the performance of two different models of constanthead controller units developed for the PA-LHG, called model P1 and P2. Model P1 has
two hoses, one responsible for water supply and the other for air exchange between the
atmosphere and the interior of the reservoir. Model P2 has only one hose used
simultaneously for air exchange and water supply. To evaluate the constant-head
controller units, we assessed the ability of the model to stabilize in pit water level during
the test, as well as water level oscillation in the interior of the reservoir. Model P1
presented better performance for the apparatus, with lower well-water oscillation levels
than for P2. Water level downgrade rate variations in the interior of the reservoir were also
lower for P1. The features used in P1 allowed PA-LHG to effectively determinate fieldsaturated hydraulic conductivity and to obtain useable data on the soil layer being studied.
The automatic constant-head permeameter (PA–LHG) presents consistent results and is a
low cost alternative to other equipment available on the market.
Keywords: Field-saturated hydraulic conductivity; constant head permeameter; in situ
measurements.
24
FORECASTING CROP EVAPOTRANSPIRATION FROM ENSEMBLE-BASED
NUMERICAL WEATHER FORECASTS AND HIGH RESOLUTION SATELLITE IMAGES
Hanoi Medina González 1, Anna Pelosi2, Paolo Villani2, Guido D’Urso3, Salvatore Falanga
Bolognesi4, Giovanni Battista Chirico5
1
Department of Basic Sciences, Agrarian University of Havana, 32700, La Habana, Cuba; 2CUGRI, Salerno University Campus, 84084
Fisciano (SA), Italy; 3Department of Agriculture, University of Naples Federico II, 80055 Portici (NA); 4Ariespace s.r.l., 80143 Napoli,
Italy. Email: hanoimedina@gmail.com
The increasing availability of remotely sensed information and the wide access to the new
technologies provide unprecedented opportunities to support management, monitoring and
controlling of agricultural activities as crop irrigation. However, due to the random nature of
weather and environmental conditions, water use by evapotranspiration tends to be highly
variable, which makes efficient irrigation scheduling a challenging task. Stochastic
methods dealing with weather and crop development uncertainties can be valuable tools
for implementing operational advisory irrigation services. The objective of this work is to
ponder the efficiency of a stochastic ensemble-based model for estimating and forecasting
crop potential evapotranspiration, implemented within an advisory service, with explicit
consideration of model, inputs and parameters errors. The stochastic model combines
estimates of crop potential evapotranspiration retrieved from ensemble numerical weather
forecasts (COSMO-LEPS, 16 members, 7 km resolution) and canopy parameters (LAI,
albedo, fractional vegetation cover) derived from high resolution satellite images in the
visible and near infrared wavelengths. A self-adaptive Kalman Filter strategy is utilized for
targeting to the local adaptation of the forecasted potential evapotranspiration and the
reduction of systematic biases. Retrieved remotely sensed LAI products are assimilated in
a detailed crop model that simulates the crop growth dynamics. The model has been
implemented in an advisory service providing users with daily estimates of crop water
requirements for lead times up to five days. The model has been applied in Campania
region (Southern Italy), where a satellite assisted irrigation advisory service has been
operating since 2006. The results of the system performance for two years of experimental
service under maize cultivation suggest that the proposed model can be an effective tool
for agricultural water management under conditions of water scarcity and drought.
Keywords: Irrigation; leaf area index; Kalman filter; stochastic methods; remote sensing.
25
GRANULOMETRIC ANALYSES OF SOME SANDY SOILS FORM NORTHERN MINAS
GERAIS
João Herbert Moreira Viana1, Guilheme Kangussu Donagemma2
joao.herbert@embrapa.br; Embrapa Milho e Sorgo, Sete Lagoas – MG, Brazil. 2Guilheme.donagemma@embrapa.br Embrapa Solos,
Rio de Janeiro – RJ, Brazil
1
The granulometric distribution curve is one of the most basic and important characteristics
of the soils, and it is directly related to many soil functions, e.g. gas and water permeability
and retention. As the granulometric analysis is one of the standard routine analyses for
soils, and it is usually available in the soils data bases, it has been used as a proxy for
other parameters that are less available, more difficult or more expensive to achieve,
through the pedotransfer functions (PTFs), such as the retention curve. The goal of this
work is to model and to evaluate the distribution curves of some representative sandy soils
of northern Minas Gerais, developed over the Urucuia Sandstone Formation, which have
been used for rain fed agriculture, and to establish a general model curve for these soils,
to be used in modelling and in comparative analyses. Eight soils (48 horizons in total) were
analyzed, ranging from sandy to sandy-clay-loam texture. The granulometric analysis was
performed accordingly to Brazilian standards, and the sand fraction was partitioned in five
size classes. The cumulative distribution curves were computed and empiric non-linear
functions were fitted to them. The curves were fitted for each soil horizon, and also for the
whole profiles. The results indicate that the fitting procedures were efficient, but different
models were necessary for the profiles. In some cases, even in the same profile different
models were applied. The Morgan-Mercer-Flodin (MMF) model was the best for half of the
horizons, followed by the Weibull Model (33%) and the Logistic model (13%). Only for two
horizons the Richards model was the best. The MMF model was also the most flexible,
adapting to soils of broad granulometric distribution, from sandy to sandy-clay-loam. The
Weibull model performed best in the sandy-clay-loam soils, and the Logistic model in the
sandy soils.
Keywords: Sand analysis; soil modelling; soil physics.
26
INFLUENCE OF WINTER COVER CROPS ON PHYSICAL PROPERTIES OF THE SOIL
Mottin, M.C.1, Seidel, E.P.2, Fey, E. 2; Richart, A. 3, Vanelli, J. 1; Alves, A.L. 1, Schneider,
A.P.H. 4, Sustakowski, M. 4
1
Student, Graduate Agronomy Program, UNIOESTE. E-mail: marcos.c.mottin@hotmail.com; 2Faculty member, UNIOESTE. E-mail:
edleusa.seidel@unioeste.br; 3Faculty member, PUCPR. E-mail: alfredo.richart@pucpr.br; 4Undegraduate student, Agronomy,
UNIOESTE. E-mail: anapaulahecksh@hotmail.com
The objective of this work was to evaluate the influence of winter cover crops on the
physical properties of a Eutrophic Red Latosol. The study was carried out at the
experimental station of Western Paraná State University (UNIOESTE) located in the
municipality of Entre Rios do Oeste-PR. The soil in the experimental unit was classified as
Eutrophic Red Latosol, with very clayey texture. The experimental design used was
randomized blocks, with six replications. Plots consisted of four winter cover crops; two of
which were Poaceae (bristle oat and brachiaria) and two Fabaceae (field pea and white
lupine). The winter crops were sown mechanically using a plot seeder, at 70 kg ha -1 for
bristle oat (Avena strigosa S.); 8 kg ha-1 for brachiaria (Urochloa ruziziensis); 60 kg ha-1 for
field pea (Pisum sativum L.) and 50 kg ha-1 for white lupine (Lupinus albus L.), without the
use of basic fertilizer; row spacing was 0.20 m for Poaceae and 0.40 m for Fabaceae. At
120 days, the cover crops were managed using Glyphosate at 3 kg ha-1 of acid equivalent.
After 20 days of cover crop management, the study evaluated macroporosity,
microporosity, total porosity, soil density and soil resistance to penetration (RP). Results
showed that macroporosity, microporosity, total porosity, soil density and RP were
influenced by the cover crops. The treatments using bristle oat and Urochloa ruziziensis
afforded the highest macroporosity (0.13 m3 m3), as well as the lowest microporosity (0.40
m3 m3). Soil density showed significant differences for field pea (1.33 kg dm -3) and bristle
oat (1.22 kg dm-3), and the cover crops did not influence soil total porosity. With regard to
RP, white lupine showed the highest values as cover crop at the layers between 0.10 and
0.20 m, reaching values ranging from 1.00 to 1.87 MPa.
Keywords: Adubação verde; sucessão de cultura; macroporosity, soil resistance to
penetration.
27
MODELLING THE WATER FLUX IN A RHODIC EUTRUDOX UNDER TILLAGE
SYSTEMS
Moacir Tuzzin de Moraes1, Henrique Debiasi2, Michael Mazurana3, Julio Cezar Franchini2,
José Antônio Louzada4, Renato Levien3
1
Doctoral student, Post-Graduation course in Soil Science, Federal University of Rio Grande do Sul - UFRGS. Av. Bento Gonçalves,
7712, Prédio 41506. CEP 91540-000 Porto Alegre (RS), Brazil. E-mail: moacir.tuzzin@gmail.com. 2Researcher, Embrapa Soja. Rod.
Carlos João Strass, Distrito de Warta. Caixa Postal 231. CEP 86001-970 Londrina (PR), Brazil. 3Professor Associate, Department of
Soil Science, UFRGS. Av. Bento Gonçalves, 7712. Prédio 41506, CEP 91540-000. Porto Alegre (RS), Brazil. 4Department of Hydraulic
Works, Institute of Hydraulic Research, UFRGS. Av. Bento Gonçalves, 9500, CEP 91501-970, Porto Alegre (RS).
Soil water dynamics is one of the main factors affecting water-limited productivity of
agricultural crops. An important tool in modelling soil water dynamics is the Soil Water
Atmosphere Plant (SWAP) model. We aimed to study the water dynamics in a Rhodic
Eutrudox with different long-term soil tillage systems using the agrohydrological model
SWAP. The flux of water in a layer of soil ranging from 0.0 to 0.5 m was simulated for
three different soil tillage systems (no-tillage, reduced tillage with annual chiseling and
conventional tillage). Agro-meteorological data from January 2001 to November 2013 were
used. The profile water depth was affected by the tillage system. Conventional tillage
increased periods with low water availability to the crops. Throughout time, both no-tillage
and reduced tillage showed suitable water availability. No-tillage showed smaller
superficial flow rates, promoting the increase in water storage and deep drainage.
Conventional tillage promoted the increase in superficial flow rates and reduction of deep
percolation through soil, reducing the profile water storage and increasing the number of
days in which the water content in soil remains below a critical available fraction of water
(0.5).
Keywords: SWAP; no-tillage; tillage systems; soil water dynamics.
28
MODELS OF WATER MANAGEMENT UNITS FROM THE SPATIAL VARIABILITY OF
PHYSICAL AND HYDRAULIC SOIL PROPERTIES
Silva, B. K1., Armindo, R. A.2, Sobenko, L. R.3, Ceresoli, L. L.4
Master’s student of the Soil Science Post Graduation Program – Federal University of Paraná (UFPR), brianekreitlov@yahoo.com.br;
Professor of the Department of Soils and Agricultural Engineering – UFPR; 3Master’s student of the Agricultural Systems Engineering Luiz de Queiroz College of Agriculture (ESALQ); 4Agronomy Student of UFPR.
1
2
Soil physical attributes have direct influence in several aspects like root growth,
agricultural production, management and conservation of soil, hydrological and irrigation
studies. This work aimed to analyze the spatial variability of physical and hydraulic
properties of soils and the corn crop evapotranspiration in an area that would be irrigated
by center pivot. Analysis of sand, silt, clay, soil bulk density (ρs) and particles (ρp), total
porosity (α) and aeration porosity (αar), saturated hydraulic conductivity (K), water
retention, available water capacity (AWC) and easily available water (EAW) were done.
Samples for ρs, ρp, α and αar were collected at regular grid of 50x50m and 40x40m to K,
resulting in 33 average values from three replicates for ρp, α, sand, silt, clay, AWC, EAW
and αar variables, 57 for ρs variable and 24 to K variable. With results obtained in the
laboratory, it was used package geoR, from software R, for geostatistical analysis that
allowed the development of water levels management unit models to apply on the study
area. It was observed spatial dependence between physical and hydraulic attributes
evaluated. With the values of Akaike Information Criterion (AIC) and Bayesien Information
Criterion (BIC) were chosen models for the realization of thematic maps. Such models
were: Gaussian for ρp, α, sand, K and αar variables; Exponential for silt, Family Matern
(kappa = 1.5) for clay; Matern Family (kappa = 2.5) for AWC and EAW; Spherical for ρs
variable. Therefore, the theoretical range obtained for the variables ρp, α, sand, silt, clay,
CAD, K, ρs, αar and EAW were 64, 226, 648, 114467, 1884, 934, 55, 44, 195 and 944m,
respectively . The water depth maps generated from the proposed models allow more
rational use of water resources in order to provide an adequate physical soil management.
Keywords: Geostatistics; avaliable water capacity; management zone.
29
PERFORMANCE OF SPLINTEX PROGRAM ON SOIL WATER RETENTION CURVE
PREDICTION CONSIDERING THE ABSENT OF WATER CONTENT MEASUREMENTS
Reis, A.M.H1, Armindo, R.A2, Durães, M.F. 2
1
Undergraduate Student- Federal University of Paraná-UFPR, tutiufpr@gmail.com.
Engineering – UFPR.
2
Professor Department of Soils and Agricultural
Currently, one of the most important tools for agricultural projects is the determination of
the soil water retention curve (SWRC). This information allows to evaluate the physical soil
quality, the soil-plant-atmosphere system, the water dynamics in the soil, besides being
useful in designing irrigation and drainage projects. The SWRC is the inverse relationship
between water content and the matric potential. Among the direct methods stand out
Richards chamber, Haines funnel, tension table, centrifuge, filter paper and other can be
used to its determination. However, these methods demand time processing.. Therefore,
indirect methods of determining the SWRC have been developed. Among the indirect
methods, there are the pedotransfer functions. This study aimed to evaluate the
pedotransfer program SPLINTEX, estimating soil hydraulic parameters from the geometry
and particle size distribution, soil density, particle density and moisture saturation, taking
advantage of the Arya-Paris model and cubic spline function. It was used a data bank from
the literature with several works that had granulometric and parametric data retention
curve in order to compare with the results obtained by SPLINTEX. The analysis were
carried out with and without experimental point knowledge of the SWRC. The SPLINTEX
demonstrated better functionality in determining the parameters in wet part of the SWRC.
The α parameter presented uncertainties in adjusting, but has acceptable average error.
The n parameter also showed low coeficients of determination, justifying probably the
influence of soil density.In general, the performance of the SWRC by SPLINTEX was
satisfactory when the experimental point is used and when the experimental point is not
informed by the user.
Keywords: Soil physics; simulation; hydraulic conductivity.
30
PERFORMANCE OF PEDOTRANSFER FUNCTIONS TO SIMULATION OF SPATIAL
VARIABILITY OF THE SOIL HYDRAULIC FUNCTIONS
Silva, A.C.1, Armindo, R.A.2, Brito, A.S.3, Silva, E.T.2
Master's student of the Soil Science Post Graduation Program – Federal University of Paraná (UFPR). email:
engalecalegari@gmail.com; 2 Professor of the Department of Soils and Agricultural Engineering - UFPR; 3 Professor of the Department
of Soils - Federal Institute of Education, Science and Technology – IFET Baiano.
1
The Knowledge of the soil hydraulic properties and their spatial variability is crucial in
hydrological and environmental studies. To provide this information spending less time and
resources, the estimation of the water retention and its movement, from easily measurable
soil data, has called more attention. This is an interesting application of a Pedotransfer
Functions (PTF). This study aimed to compare the observed spatial variability of a sandy
soil and its spatial variability simulated by two PTF's of parametric basis. The study was
carried out in an experimental area in College of Agriculture "Luiz de Queiroz" (ESALQUSP), Piracicaba city, São Paulo state, Brazil. In this area, 60 points of samples were
collected with regular spacing of 5 x 5m. All of these points were georeferenced, with s
disturbed and undisturbed soils samples that were collected in the layer depth of 0.750.85m. Texture (sand, silt and clay), soil porosity, bulk and particles densities, water field
capacity, permanent wilting point, available water capacity and hydraulic functions (soil
water retention curve, hydraulic conductivity, water specific capacity and hydraulic
diffusivity) were determined. It was found in the geostatistic analysis that some attributes
and hydraulic functions had spatial dependence and the data simulated by PTF’s
SPLINTEX and ROSETTA result in similar semivariograms with nugget, sill and ranges
values as well result in observed data. Although the quality of interpolation by kriging
based on simulated results had not the same behavior as observed results, the analysis of
the dependence showed spatial similarities among the results. It was concluded to
evaluated area that the use of PTF's in determining the spatial variability presented certain
precision requiring caution against their use in environmental studies.
Keywords: Geostatistics; soil moisture maps; soil water retention curve.
31
PHYSICAL ATTRIBUTES OF AN OXISOL WITH SOYBEAN CROP UNDER DIFFERENT
AGES IN PIAUIENSE CERRADO
Leovanio Rodrigues Barbosa1, Francisco Rafael Da Silva 2, Rolff Vladimir Mitton 3, Luís
Alfredo Pinheiro Leal Nunes 4
1
First Author is Agronomist Msc in Soil Science and Plant Nutrition and PhD Candidate in Soil Sciences at the Federal University of
Paraná (UFPR), Curitiba, PR. E-mail: leovaniobarbosa@hotmail.com (presenter of the work). 2Second Author Agricultural Engineering
Candidate of the Federal University of Piauí, Campus Minister Petronio Portela, Teresina - PI. 3Third author is Agronomist Engineer and
MSc Canditate in Soil Science at the Federal University of Paraná, Curitiba. 4Fourth Author is Associate teacher, UFPI, CCA, DEAS and
Soil Lab Coordinator, Campus Minister Petronio Portela, Teresina, PI.
The “Piauiense Cerrado” considered by many as the last agricultural frontier in Brazil, has
stood out on the national scene as a region of great potential for grain production,
especially with the soybean crop. However, the holding in these areas is still based on
management systems with intensive soil tillage, by plowing and harrowing, causing in the
process many changes in the soils’ physical properties. This study aims to understand the
effect of time on an Oxisoil cultivated with soybeans by taking under account the soil’s
physical attributes and quality. A preserved native “Cerrado forest” (used as the control in
the experiment) and three soybean planted areas: 1 (PC1), 3 (PC3), and 6 (PC6)
(corresponding to the respective years of use) were contemplated for this study. The study
was conducted at the Farm “Chapada Grande”, a district of “Regeneração” municipality, PI
(06°14'16"S, 42° 41'18"W). The soil, according to the Brazilian Soil Classification index for
the Piauí state, is an oxisoil. The management of cultivated areas has been carried out by
intensive conventional tillage. In each area four plots of 400 m 2 (20 x 20 m) were
established for soil sampling. In each plot 4 undisturbed samples for soil density (Ds)
determination were collected by using volumetric rings. The particle density (Dp) was
determined by volumetric flask method and the total porosity (Pt) was calculated by the
formula: E = (1 - Ds / Dp) x 100. The soil penetration resistance (RSP) was determined by
using an impact penetrometer (model IAA / Planalsucar – Stolf) through the penetration of
a shank into the ground from an impact weight in free fall at a height of 0.40 m. The results
indicate that longer land use, promotes changes in soil density and total porosity when
compared to the “Cerrado forest”. This is probably due to the intensive use of agricultural
machinery. From 0.15 m in areas with 3 and 6 years of use, the soil resistance to
penetration values was higher than 2.0 MPa, a restrictive threshold to the development of
roots. This suggests that practices that promote periodic disturbances of the soil increase
the density values and therefore, the soil resistance to penetration became more evident
over time.
Keywords: Physical attributes; degradation; conventional tillage.
32
PHYSICO-HYDRICAL ATTRIBUTES OF AN ALBAQUALF CULTIVATED UNDER
CONVENTIONAL TILLAGE AND NO-TILLAGE SYSTEMS
Bruno César Gurski1, Jorge Luiz Moretti de Souza1, Daniela Jerszurki1
1
Federal University of Paraná, Soil Science and Agricultural Engineering Department, Rua dos Funcionários, 1540, CEP 80035-050,
Curitiba, PR, Brazil. E-mail: brunogurski@ufpr.br; jmoretti@ufpr.br; djerszurki@ufpr.br.
The Pampa biome portion located in the Rio Grande do Sul State, Brazil has about 5.4
million hectares of lowlands. The recently introduction of rainfed crops associated with
surface drainage technologies has been diversifying the traditional rice-livestock
production system. The objective of this study was to evaluate the effect of tillage systems
on soil physico-hydrical attributes of an Albaqualf under conventional tillage and no-tillage
system. The study was carried out during a soybean crop cycle in two experiments
installed at the Lowland Experimental Station – Research Centre of Temperate
Agriculture, Capão do Leão, Rio Grande do Sul State, Brazil. The no-tillage system (NTS)
was installed in November 2006 while the conventional tillage (CT) was installed in
November 2013, after a fallow period of three years. Soil samples with undisturbed
structure were collected in the 0.00-0.10; 0.10-0.20 and 0.20-0.40 m soil layers to
determine the macroporosity (MA), microporosity (MI), total porosity (TP), bulk density
(BD) and soil water retention curve (SWRC) related attributes such as: water content at
field capacity (θFC), permanent wilting point (θPWP), and available water (AW). Matric
potential was monitored with soil sensors and water storage was calculated during the
soybean crop cycle. The experimental treatments were submitted to analysis of variance
and means were compared by Duncan test (p<0.05), using the software Statistical
Analyses System Institute. Both tillage systems showed MA smaller than 0.10 m 3 m-3,
posing limiting conditions for gas exchange and water infiltration, however, on NTS it was
observed higher values of MI in the 0.00-0.10 m soil layer and, in the 0.10-0.20 m soil
layer, it was found higher MA, TP associated with lower BD, indicating improvements in
soil structure when compared to CT, probably, due to the development of diversified root
systems, reduction of machine traffic and continuous supply of organic matter to the soil
surface. The θPWP was not affected by the soil tillage, but it was observed higher AW and
θFC in the 0.00-0.10 m soil layer of the NTS. According to the shape of the SWRC, NTS
promoted higher water retention capacity than CT in the 0.00-0.10 m soil layer, resulting in
more available water during the whole crop cycle. Considering the cultivation of rainfed
crops such as soybean in lowlands of the Pampa biome, apart from the management
system, the low MA mean values seem to be the main soil physical limitation, however, the
NTS was more effective to improve soil structure and use of water resources.
Key Words: No-tillage; Glycine Max (L.) Merr; soil porosity; available water capacity; soil
water storage.
33
PRESERVING HETEROGENEITY AND CONSISTENCY IN HYDROLOGICAL MODEL
INVERSIONS BY ADJUSTING PEDOTRANSFER FUNCTIONS
Marcel G. Schaap1, Yonggen Zhang1,2, Chi Xu2,3
1
Department of Soil, Water and Environmental Science, College of Agriculture and Life Sciences, University of Arizona, Tucson AZ,
USA mschaap@cals.arizona.edu 2 Department of Hydrology, College of Science, University of Arizona, Tucson AZ, USA 3 State Key
Laboratory of Water Resources and Hydropower Engineering Science. Wuhan University, China
Numerical modeling is the dominant method for quantifying water flow and the transport of
dissolved constituents in surface soils as well as the deeper vadose zone. While the fundamental
laws that govern the mechanics of the flow processes in terms of Richards' and convectiondispersion equations are relatively simple in principle, the practical implementation and
parametrization of realistic “problems” remains difficult and fraught with many uncertainties.
Besides defining appropriate boundary conditions (e.g., atmospheric forcing by rain and
evapotranspiration as well as groundwater fluctuations), the practitioner must decide upon the
dimensionality, space and time discretization and the internal structure of the problem (e.g.,
pedological structure and stratigraphy) and assign realistic hydraulic and chemical properties
(water retention and unsaturated hydraulic conductivities and absorption coefficients) to all
elements in the numerical grid. It is well-known that hydraulic properties are difficult to measure,
making it virtually impossible to completely cover the variability within the simulated domain.
Instead, inversion methods are often deployed which allows the determination of effective
parameters by optimizing hydraulic parameters on observed time-series of moisture contents or
matric potentials. Similar to laboratory measurements, field monitoring is expensive and problems
with non-uniqueness of the inversion results often limits the level of detail that can be resolved in
the subsurface. Without additional data or methods, lab measurements nor model inversions can
completely characterize all the heterogeneity present at a site and the resulting model may
therefore not be able to provide reliable flow estimates. Pedotransfer functions are an alternative
method for estimating hydraulic properties from “cheap” and ubiquitous co-variates such as soil
particle size and bulk density. The method is imperfect, however, because usually only
approximate relations can be established that are database or site-specific and which do often not
“transfer” accurately to other locations. In this presentation we will discuss a method that will allow
the preservation of heterogeneity by combining a 3D geostatistical model of texture and bulk
density at a deep vadose zone site, with a pedotransfer function and model inversion. Instead of
optimizing hydraulic parameters directly ('direct optimization'), the new method optimizes
parameters in simple functions that scale pedotransfer estimates for the 3D geostatistical model.
The new method has several advantages over typical inversion methods: 1) It does not require that
the pedotransfer (PTF) model is perfect. Instead, the method allows the PTF to be adjusted to
better represent the site. 2) It does not require that the site is sub-divided in homogeneous
subdomains. as is typical for direct inversion methods. We will show that sub-division is still
advisable, but that such sub-domains can retain their internal variability. 3) The new method leads
to better results than direct optimization of hydraulic parameters and is amenable to cases where
direct optimization is impossible (e.g. when data is sparse). The new method has a limited
number of free parameters, ensuring a quick convergence upon a final solution. We will also
present some further refinements regarding a previously published PTF (Rosetta). Rosetta was
previously optimized to predict van Genuchten-type (VG) hydraulic parameters without regarding
the uncertainty of the VG parameters when they were optimized on measured data. We show that
weighting by uncertainty improves the models performance (in terms of root mean square error)
and virtually eliminates model bias. The new model also allows the computation of a full
covariance matrix which is helpful for doing uncertainty analyses in numerical model simulations.
34
RELATIONSHIP OF SOIL PHYSICAL PARAMETERS WITH SORPTIVITY AND
HYDRAULIC CONDUCTIVITY
Adalberto Alves Pereira¹, Edivaldo Lopes Thomaz²
¹Geography doctoral student, State University of Ponta Grossa - UEPG, CAPES Scholarship, adalbertoalvespereira@yahoo.com.br.
²Prof. Dr. Geography department, University of the Midwest – UNICENTRO, ethomaz@brturbo.com.br
Understanding soil water dynamics in soil agricultural áreas is of great importance. Among
the parameters of importance for the involved processes are sorptivity (S) and hydraulic
conductivity (K). Sorptivity is the soil's ability to absorb capillary water in the absence of
gravitational effects, and predominates during the first moments of infiltration, whereas soil
hydraulic conductivity is the ease with which a fluid is transported throught the soil pore,
highest for saturated soil. In this essay we seek to evaluate the sorptivity and hydraulic
conductivity and their relation to physical parameters (density and mechanical resistance)
in a red-yellow Ultisol under different management conditions. Four areas were studied in
the Palmeirinha stream watershed, Reserva municipality, Paraná state. Identified follows:
PC - conventional tillage of black beans (Phaseolus vulgaris L.); PR - cultivated with black
beans for 30 years under reduced tillage system; PT - 10 years of management with
extensive grazing, and FT – native forest. Nine infiltration tests were performed on each
area using a tension disk infiltrometer with a diameter of 20 cm. Previous and final water
content was measured with a TDR probe. 12 undisturbed soil samples were collected in
each area at depths of 0-0.05; 0.05-0.15 and 0.15-0.30 m to measure bulk density. The
soil resistance was evaluated to a depth of 0.30 m with an impact penetrometer. Sorptivity
had greater influence on the movement of water in areas with a higher degree of
compaction, whereas in areas with lower density and soil resistance the hydraulic
conductivity was the most determining property. Soil compaction tends to reduce pore
diameters reducing the gravitational effect and increasing capillary forces explaining higher
sorptivity in the compacted areas. Multiple regression showed high correlation (R² >0,99)
among physical parameters and S and K, this correlation being positive for S and negative
for K. These results allowed to conclude that: a) density and mechanical resistance can be
used to estimate the sorptivity and hydraulic conductivity in the studied soil; b) in
compacted soil, sorptivity is the most determining property for water movement, whereas
hydraulic conductivity is more important in areas with lower density and mechanical
resistance. Further studies will be necessary to better understand soil water dynamics and
its relationships with soil physical properties.
Keywords: Soil water dynamics; infiltration, soil resistance.
35
RESILIENCE OF SOILS WITH DIFFERENT ORGANIC MATTER, TEXTURE AND
MINERALOGY IN LONG-TERM NO-TILLAGE SYSTEMS
J. A. Bonetti 1, 2, I. Anghinoni 1, M. T. Moraes 1 and J. R. Fink 1
1
Department of Soils, Federal University of Rio Grande do Sul, Bento Gonçalves Avenue, 7712, CP 91540-000, Porto Alegre, Rio
Grande do Sul, Brazil. 2Corresponding author. Tel.: +55 51 98255488. E-mail address: agro.bonetti@gmail.com
Soil conservation systems are important to mitigate soil degradation imposed by intensive
utilization in tropical and subtropical areas around the world. Originally Brazilian
subtropical soils are generally well structured and characterized by a high load bearing
capacity and recovery from anthropic action. However even so, intensive conventional
cultivation systems for many decades caused degradation on these soils. Physical
resilience attributes in subtropical soils with different organic matter content, texture and
mineralogy were explored in this paper. Intact and altered soil samples were collected in
two layers of three no-tillage long term field experiments of different soils: two Oxisols and
an Ultisol. Intact samples were subjected to wetting/drying cycles. Soil physical attributes
were determined before compaction, after compaction, and after one, two and three
wetting/drying cycles. The soil organic matter and clay content was greater in Oxisols, with
iron oxides presence. After compaction and three wetting/drying cycles, soil bulk density,
total, macro and microporosity and soil permeability to air returned to values close to the
original ones. Macroporosity was the most affected attribute by compaction and showed
the greatest recovery. Greater resilience was found in Oxisols, due to greater in organic
matter and clay content with the presence of iron oxides.
Keywords: Soil physical attributes; Soil resilience; Conservation agriculture.
36
ROOT VOLUME OF PERENNIAL GRASSES AND THEIR RELATION TO THE
AGGREGATION OF A CONSTRUCTED SOIL AFTER COAL MINING
Luiz Fernando Spinelli Pinto1,2, Lizete Stumpf2, Eloy Antonio Pauletto2, Fabrício da Silva
Barboza2, Leonir Aldrighi Dutra Junior2, Luciano Oliveira Geissler2, David de Lima de
Souza2, Renata Pinto Albert2
1
lfspin@uol.com.br; 2Universidade Federal de Pelotas (UFPel).
The causes of soil degradation during coal mining are related to the removal of the
vegetation and soil horizons and rocks for the extraction of the coal seams. The repeated
traffic of heavy-machinery during the restoration of the mined area is responsible for a high
degree of compaction in the constructed soils. The recovery of soil aggregation,
accumulation and persistence of organic matter over time are relatively well understood in
agricultural soils; however, are poorly understood in the case of constructed soils in mined
areas. The objective of the study is to analyze the effect of the root volume of perennial
grasses in the aggregation of a constructed soil after 103 months of introduction of plant
species. The study was conducted in a minesoil constructed in 2003, located in Candiota
RS (Brazil), and the evaluated plants were Hemarthria altissima, Paspalum notatum cv.
Pensacola, Cynodon dactylon cv. Tifton, and Urochloa brizantha. For sampling of roots 16
monoliths using pinboards were used (four replicates per treatment) with dimensions 0.40
m length x 0.30 m height x 0.035 m wide, which were washed, photographed, separated
by layers, cut, and scanned. The root volume was determined with the Software
SAPPHIRE. For soil aggregation study disturbed samples were collected for determination
of distribution of water stable aggregates and aggregate mean weight diameter (MWD).
Both in 0.00-0.10 m and in 0.10-0.20 m layers Urochloa brizantha showed the highest root
volume (0,032 m3 m-3 and 0.017 m3 m-3, respectively), followed closely by Hemarthria
altissima (0.023 m3 m-3 and 0.010 m3 m-3, respectively), with lower values for Paspalum
notatum (0.008 m3 m-3 and 0.002 m3 m-3, respectively) and Cynodon dactylon (0.011 m3 m3 e 0.008 m3 m-3, respectively). In 0.20-0.30 m layer the treatments did not differ from each
other and the values ranged from 0.002 to 0.004 m 3 m-3. It was observed that in the layer
with greater presence of roots (from 0.00 to 0.10 m), regardless of plant species, the
percentage of macroaggregates and the MWD were lower (from 84.06 to 92.25% and 2.51
to 3.39 mm, respectively), while in the layers where the presence of roots was less
concentrated (0.10-0.20 m) or almost nonexistent (0.20-0.30 m), the percentage of
macroaggregates and the MWD were higher (89.36 to 96.16% and from 3.10 to 4.66 mm,
respectively). This indicates that the recovery process of the mined soil structure is slow
and involves the breakdown of aggregates formed by compression in the compacted soil
layer, to subsequently form new aggregates by edaphic processes. Thus, the formation of
"edaphic" aggregates is actively taking place in the 0.00 to 0.10 m layer, but in the 0.100.20 m layer there is still the predominance of cohesive aggregates formed by
compression; nevertheless, the process of breakdown by the action of the roots is already
beginning to occur, through their development between soil cracks, as observed in the soil
monoliths.
Keywords: Root system; soil structure; compaction, pinboard method.
37
SAND SETTLING TIME FOR DETERMINATION OF TEXTURE CLASS OF
AN INCEPTISOL
Bruno Vizioli1, Mariana Alves Ibarr1, Sísara Rocha Oliveira1
1
Graduate program in Soil Science - Federal University of Paraná. Department of Soil Science and Agricultural Engineering - UFPR;
1540, Funcionarios Street Juvevê - Curitiba - PR. brunovizioli@gmail.com
The textural class is the most important soil physical characteristic, and from that, other
features, attributes and the best management way can be understood. The texture can be
determined based on clay, silt and sand proportion of a soil. This determination is based
on sand settling time, maintaining only the clay in suspension. The most widespread
methodology in Brazil adopts 2 hours for sand sedimentation. The purpose of this study
was to evaluate the sand settling time variation to determine the textural class of an
Inceptsoil in Curitiba-PR. In August 2014 were collected deformed soil samples at depths
of 0.0-0.1 and 0.1-0.2 meters in an Inceptsoil at the Federal University of Parana Botanical Garden campus, in a Pinus taeda cultivation area. The samples were submitted
to mechanical agitation with NaOH solution for 16 hours to complete particles dispersion.
After agitation, the contents were transferred to a 1000 mL graduated cylinder and were
adopted as treatments three settling times after reading the silt density (40 seconds after
transfer): 2 hours, 4 hours and 7 hours. The solution density determination was
made by using a Bouyoucos densimeter at each time and for each layer evaluated with
three replicates. After determination of clay, silt and sand values, a soil textural
classification was made, according to the Brazilian Society of Soil Science. Two hours of
sand and silt settling were insufficient to obtain the soil class. At this time, for all evaluated
repetitions, the total sand content had not stabilized, being the silt fraction measured as
sand fraction. However, when the settling times of 4 and 7 hours compared to the usual
time, the total sand and silt values have stabilized in all replicates, taking in to account the
settling time that may influence specially the large particles determination, because silt
particles probably take more than 2 hours to settle along with the sand. Carrying out the
solution density measurement, 2 hours after mechanical agitation, some particles of
silt were still in suspension, what could lead to errors in determining the textural class,
reflecting the inadequate soil management. Therefore, the soil classification with 2 hours
of settling was, very clayey, and after 4 and 7 hours of settling was, clayey. So, it was
concluded that time is effective to determine the texture class of an Inceptsoil.
Keywords: Texture; clay; soil classification.
38
SHEAR STRENGTH PARAMETERS OF MATERIALS FROM A LANDSLIDE SCAR
Graziela Maziero Pinheiro Bini1, Jéssica Gerente2, Edna Lindaura Luiz3
1
Universidade Federal de Santa Catarina - CFH/UFSC grazielabini@gmail.com. 2Universidade do Estado de Santa Catarina
FAED/UDESC jessicagerente@gmail.com. 3Universidade do Estado de Santa Catarina – FAED/UDESC elinluiz@uol.com.br
–
This paper aims to compare shear strength parameters from soil material of a landslide
scar, in order to verify which type of material is the most prone to rupture. The landslide
scar corresponds to the coordinates 696579.969S and 702763.451W (SIRGAS 2000/UTM
22S), and it is located in Gaspar/SC - Brazil. This landslide occurred during the intense
rainfalls of November/2008, when the extreme precipitation culminated in a natural
disaster. In the study area, the geologic formation corresponds to enderbites (metamorphic
rock). Due to the tropical clime and geology, the hillslopes have deep weathering mantles.
In the landslide scar, soil horizons A and B are thin, while horizon C is thick. In the last
horizon, there is a change in the grain texture and structure as the depth increases. At the
landslide scar horizon C it was collected samples to particle size analysis in the depth of
1.70 m (sample 01), 4.50 m (sample 02) and 7.40 m (sample 03). For all samples it was
estimated cohesion and internal friction angle through a Morh’s Circle. Both soil proprieties
were measured by using a Torsional Vane Shear Tester (TVST) and a Pocket
Penetrometer. The TVST indicates the shear stress and the Pocket Penetrometer
indicates the compressive strength. In the superficial sample (sample 01) it was found
35% of sand, 49% of silt and 16% of clay. In the sample 02, it was found 36% of sand,
63% of silt and 1% of clay. In the last sample (03) it was found 41% of sand, 41% of silt
and 18% of clay. Regarding the shear strength parameters, the sample 01 had an internal
friction angle of 58° and cohesion of 4.71 kg/cm². The sample 02 had 24° as internal
friction angle and 3.50 kg/cm² as cohesion. The last one, sample 03, had an internal
friction angle of 46° and cohesion of 6.47 kg/cm². The middle sample (sample 02) had the
highest amount of silt material. In all the samples, clay size was low mainly because they
were taken from horizon C, where the weathering is still incipient. The lowest value of
cohesion and internal friction angle corresponded to sample 02, which is the one that had
the highest amount of silt and the lowest amount of clay. The high percentage of silt does
not give a high internal friction angle because there is not enough roughness among the
grains. The small percentage of clay in sample 02 does not allow cohesion among the soil
particles. In the samples 01 and 03, the resistance probably comes from the highest sand
and clay percentages, which gives highest internal friction angle and cohesion,
respectively. Therefore, it is concluded that the material most prone to rupture is located at
4.5 meters depth in the horizon C, in which the low shear strength is probably influenced
by its silty texture.
Keywords: Shear strength; mass movement susceptibility; soil properties.
39
SIMULATION OF SOIL HYDRAULIC FUNCTIONS BY PEDOTRANSFER FUNCTIONS SPLINTEX AND ROSETTA
Silva, A.C.1, Armindo, R.A.2, Brito, A.S.3, Silva, E.T.2
Master's student of the Soil Science Post Graduation Program – Federal University of Paraná (UFPR). email:
engalecalegari@gmail.com; 2 Professor of the Department of Soils and Agricultural Engineering - UFPR; 3 Professor of the Department
of Soils - Federal Institute of Education, Science and Technology – IFET Baiano.
1
The knowledge of the soil water retention curve (SWRC) is essential to understand and
model the hydraulic soil processes. However, the determination of the soil hydraulic
properties are considered expensive and difficult to be realized, especially in large-scale
monitoring. One alternative that has been used in soils from tropical climate are the
Pedotransfer Functions (PTF's). PTF´s are equations with statistical, empirical or
physically based foundation, used to estimate soil characteristics of difficult determination
from other more easily obtained. This work aimed to evaluate the program PTF-SPLINTEX
in determining the parameters of equation the van-Genuchten for sandy and clay soil
characteristics and to compare the performance of PTF-SPLINTEX against PTFROSETTA in simulation of the hydraulic functions, including SWRC parameters. In these
simulations, databases were used consisting of 103 sampling points, with 60 sampling
points of a sandy soil located in an experimental area in Piracicaba, São Paulo, Brazil, and
43 sampling points of soils with clay characteristics obtained in databases from various
regions of Brazil. Each sample point consisted of soil texture information (sand, silt and
clay), density (bulk and particles), soil porosity (saturated soil moisture), in addition to
water content information in respective matric potentials. The performance of PTF's
estimator as the soil moisture was evaluated with linear regression analysis between the
observed and estimated using the Pearson correlation (r). To check the accuracy of the
models, we used the mean absolute error (MAE) and root mean square error
(RMSE).Regarding the performance of the PTF-SPLINTEX compared to PTF-ROSETTA,
it proved to be an efficient model with lower systematic errors, presented RMSE average
of 0.0298 m3 m-3 and correlation of 0.98% for sandy soil, and average RMSE of 0.0440 m 3
m-3 and correlation of 0.92% for the clay soil, compared to the observed data. The PTFSPLINTEX performance to predict SWRC parameters and other soil hydraulic functions
was efficient resulting in an accuracy and precise alternative.
Keywords: Soil water content; soil water retention curve; soil hydraulic conductivity.
40
SOIL ATTRIBUTES OF AMAZON UNDER DIFFERENT USES: AN APPROACH BASED
ON DECISION TREE
Raquel Stucchi Boschi1*, Laura Fernanda Simões da Silva2, Maria Leonor Lopes-Assad3,
Luiz Henrique Antunes Rodrigues4, Miguel Cooper2
1
Embrapa Agriculture Informatics, 2University of São Paulo/Luiz de Queiroz College of Agriculture, 3Center of Agricultural Sciences,
Federal Univ. of São Carlos, 4School of Agricultural Engineering, Univ. of Campinas. *Corresponding author (raboschi@gmail.com).
The future of the Amazon biome depends on the capacity of ecosystems to withstand the
disturbance caused by land use and climate change. Understanding soil behavior under
different land uses found in Amazon is essential for the adoption of alternative systems
aiming soil conservation. The objective of this study was to apply decision tree models
(DT) to identify soil attributes affected by the change of forest use for pasture, from data
obtained by structural analysis in two toposequences in eastern Amazonia. The study area
is located in Nova Ipixuna, in the Southeast of Para state, where it can be found a
concentration of rural settlements of agro-extractive character. Three DTs were built using
a different set of soil attribute as potential predictors and the type of use, forest (F) or
pasture (P), as the target attribute. For the first DT, the inputs were: horizon position, sand,
silt, clay, organic C (C), bulk density (Bd), CEC, pH, macro, meso, and microporosity. For
the second DT, we selected attributes that may easily change with soil management
practices: structure type, C, Bd, CEC, pH, macro, meso, micro and total porosity. For the
last DT, we used attributes that are easily to measure: sand, silt, clay, C, Bd, CEC, pH.
The DTs were evaluated based on the overall accuracy. The DT allowed understanding
the main attributes responsible for the differentiation of soil under pasture and forest. The
best DT was the first with an accuracy of 65%. The second and third presented an
accuracy of 57%. The pH, structure type, and Bd were the main attributes selected by the
DTs for the differentiation of the systems. These attributes can be considered the most
affected by the change of land use. The knowledge acquired can be useful to define
sustainable use systems in areas of family farming.
Keywords: Soil degradation; agro-extractive systems; project of rural settlement.
41
SOIL BULK DENSITY AND SHAPE OF SWEET POTATO ROOT UNDER DIFFERENT
SOIL MANAGEMENTS
Amarílis Beraldo Rós
Email: amarilis@apta.sp.gov.br. Agência Paulista de tecnologia dos Agronegócios - Polo Alta Sorocabana.
Studies about reduced tillage in soil cultivated with roots and tubers are rare and
controversial. Thus, this study aimed to assess the impact of tillage systems on soil bulk
density of an Alfissol and on the shape of sweet potato tuberous roots. The experiment
was conducted in randomized blocks design, in split-plot scheme. The plots consisted of
five treatments: tillage with moldboard plow and disking (MD), tillage with moldboard plow,
disking and making mounds (MDM), making mounds without previous soil mobilization
(M), reduced tillage (RT) and reduced tillage with straw on the soil surface (RTS). The
subplots consisted of collect periods: 90, 120, 150 and 180 days after planting (DAP) of
the sweet potato crop. Soil bulk density was determined by volumetric ring method. Shape
of sweet potato tuberous root was assessed by the length / diameter of roots. There was
no significant interaction between soil bulk density and collect periods; and between shape
of sweet potato tuberous roots and collect periods. The largest values of soil bulk density
were observed in the managements without soil mobilization (RT and RTS), while the
lowest value occurred in M and MDM. MD presented intermediate value. The values of soil
bulk density found in MDM and M were also influenced by the increase in the volume of
tuberous roots, because the soil of mounds can move laterally. All soil managements with
soil mobilization resulted in lower soil bulk density than reduced tillage (RT and RTS) and
it was expected because the soil mobilization decreases soil bulk density in managed soil
layer. The soil bulk density was not influenced by the presence or absence of straw in the
same soil managements (RT and RTS). The soil management and the collect period
affected shape of roots. The tuberous roots showed values of length / diameter in
decreasing order in MDM, M, MD and reduced tillage (RT and RTS). There was reduction
of the length / diameter of the root from 90 DAP to 150 DAP. After this period the roots
started to increase the value. Thus, the making mound activity causes more
disaggregation of the soil than plowing and harrowing activities, and it results in lower
value of soil bulk density. And sweet potato tuberous roots are sensitive to soil bulk density
and respond to changes in its format.
Keywords: Ipomoea batatas; no-tillage; conventional tillage; mound.
42
SOIL COMPACTION ASSESSMENT FOR DIFFERENT AMOUNTS OF SURFACE
STRAW UNDER NO BURN SUGARCANE CULTIVATION IN A CLAYEY SOIL
Henrique Pose Guerra1,2, Izaias Pinheiro Lisboa1,3, Caio Fernandes Zani1,4, Carlos
Clemente Cerri1,5
1
Centro de Energia Nuclear na Agricultura, Laboratório de Biogeoquímica Ambiental, Av. Centenário, 303, 13400-970, Piracicaba (SP),
Brasil. 2 henrique.guerra@usp.br, 3iplisboaa@gmail.com, 4czani@cena.usp.br, 5cerri@cena.usp.br
Soil compaction in agricultural areas managed under no burn harvesting sugarcane
system has been a limiting factor in many of productive areas, particularly in areas with
clayey soils. The main goal of this study is characterize the soil compaction and its relation
to the amounts of straw and the density of the soil from the surface until 0.50 m depth. An
experiment was carried out in order to represent the dry season. Row spacing was
combined (0.90 and 1.50 m).The experiment consisted of four blocks and six doses of
straw (0%, 20%, 47%, 79%, 100%, 100% windrowed) using different revolutions per
minute (RPM) in the primary and secondary extractors of the harvester providing four
doses achieved. The zero percent doses were established manually removing all the straw
from the respective plots and the major doses were obtained by 100% of the straw
windrowed in the larger spaced rows. Soil bulk density was measured in each block and
three sides of the trench next to the experimental area. Soil penetration resistance was
measured with a DLG PNT-2000 penetrometer in the middle of the 0.90 m spaced rows
with three measurements in each plot. Five depths were evaluated: 0-10 cm, 10-20 cm,
20-30 cm, 30-40 cm and 40-50 cm. Densities (standard deviations between brackets) for
the five layers were, respectively 1.32 g cm-3 (0.11), 1.37 g cm-3 (0.11), 1,38 g.cm-3 (0.12),
1,42 g.cm-3 (0,03) and 1.40 g.cm-3 (0.01). The penetration resistance (PR) was distributed
in averages for each straw dose and layer. For the 0% dose (0-10: 0.25 MPa; 10-20: 0.68
MPa; 20-30: 1.03 MPa; 30-40: 1.21 MPa; 40-50: 1.43 MPa). At 20% dose (0-10: 0.11
MPa; 10-20: 0.32 MPa; 20-30: 0.93 MPa; 30-40: 1.12 MPa; 40-50: 1.42 MPa). At 47%
dose (0-10: 0.19 MPa; 10-20: 0.69 MPa; 20-30: 0.99 MPa; 30-40: 1.12 MPa; 40-50: 1.40
MPa). At 79% dose (0-10: 0.28 MPa; 10-20: 0.63 MPa; 20-30: 1.10 MPa; 30-40: 1.43
MPa; 40-50: 1.61 MPa). For the 100% dose (0-10: 0.21 MPa; 10-20: 0.68 MPa; 20-30:
0.99 MPa; 30-40: 1.04 MPa; 40-50: 1.31 MPa). The 100%W dose (0-10: 0.26 MPa; 10-20:
0.65 MPa; 20-30: 0.90 MPa; 30-40: 1.11 MPa; 40-50: 1.31 MPa). No significant difference
in the treatments was observed at a 5% level of probability. The correlation between the
penetration resistance and bulk density showed an R² = 0,8373. In summary, the use of no
burned system regardless the amount of straw on the ground did not provide significant
changes in penetration resistance values. These are preliminary results. Subsequent
measures may show changes in penetration and compaction levels.
Key-words: Sugarcane; straw; penetration resistance; bulk density.
43
SOIL EROSION RELATED PROCESSES IN A SMALL SUGARCANE WATERSHED OF
SOUTHEAST BRAZIL
Taciana Figueiredo Gomes; Robson Willians da Costa Silva, Jorge Marcos de Moraes,
Edmar Mazzi; Luiz Antonio Martinelli
Centro de Energia Nuclear na Agricultura (CENA/USP) – Laboratório de Ecologia Isotópica. Email of the corresponding author:
tgomes@cena.usp.br
Brazil is the world largest sugarcane producer, with a cropped area of approximately 10
million hectares. One of the neglected environmental problems of sugarcane fields is soil
erosion. In this study, two pluviometers were installed in an open area near to crop field in
order to measure the amount and intensity of liquid precipitation over a period of time.
Surface runoff generation and soil detachment were estimated by plots installed in
managed and riparian areas. Bathymetry was carried out in the stream channel to
estimate the soil mass settled on the stream bed. The source of this material, was
investigated by carbon (δ13C) and nitrogen (δ15N) stable isotopic compositions. In
sugarcane field, in the earlier stage of the crop, the rain intensity strongly influenced runoff
generation and soil detachment. However, these effects were minimized with the plant
growth, that increased drain interception. In riparian areas, runoff and soil detachment
occurred only during intense events, that represented 37% of all sampled events. The
averages δ13C and δ15N of soil from forest areas were -27.0 ± 0.3 ‰ and 3.7 ± 0.1 ‰,
respectively. In the sugarcane areas the averages δ13C and the δ15N increased to -20.3 ±
0.2 ‰ and 6.5 ± 0.3 ‰, respectively. In the stream bed, the average δ13C value was equal
to -23.1 ± 0.4 ‰ and the average δ15N equal to 5.9 ± 0.2 ‰, indicating that at least 60% of
this material was generated in the sugarcane areas.
Keywords: Sugarcane; stables isotopes; soil detachment; surface runoff; sedimentation.
44
SOIL HYDRAULIC PROPERTIES AND ITS IMPLICATIONS FOR OVERLAND FLOW
GENERATION IN SUGARCANE PLANTATION AND RIPARIAN FOREST
Robson Willians da Costa Silva, Luiz Felippe Salemi, Rafel Pires Fernandes, Taciana
Figueiredo Gomes, Jorge Marcos de Moraes, Luiz Antonio Martinelli
Institution: Centro de Energia Nuclear na Agricultura (CENA/USP) – Laboratório de Ecologia IsotópicaEmail of the corresponding
author: robsonwillians@yahoo.com.br
Brazil is the world’s largest producer of sugarcane with 95% this crop under conventional
tillage and rainfed conditions. The continuous use of the soil modifies its intrinsic
characteristics, which changes according to the use and management applied. Soil tillage
practices can affect soil hydraulic properties and processes dynamically in space and time
with consequences on soil water storage, runoff generation, chemical movement, plant
growth and erosion processes. Such changes are influenced by heavy machinery traffic
(e.g. wheel-track truck and trator) that may have significant effects on soil compaction and
related hydraulic properties, such as bulk density, macro and microporosity and saturated
hydraulic conductivity, producing hydrological impeding layer. The objective of this study
was to quantify field-saturated hydraulic conductivity (Ksat) in a ratoon 5th cycle and a
riparian forest to evaluate its effects on overland flow generation. We measured at 25
points randomly distributed in a watershed with an area of 7 ha, with 15 points in
sugarcane plantation and 10 in riparian forest, in the depths of 0.15 m, 0.30 m, 0.50 m
0.90 m. The datasets indicated non-Gaussian behavior of the Ksat distributions. Thus, for
comparisons among land uses, we analyzed the raw data by application of the nonparametric Kruskal–Wallis rank sum test. The Ksat results exhibited decreasing median in
depth in sugarcane (0.15 m - 8.62 mm h-1; 0.30 m - 5.84 mm h-1; 0.50 m - 4.78 mm h-1;
0.90 m - 0.96 mm h-1) and in riparian forest (0.15 m - 51.70 mm h-1; 0.30 m - 24.78 mm h-1;
0.50 m - 7.97 mm h-1; 0.90 m - 3.54 mm h-1). The Ksat median showed significant
differences between land uses only at 0.15 and 0.30 m (p= 0.043 and p= 0.015,
respectively). The low values at the first layers of the soil in sugarcane is possibly
generated by raindrop impact on bare soil during re-growth and soil compaction for
machinery. Assuming the median of Ksat to 0.15 m depth as an indicator of soil infiltration
in a rainfall event, we found less than 1% of the events exceeded Ksat this layer in the
riparian forest during two years of monitoring the intensity of the rainfall, while in
sugarcane it was about 20-25%. These results showed a more frequent hortonian
overland flow generation on the sugarcane compared to the riparian forest. Furthermore,
presumably saturation overland flow might be generated due to sharp decrease of Ksat at
shallow depth regardless the land cover type.
Keywords: Saturated hydraulic conductivity; overland flow; sugarcane; riparian forest.
45
SOIL MANAGEMENT SYSTEM EFFECTS ON SOIL WATER MOVEMENT UNDER
NON-SATURATED CONDITIONS
Rafael Villarreal1*, Luis A. Lozano1, C. Germán Soracco1, Guillermo O. Sarli1
1
Applied physics area. Faculty of Agronomic and Forestry Sciences, National University of La Plata, 60 av. and 119 st, La Plata (1900),
Buenos Aires, Argentina.* rafaevillarreal@gmail.com
Soil hydraulic properties determination is crucial in order to assess water entry,
accumulation and transport into the soil profile. Diffusivity (D) and sorptivity (S) are
important in order to characterize the ability of the soil to transport water under nonsaturated conditions. These conditions are the most frequent in agricultural soils. However,
there are few studies comparing the effects of different management systems on these
properties, because the determination is difficult and time consuming. The study of
horizontal infiltration, where the gradient of gravitational component of soil water can be
neglected, allows the determination of non-saturated soil water properties. The aim of this
study was to determine the effect of different soil management systems on D and S
estimated from laboratory horizontal infiltration experiments. Additionally, two
methodologies to obtain D from horizontal infiltration were compared. The experiment was
carried out near the city of La Plata, in the Research Field “Don Joaquin” belonging to the
Faculty of Agricultural and Forestry Sciences, National University of La Plata (37º11’ S,
57º50’ W). The soil was classified as typic paleudol and the texture of the upper layer was
silty clay loam. The soil A-horizon under three management systems (T1: Natural
grassland, T2: direct drilling mayze, and T3: Polyphitic Pasture) was sampled. The
samples were sieved through 2 mm sieve, and then the soil was packed into horizontal
columns with 10 cm diameter and 70 cm large. Water content and time was measured
using 5 moisture sensors placed at 10, 20, 30, 40 and 55 cm from water source.
Cumulative horizontal infiltration was measured directly from a graduated reservoir. D was
estimated following the method of Whisler et al. (1968). Two methodologies derived from
the traditional method of Phillip (1957) were used and compared to determine S. The first
one (M1) estimates S from the cumulative infiltration, and the second one (M2) estimates
S using initial and final water contents at all measured points, throw Boltzmann
transformation. The values of S obtained by the two methodologies were not significantly
different. The dependence of D with water content was exponential (R 2=0.7053; 0.8049
and 0.8699 for treatments 1, 2 and 3, respectively). The soil management system affected
significantly both S and D values. They were significantly greater for T2 as compared to T1
and T3. Overall, mean values of S estimated with M1 were 0.0972, 0.1571, and 0.1027
cm.s-0,5, for T1, T2 and T3, respectively. The mean values of S estimated by M2 were
0.0991, 0.1615, and 0.1023 cm.s-0,5, for T1, T2 and T3, respectively. Finally, mean values
of D at 20 % of water content were 0.00209, 0.00208, and 0.0037 cm 2.s-1, for T1, T2 and
T3, respectively. These results show that this soil under T2 has the ability to transmit water
faster under non saturated conditions.
Keywords: Sorptivity; diffusivity; infiltration.
46
SOIL PERMEABILITY COEFFICIENT TO VINASSE APPLICATION
Morais, L.R.B.1, Armindo, R.A.2
1
Student of Environmental Engineering - UFPR. lianarocio@gmail.com. 2Professor from the Department of Soils and Agricultural
Engineering - UFPR.
Knowledge of the liquid in the soil permeability is a property of paramount importance for
the development of agricultural crops and in environmental studies. When the liquid is
water, the hydraulic permeability property is evaluated and known, however it is not normal
to use other liquids in this determination. Since the late 70’s, a residue of alcohol
industries, known as vinasse, with favorable chemical composition has been used as biofertilizer, because it has high levels of potassium, nitrogen, organic matter, and other
contents. Its use became more usual after the ban on disposal of vinasse in streams and
rivers, because of their high polution power. Due to lack of studies related to the vinasse
rate through in the soil and the lack of federal and state legislation, this work aims to
evaluate the soil permeability coefficient to vinasse movement under four different soil
managements. So, soil physical properties and the permeability coefficient to water and
vinasse application of samples collected in sugarcane area from Morretes city, Paraná
State, Brazil will be evaluated. To determine the physical properties of the soil methods
were used constant head permeameter method, under four different soil managements:
sugarcane crop area (SCC), fallow (FLW), native forest (NF) and fallow with vinasse
application (FLV); hydrometer method; volumetric rings and pycnometer method. The total
porosity can be determined from the difference between the unit value and the relation
between bulk density and particles density. The microporosity will be obtained in
undisturbed samples associating them with water content of 60hPa of pressure, so
macroporosity will be also calculated as the difference between porosity and
microporosity. Results obtained showed that the SCC, FLW, NF and FLV areas in depth of
0-0,20m have sandy clay loam soil. In depth of 0,20-0,40m, sugarcane crop area has clay
soil and the other areas have sandy clay loam soil. The particle density (ρp) is between
2502.5 to 2932.62 kg/m³ in the study area. The hydraulic permeability coefficients of water
flow (Kw) and vinasse (Kv) in depth 0-0,20m are 9.05, 17.86, 305.90, 31.66, 0.59, 2, 54,
28.55 and 5.01 mm/h, respectively for the areas. In the depth of 0,20-0,40m were 6.84,
34.81, 172.51, 218.17, 3.43, 3.79, 71.47 and 63.11 mm/h, respectively for areas. There is
low linear correlation between values of Kv and Kw for the entire study area (R² <0.6098).
The values obtained show that K vinasse is smaller than the K of water and the viscosity is
responsible for this difference. And the equation for obtaining the specific vinasse K using
K of water is not valid, because these values have no linear correlation.
Keywords: Hydraulic conductivity; fertirrigation; Darcy’s law.
47
SOIL PHYSICAL ATTRIBUTES: SUSTAINABILITY ASSESSMENT IN CROPLIVESTOCK-FOREST SYSTEMS
Alcione Herminia da Silva1, Verediana Fernanda Cherobim1, Daniela Jerszurki1, Nerilde
Favaretto2, Karina Maria Vieira Cavalieri2, Jeferson Dieckow2, Lucilia Maria Parron3
Student – Soil Science Graduate Program - UFPR. E-mail: herminiadasilva@yahoo.com.br, verediana.cherobim@gmail.com,
dani_jerszurki@hotmail.com. 2Professor – Soil Science and Agricultural Engineering Department- UFPR: E-mail: nfavaretto@ufpr.br,
karina.cavalieri@ufpr.br, jefersondieckow@ufpr.br. 3Researcher - Embrapa Forest E-mail: lucilia.parron@embrapa.br.
1
Seven agricultural and forest long-term (7-25 years) systems located in Ponta Grossa,
Paraná, Brazil, were investigated: integrated crop-livestock (iCL) (3 to 10% slope),
integrated crop-livestock-forest (iCLF) with Eucalyptus dunnii (5 to 13%), native pasture
(grazed) (NPg) (7 to 11%), Eucalyptus dunnii forest (EF) (6 to 11%), no-till (NT) (3 to 9%),
native pasture (no grazed) (NPng) (6 to 14%), and native forest (NF) (5 to 11%). The
experiment was carried out in an incomplete block design with seven treatments and three
replicates, totaling 21 experimental units. Four soil cores were taken from each field trench
(two each experimental unit) at four depths (0-5, 5-10, 10-20 and 20-30 cm). The following
soil physical attributes were determined: water infiltration, total, macro and microporosity,
bulk density and saturated hydraulic conductivity. The crop systems (iCL, iCLF and NT)
had lower final infiltration rate than the forest and native pasture systems (NPg, EF, NPng
and NF). As expected, the highest final infiltration rate was found in the NPng and NF
systems. The saturated hydraulic conductivity and the macroporosity were higher in the
iCLF system compared to iCL system despite having similar final infiltration rate. Bulk
density in the iCLF system was higher than iCL mainly at the upper depths (0-10 cm). In
deeper layers, the bulk density decreased in the NPg system with lowest value (1.38 Mg
m3) at 20-30 cm, indicating the grass roots effect. In general, the systems with highest
ecological complexity presented the best results in terms of physical attributes.
Keywords: Conservation systems; integrated systems; soil management; soil physical
quality; agroecosystems.
48
SOIL PHYSICAL ATTRIBUTES IN SHORT-TERM INTEGRATED AGRICULTURAL
SYSTEMS
Coblinski, J.A.1, Goularte, G.D.1, Favaretto, N.2, Dieckow, J.2, Moraes, A.3
1
Students - Soil Science Graduate Program - UFPR. E-mails: coblinskijoao@gmail.com; gabrield.agro@gmail.com. 2Professors- Soil
Science and Agricultural Engineering Department - E-mails: nfavaretto@ufpr.br; jefersondieckow@ufpr.br; 3Professor - Plant Production
Department - UFPR. E-mail: anibalm@ufpr.br.
Land use and management influence soil physical attributes, causing agronomical and
environmental problems. The objective was to evaluate the soil physical attributes at
different depths in different soil use and management systems - short-term (first year). The
study was conducted in the Canguiri Experimental Farm, Federal University of Paraná,
Pinhais, Brazil. Randomized block was the experimental design with three replicates and
three treatments: single crop production (C); pasture (P) and integrated crop-pasture (ICP)
in a Cambisol under no-tillage system. Soil samples were taken at four depths (0-5; 5-10;
10-20 and 20-30 cm) and analyzed for texture, bulk density, hydraulic conductivity, total
porosity, macro and microporosity. Texture was determined by hydrometer and bulk
density by volumetric ring method. Hydraulic conductivity of saturated soil was determined
by the constant head permeameter. Total porosity was obtained by saturation,
macroporosity by 60 cm water column and microporosity by the difference of the
macroporosity and total porosity. Descriptive and exploratory analysis of the average and
coefficient of variation were applied. Non parametric Kruskal Wallis was used for mean
comparison. Main component analysis was used to identify the variables dependence. The
physical attributes at each depth were not different (p<0.05) among the systems. The
principal component analysis showed a dependency between macroporosity and hydraulic
conductivity of saturated soil.
Keywords: Integration systems; hydraulic conductivity; porosity; bulk density.
49
SOIL SURFACE TEMPERATURE UNDER OAT RESIDUE ESTIMATED FROM
METEOROLOGICAL DATA
Anderson Luiz Zwirtes¹*, Dalvan José Reinert¹, Paulo Ivonir Gubiani¹ Eduardo Augusto
Müller¹
*
andersonzwirtes@yahoo.com.br. 1 Federal University of Santa Maria - RS.
The temperature (T) and water content (θ) in the soil vary over time and space. The
simulation of T and θ with physics-based differential equations which describe the
transport of heat and water in the soil can be obtained using Hydrus-1D.To simulate T
within soil profile, the Hydrus-1D requires as boundary condition the temperature of the
soil surface (Ts), which can be field measured or estimated. As the T s and air temperature
(Tair) are determined largely by the same meteorological variables is believed to be
possible to estimate with good accuracy the Ts depending on the Tair and other
meteorological variables provided by automatic weather stations. The objective of this
work is to generate equations for estimating T s covered with different amounts of oat
straw, using hourly meteorological data available in automatic weather stations. The
experiment is being conducted in a Paleudalf, located in Santa Maria - RS, 29°43’13”S and
53°42’23”W coordinates. On the soil surface was placed 0, 3, 6, 9 Mg ha -1 of dry oat straw
(Avena strigosa), harvested at flowering. The meteorological data for the period from
November 25, 2014 to February 20, 2015 were obtained from the meteorological station
located at 1600 m far from the experiment. The T s was measured with thermocouple type
T (copper-constantan) positioned right within first millimeters of soil depth. For each
amount of straw, the Ts data was grouped to meteorological data of T air, solar radiation
(R), wind speed (V) and precipitation (P) in order to obtain multiple linear equations
Ts = aTair + bR + cV + dP + f where, a, b, c, d and f are adjustment coefficients. The
coefficient of determination (r²) for all obtained equation were above 0.7. Linear equations,
Ts = aTair + b, and quadratic, Ts = aTair2 + bTair + c, had r² lower than 0.75. These results
indicate that the use of meteorological variables R, V and P in addition to the T air improves
the estimate of Ts. The Ts for each amount of black oat straw on the soil surface, presents
behavior associated with the heat input and output in the soil, affected by the straw on the
soil surface, and can be estimated when there is continuous and hourly meteorological
data.
Keywords: Prediction; Hydrus-1D; water and heat flux.
50
SPATIAL VARIABILITY OF LATOSOLS (OXISOLS) STRUCTURE SUBJECTED TO
THE COFFEE CULTIVATION OF DIFFERENT AGES
Carducci, C.E.1, Oliveira, G.C.2, Rossoni, D.F.3
Corresponding author: ec.carducci@ufsc.br, Federal University of Santa Catarina –campus Curitibanos. 2Federal University of Lavras.
State University of Maringá
1
3
The agricultural practices modify the soil structure, where they are the conservationist
character, promote the ground structural benefits such as better distribution of air and
water in the soil. The study aimed to assess the structural variability of Latosols (Oxisols)
under coffee crop with different deployment times. We collected soil samples undisturbed
in plexiglass in clayey oxidic Latosols, under two coffee crops: the first was young coffee
crop (three year) and the second was old coffee crop (six year) both conducted in the
same conservation management system. The soil was sampled between plants just below
the gypsum layer at 0.20-0.34m depth. To obtain the images soil cores were scanned in Xray CT scanner in 60 µm of spatial resolution. We used the “Semivariance 3D” plugin of
NIH ImageJ, in X-rays attenuation value of the grayscale image, we used geostatistical
analysis to build the semivariograms and to compare the semivariograms, we used the
prediction intervals (IP).The semivarigrams and the IP generated from CT images
identified structural changes in the soil promoted by conservation management system
and its effects over the deployment time. The management system promoted a greater
variability of the soil aggregates occurred in the young coffee crop (LN) especially in the
horizontal direction (X and Y) observed by the lower range and larger still values. Over
time these were reorganized soil aggregates in the horizontal direction, but with greater
spatial continuity of soil aggregates in all directions, specially in the vertical direction (Z).
Keywords: Semivariogram; soil structure; X-ray CT scan; prediction interval.
51
SPATIAL VARIABILITY OF PHYSICAL ATTRIBUTES AND OF THE SOIL
PERMEABILITY TO WATER AND FUELS
Gonçalves, L.1, Armindo, R. A.2, Turek, M. E.3; Botelho, L.L. 4, Souza, J. L. M.5
1
Master's Student of the Post - Graduate Program in UFPR Soil Sciences. E-mail: leticiag.ufpr@gmail.com; 2Professor of UFPR;
Graduate Student Course UFPR Environmental Engineering; 4Graduate Course Student at UFPR Agronomy; 5Professor of UFPR.
3
The increasing demand for fuels raises de risk of environmental accidents, mostly tipping
trains and trucks and spills from storage containers. This kind of accident causes damages
in soil, flora, fauna and human health, due to the high toxicity of some fuel components,
specially the BTEX (Benzene, Toluene, Ethylbenzene and Xylene). In Brazil, gasoline is
marketed with 25% of ethanol, which favors the co-solvency effect and increase the
environmental impact. The fate and behavior of spilled fuel on soils mainly depend on soil
physical properties (density, porosity, permeability, pore continuity) and fuel physical
properties (density and viscosity). This study aimed to evaluate the spatial variability of soil
physical attributes, especially the soil permeability to water and fuels. The experiment
used thirty-two deformed soil samples and thirty-two undisturbed soil samples, both with
three replicates, in an area of 0.5ha at a depth of 0-0.20m, at a spacing of 15X15m. In the
lab, were determined texture by densimeter method, bulk density (ρs) by volumetric ring
technique, particle density by volumetric flask, porosity by difference between the unit and
ρs/ρp and the saturated hydraulic water? permeability (Kw), gasoline permeability (Kg) and
diesel permeability (Kd) by variable-head permeameter. Results were analyzed by
classical statistics and geostatistic. The soil was classified as clay and its other attributes
were as expected, without compaction evidences. The K g was average 4 times bigger than
Kw, while Kd was average 1.2 times bigger than Kw. These found results can be due to
some physical-chemical characteristics of fuels that react with loads clay, occurring soil
dehydration and formation of fissures inducing preferential flow. For K d analysis, the
difference to Kw was smaller because of its large viscosity. These chemical characteristic
of fluids makes the water, gasoline and diesel intrinsic permeability (Ke w, Keg, Ked)
different from each other. Thus, there is an accident , the fuel plume will reach more easily
the water table . There was a coefficient of variation between average for soil physical
properties and high for the hydraulic permeability and intrinsic permeability, allowing the
use of geostatistics.The semivariogram adjustments were realized by GeoR package, in
software R, with best results to wave and spheric models for the most cases, based on the
Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The practical
range for the variables sand, silt, clay, ρs, ρp, porosity, Kw, Kg, Kd, Kew, Keg, Ked were
42.78; 29.74; 46.44; 45.52; 15.21; 22.91; 33.67; 24.34; 28.14; 26.90; 33.23 and 23.49 m,
respectively.
Keywords: Soil hydraulic permeability; soil hydraulic conductivity; geostatistic.
52
SPATIAL VARIABILITY OF PHYSICAL ATTRIBUTES IN AN ULTISOL IN LAND USE
OF SUGARCANE, PASTURE AND NATIVE FOREST
Teresa Cristina T. Pissarra1, Fabiana C. Reis2, Sergio Campos3
teresap1204@gmail.com – Profa. Adjunto, Faculdade de Ciências Agrárias e Veterinárias, UNESP – Univ Estadual Paulista, Câmpus
Jaboticabal, Departamento de Engenharia Rural. 2Mestre UNESP/FCAV. Bolsista CNPq. 3Prof. Titular, Faculdade de Ciências
Agronomicas, UNESP – Univ Estadual Paulista, Câmpus Botucatu, Departamento de Engenharia Rural
1
The knowledge of the soil physical properties in different land uses in a watershed is
indispensable for evaluating areas to manage sustainable farming practices and for areas
that must be preserved. The study was conducted in Córrego da Fazenda Glória
watershed, Taquaritinga Municipality (SP), in order to evaluate the spatial variability of
physical attributes. The main soil unit is Ultisol, and the land use/cover is of sugarcane,
pasture and native forest. Soil was sampled in a regular grid of 10 m, with a total area of 1
ha, at a depth of 0,0-0,1 m, in each land use/cover. The coefficient of variation of soil
density was low in all three areas and other attributes were presented as average. The
highest average total porosity was shown in the area of native forest, due to improved soil
structure in such coverage. All attributes had an average degree of spatial dependence,
except for macroporosity in pasture use, and microporosity and total porosity in the area of
natural forest, which showed a pure nugget effect, indicating randomness of the data. The
largest ones were affected by soil properties in the area of sugarcane, followed by pasture
and native vegetation.
Keywords: Geoestatistics; land use/cover; soil porosity; bulk density.
53
SPIA: A SOFTWARE FOR MICROMORPHOMETRIC CHARACTERIZATION OF PORES
FROM 2D IMAGE ANALYSIS
Miguel Cooper1*, Raquel Stucchi Boschi2, Vitor Boschi da Silva3, Laura Fernanda Simões
da Silva4
1,4
University of São Paulo/ESALQ,
(mcooper@usp.br ).
2
Embrapa Agriculture Informatics, 3University of São Paulo/ ICMC. *Corresponding author
Studies of soil porosity through image analysis are important to understand soil
functioning. However, the lack of a simplified methodology for the quantification of the
shape, number, and size of soil pores has limited the use of information extracted from
images. The present work proposes a software for the quantification and characterization
of the soil porosity from data derived from 2-D images. The user-friendly software was
developed in C++ that allows the classification of the pores according to size, shape, and
combinations of size and shape. Using raw data generated by image analysis systems the
software calculates the following parameters for the characterization of soil porosity: total
porosity (Pt), number of pores, pore shape, pore shape and pore area and pore shape and
equivalent pore diameter (EqDiam). In this study, the input file with the raw soil porosity
data was generated using Noesis Visilog 5.4 image analysis system, however other image
analysis programs can be used. In that case, the input file requires a standard format
necessary for processing by the software here presented. The software also shows the
descriptive statistics (mean, standard deviation, variance, and the coefficient of variation)
of the parameters considering the total number of evaluated images. The results show that
the software is a complementary tool for the analysis of soil porosity, allowing for a precise
and quick analysis.
Keywords: Soil structure; soil thin sections; soil porosity; micromorphometry; elongated
pores.
54
SURFACE AND INCORPORATED LIME EFFECTS ON SOME PHYSICAL ATTRIBUTES
OF A DYSTRUDEPT
André Carlos Auler1*, Luiz Fernando Pires2, Neyde Fabíola Balarezo Giarola2, Eduardo
Fávero Caires2, José Alfredo Baptista dos Santos3
1
Ph.D. Agronomy Student by State University of Ponta Grossa (UEPG); 2Titular professor of the UEPG; *Corresponding author:
aulerac@gmail.com
Liming is the most used practice to correct soil acidity. However, the dynamics of acidity
correction depends of the corrective application mode. The effectiveness of surface
application of limestone in the soil is limited. The incorporation of limestone increases its
effect and causes soil structure changes due to mechanical disturbance. In this context,
with the aim to evaluate the changes in physical attributes of a Dystrudept caused by
surface and incorporated liming, an experiment was performed in the Southeast of Paraná
state (Brazil). The treatments consisted of three limestone application modes (surface,
incorporated with plowing and harrowing, and incorporated with subsoiling and harrowing),
with and without the use of limestone (15 Mg ha -1). The limestone used contained 280,
200, 747 and 751 g kg-1 of CaO, MgO, reactivity and relative power of total neutralization.
Undisturbed and disturbed soil samples were collected in the 0-0.10 and 0.10-0.20 m
layers to evaluate the water-dispersible clay (WDC), bulk density (BD), total porosity (TP),
macroporosity (Ma), microporosity (Mi), aeration capacity (AC), water retention, plantavailable water capacity (PAWC), relative field capacity (RFC), particle size and chemical
soil properties (pH, Al3+, Ca2+, Mg2+ and OC). The WDC contents in the 0-0.10 m layer
increased with soil disturbance, but were not influenced by liming. When liming was
performed on surface, there were reductions in BD, Ma and AC and increases in TP and
Mi in the 0-0.10 m layer. With liming, there was an increase in soil water retention in the 00.10 layer, regardless of the corrective mode of application, but these effects were more
pronounced when lime was applied on surface. Incorporated liming reduced the PAWC,
but not the RFC. For the 0.10-0.20 m layer, limestone incorporated with plowing and
harrowing increased BD and reduced TP, Ma and AC. For this layer, water retention was
somewhat affected by liming. Changes in soil physical attributes were caused mainly by
the reduction in soil pH, the precipitation of Al3+ in the soil solution and replacing it ion the
exchange complex Ca2+ and Mg2+.
Keywords: Soil acidity; clay dispersion; cation exchange capacity; outer-sphere surface
complex; soil management.
55
TENSILE STRENGTH OF AN ALFISOL UNDER DIFFERENT DOSES OF RICE HUSK
ASH
Ivana Kruger Tuchtenhagen1, Cláudia Liane Rodrigues de Lima2, Eloy Antonio Pauletto2,
Ledemar Carlos Vahl2, Lizete Stumpf2, Rodrigo Brum de Paiva2
Ivana.kruger@bol.com.br; Universidade Federal de Pelotas – UFPEL.
1
Rice husk comes from the rice milling process. The rice husk due to its high calorific value
is being to replace wood as an energy source in rice processing industries. The byproduct
generated in this burning is called rice husk ash (RHA). To obtain a rational use of RHA in
agricultural soils, this study aimed to verify the effect of different doses of RHA on the soil
structural quality. We evaluated the tensile strength (TS) of the aggregates, bulk density
(Bd) and the total organic carbon content (TOC) of an Alfisol. The study was conducted at
the Agricultural Center of Palma, belonging to the Federal University of Pelotas (UFPel)
located in Capão do Leão municipality (RS - Brazil). The experiment consisted of five
doses of RHA (0, 20, 40, 80 and 120 t ha-1) in a randomized block design with four
replicates. The samples were collected in the 0.00 to 0.10 m soil layer. For evaluation of
TS were used disturbed soil samples (400 samples per treatment) totaling 2.000
aggregates. To quantify the TOC additional samples were selected. The soil BD was
determined by collecting preserved samples using soil core (12 per treatment), totaling 60
samples. The results were submitted to variance analysis and Tukey test (5%). The results
of this study allowed the observation that treatment without addition of RHA (0 t ha -1) had
the highest TS, Bd and the lowest TOC values. The fact of this treatment present a higher
Tensile Strength (TS) value can be associated with the presence of more stable
aggregates and not to the rice husk ash (RHA) addition to the soil. The higher TS in this
treatment can ensure greater stability to the soil’s pore system when different stresses’
levels are applied and hence it becomes beneficial to the plants. Meanwhile, the higher TS
value in this treatment can be related to the short-term action of the RHA in the
improvement of the soil structure quality. The minimum TS value was obtained in the 120 t
ha-1 treatment and it can possibly be assigned to the higher concentration of RHA and,
consequently, higher concentration of Total Organic Carbon (TOC) in this treatment. In
addition, there was no statistical difference between treatments 20, 40 and 80 t ha -1 and
this can be associated to a potential homogenization between those treatments. However,
the values found were, in average, lower than those in the treatments without RHA
addition and higher than those in the 120 t ha -1 treatment. The highest TS values between
those three treatments were found in the T2 and it can be related to the RHA
concentration in it. The 120 t ha-1 treatment had the lowest Bulk Density (BD) value and
the highest TOC. It was observed that as the RHA content increased, the TS and BD
decreased and the TOC increased. Those physical attributes can be efficient when
evaluating the soil structure quality with RHA. Though, more research is needed in this
field so that the critical values for those physical attributes that are related to the ideal plant
growth can be defined for different soil types.
Keywords: Agricultural waste; structural quality; total organic carbon.
56
VARIABILITY AND SPATIAL DEPENDENCE OF PHYSICAL ATTRIBUTES OF AN
OXISOL UNDER DIFFERENT ROW SPACING CONFIGURATIONS OF SUGARCANE
Wildon Panziera¹, Cláudia Liane Rodrigues de Lima, Sergio Delmar dos Anjos e Silva,
Eloy Antonio Pauletto, João Roberto Pimentel, Leonir Aldrigi Dutra Junior
¹D.Sc. student on Graduate Program in Management and Conservation Soil and Water - Federal University of Pelotas. E-mail:
panziera2@yahoo.com.br
The sugarcane is a renewable energy source that plays an important role economic in
Brazil. The harvest of sugarcane migrated from the traditional system of harvest to the
mechanical harvesting of chopped cane. However, mechanization has brought some
negative aspects such as soil compaction. The use of combined row spacing can mitigate
soil compaction. The aim of study was to evaluate the influence of mechanical harvesting
in the variability and spatial dependence structure of the physical attributes of an Oxisol
under three configurations of row spacing of cane sugar. The experiment was established
in Porto Xavier, RS, Brazil in August 2012, where three types of row spacing were
evaluated: simple row spacing (1.5m), dual combined (0.4x1.7m) and triple combined
(0.3x0.3x1.5m). Soil samples were collected from the 0-0.20 m layer in January 2013,
during the first growth cycle of sugarcane, and in August 2013 (after harvest) along a
transect of 50 meters lenght adjacent to line of culture for each one of the three types of
row spacing. The following soil attributes were determined: Bulk density (BD), total soil
porosity (TP), soil macroporosity (Ma) and microporosity (Mi), soil penetration resistance
(PR), volumetric content at field capacity (θCC) and at permanent wilting point (θPWP)
and available water capacity (AWC). The data were submitted to a descriptive analysis
and an autocorrelation study to verify the spatial dependence structure. After the event of
mechanical harvesting, the means and medians of TP, Ma and AWC were reduced, with
an increasing in BD and PR in three row spacings. The row spacing simple submitted the
largest reductions of TP, MA e AWC and the largest increments of BD and PR, followed by
the row spacing triple combined and dual combined, respectively. The coefficients of
variation (CV) of TP, BD, θCC, θPWP and PR were lower in the single spacing after
harvest. CV increased for TP, Ma, Mi, BD θCC, θPWP and PR in dual combined row
spacing after harvest. The minimum value of PR was higher after harvest, with an increase
of 198, 148 and 83% in triple combined, simple and dual combined row spacing,
respectively. There were changes in the spatial dependence structure of physical
attributes in three types of row spacing after harvest. These changes were more
pronounced in simple row spacing, where all attributes were spatially dependent before
harvest. After harvesting the spatially dependence of the soil attributes were not more
observed,. The Mi, θCC, θPWP, AWC and PR were spatially independent after harvest in
dual combined row spacing. Therefore, dual combined row spacing had the lowest impact
of mechanized harvesting of sugarcane on the mean, median and CV of the soil physical
attributes. The triple combined row spacing was the one with the lowest influence of
mechanical harvesting about the dependence structure spatial.
Keywords: Saccharum spp.; soil physics; spatial variability.
57
VARIABILITY OF SOIL HYDRAULIC PARAMETERS AND ITS IMPACT ON AGROHYDROLOGICAL MODEL PREDICTIONS
Thalita Campos Oliveira1, Quirijn de Jong van Lier2
email:thalita.oliveira@usp.br; 2qdjvlier@usp.br. Center for Nuclear Energy in Agriculture – University of São Paulo (CENA/USP).
1
The soil plays an important role in the hydrological cycle and in water flows in soil-plantatmosphere system. Many hydrological models have been developed to increase
understanding of the involved processes and to improve predictions. One of these models
is the SWAP model (Soil-Water-Atmosphere-Plant) which performs simulation of transport
of water, solutes and heat in saturated and unsaturated soil as well as their interaction with
plant development. To simulate soil water movement, SWAP uses soil hydraulic properties
(retention and conduction) employing the Richards equation. Input data requirement is
high, especially for the parameters that define soil hydraulic properties. These parameters
are subject to natural soil variability. In this study we aimed to analyze the impact of the
variability of soil hydraulic parameters on the prediction of water balance components
through a stochastic process using SWAP. Hydraulic properties (soil water retention and
hydraulic conductivity) will be determined in undisturbed soil samples (metal rings of 5 cm
diameter and 3 cm height) with a large number of repetitions and Van Genuchten model
parameters α, n, θ, θr, θs and Ksat will be determined. Then, using a statistical resampling
method (bootstrap), the frequency distribution of these parameters will be defined and
three representative population sizes will be chosen. Using the three population sizes, the
frequency distribution of accumulated evapotranspiration, deep drainage and surface
runoff will be determined by a stochastic procedure with the SWAP model, running the
model for a great number of stochastic realizations of parameter values (order of 10 4
times). The results of the stochastic analysis will reflect the sensitivity of the model to input
parameters variability. The obtained information will contribute with a better understanding
of the impact of hydraulic parameters variability on water balance components estimated
by hydrological models.
Keywords: Soil variability; SWAP Model; bootstrap analysis; stochastic process.