Temporal Variation of Soil Physical Quality under Conventional and No-Till Systems
04/abr/2018
ABSTRACT: Determination of soil physical quality (SPQ) is very important because it is related to many important soil processes. However, it is not clear which indicators should be considered in this evaluation, and information about temporal variation of SPQ under different soil tillage systems is scarce. The aim of this study was to determine the effects of no tillage (NT) and conventional tillage (CT) on temporal variation of capacity SPQ indicators [bulk density (BD), macroporosity (Pmac), air capacity (AC), plant […]
Reference Values of Soil Quality for the Rio Doce Basin
04/abr/2018
ABSTRACT: The great geological and soil variation in the state of Minas Gerais, Brazil, indicates the need for regional studies to understand the geochemical background of soils. The Rio Doce Basin became a priority area for geochemical background determination after the rupture of the tailings dam of Fundão in 2015. In this context, the objectives of this study were to propose Reference Values of Soil Quality in the Rio Doce Basin, to define variables that can predict metal(loid) concentrations in […]
Prediction of Topsoil Texture Through Regression Trees and Multiple Linear Regressions
04/abr/2018
ABSTRACT: Users of soil survey products are mostly interested in understanding how soil properties vary in space and time. The aim of digital soil mapping (DSM) is to represent the spatial variability of soil properties quantitatively to support decision-making. The goal of this study is to evaluate DSM techniques (Regression Trees – RT and Multiple Linear Regressions – MLR) and the ability of these tools to predict mineral fraction content under a wide variability of landscapes. The study site was […]
Metal-Resistant Rhizobacteria Change Soluble-Exchangeable Fraction in Multi-Metal-Contaminated Soil Samples
23/mar/2018
ABSTRACT There is a complex interaction between various components of the soil ecosystem, including microbial biomass and soil chemical contaminants such as heavy metals and radionuclides, which may greatly affect the efficiency of bioremediation techniques. The aim of this study was to investigate microbial capacity to change pH, changes in the metal soluble-exchangeable fraction, and effects of initial heavy metal contents on soil samples in microbial solubilization/immobilization capacity. The soil samples used in this study were collected at a known […]
Effectiveness of Arsenic Co-Precipitation with Fe-Al Hydroxides for Treatment of Contaminated Water
23/mar/2018
ABSTRACT Wastewater treatment is a challenging problem faced by the mining industry, especially when mine effluents include acid mine drainage with elevated arsenic levels. Iron (hydr)oxides are known to be effective in removal of As from wastewater, and although the resulting compounds are relatively unstable, the presence of structural Al enhances their stability, particularly under reducing conditions. The purpose of this study was to assess the effectiveness of Al-Fe (hydr)oxide co-precipitates for the removal of As from wastewater and to […]
Temporal and Spatial Uncertainty of Erosion Soil Loss from an Argisol Under Sugarcane Management Scenarios
23/mar/2018
ABSTRACT The identification of erosion-susceptible areas is fundamental for the adoption of soil conservation practices. Thus, the best way to estimate the spatial pattern of soil erosion must be identified, in which the process uncertainties are also taken into consideration. The purpose of this study was to evaluate the spatial and temporal uncertainty of soil loss under two scenarios of sugarcane harvest management: green cane (GC) and burnt cane (BC). The study was carried out on a 200-ha area, in […]
Spatial Variability of Soil Fauna Under Different Land Use and Managements
19/mar/2018
ABSTRACT Geostatistics allows the evaluation of the distribution pattern of data with high spatial variability in agricultural systems. This study aimed to evaluate the spatial variability of biological diversity indices of soil fauna under different land (agriculture and forest). Samples were collected in seven areas (millet, soybean, corn, eucalyptus, pasture crops, and preserved and disturbed Cerrado), in Maranhão state, Brazil. The soil fauna was caught trapped in pitfall traps, installed 3 m away from each other. In each area, 130 […]
Spatial Disaggregation of Multi-Component Soil Map Units Using Legacy Data and a Tree-Based Algorithm in Southern Brazil
02/mar/2018
ABSTRACT Soil surveys often contain multi-component map units comprising two or more soil classes, whose spatial distribution within the map unit is not represented. Digital Soil Mapping tools supported by information from soil surveys make it possible to predict where these classes are located. The aim of this study was to develop a methodology to increase the detail of conventional soil maps by means of spatial disaggregation of multi-component map units and to predict the spatial location of the derived […]
Identification of Heavy Metals in Crystals of Sand and Silt Fractions of Soils by Scanning Electron Microscopy (SEM EDS/WD-EPMA)
02/mar/2018
ABSTRACT Studies of heavy metals are concentrate on clay fractions, but coarser fractions of the soil can constitute significant sources of structural forms of heavy metals. The aim of this study was to evaluate the occurrence of heavy metals in the structure of minerals of the sand and silt fractions of soils from three different parent materials (metamorphic rocks and granite) in southern Brazil using SEM/EDS – Scanning Electron Microscopy with Energy Dispersive Spectroscopy and with WD-EPMA – with Wavelength […]
Relationship Among Crop Systems, Soil Cover, and Water Erosion on a Typic Hapludox
02/mar/2018
ABSTRACT Several soil conservation practices are used to reduce water erosion and ensure sustainable agriculture. An effective crop management practice is intercropping, in which two or more crops with different architectures and vegetative cycles are grown simultaneously in the same area. We hypothesized that intercropping of corn and jack-bean increases soil cover and reduce soil erosion by water in comparison to monocropping. The objective of this study was to evaluate the effects of different crop systems on soil cover and […]