Cadmium may be added to the soils through tire residues, oils, urban waste, sewage sludge and phosphated fertilizers. It is easily absorbed and translocated by plants and can potentially harm human health. The objectives of this work were to study cadmium adsorption in surface and subsurface horizons of two highly weathered soils with different textures: Anionic “Rhodic” Acrudox (RA) and Anionic “Xanthic” Acrudox (XA), representing extreme conditions in the scale of weathering and exhibiting a predominant balance of positive charge […]

Black oats and common vetch are the main winter cover crops in southern Brazil. Grass-legume bicultures grown as winter cover crops are rarely used by farmers, although they can provide a more balanced biomass C/N ratio than single crops, besides erosion control and N supply to corn. In order to evaluate this hypothesis, this work was carried out on a Hapludalf with a sandy-loam texture, located at the Federal University of Santa Maria (RS). The treatments comprised different seeding density […]

The understanding of the physics of root aeration may allow a more correct and dynamic estimate of the minimum air-filled porosity, providing a more complete estimate of the plant behavior in relation to soil water content and gas conductivity of the soil. The aeration process is physically described in this paper to show that the result may be useful for estimating minimum air-filled porosity as a function of the total soil porosity, depth to be aerated and oxygen consumption rate. […]

The direct consequences of inadequate soil management are erosion, productivity reduction and loss of sustainability. This study aimed to evaluate the resistance to penetration and permeability of soil to water under management systems used in the cerrado region. The study was conducted at Embrapa Corn and Sorghum, in Sete Lagoas (MG), using a cerrado phase, very clayey, typic dystrophic Red Latosol (Acrusthox). The native cerrado provided lower soil density, higher macroporosity, higher total volume of pores, and consequently, smaller resistance […]

The term “cohesive” has been used in Brazil to distinguish sub-surface soil horizons that have hard, very hard or extremely hard consistency when the soil is dry, and friable when the soil is wet. Australian soils with similar behavior were identified as hardsetting. Researchers have indicated that many soils in Africa and other semi-arid regions can also be characterized as hardsetting. Based on the definition and characteristics of the hardsetting soils, it is believed that “cohesive” soils of the Low […]

The purpose of this work was to obtain the retarding factor (R) and the dispersion-diffusion coefficient (D) for chromium (III) in two highly weathered soils collected in São Paulo, Brazil. The influence of the following factors on these two parameters were analyzed: textures, pH and soil organic matter. Samples of the A and B horizons of two soils were used, differing significantly in organic matter contents (a) a Typic Eutrorthox (LVe) and (b) a Typic Haplorthox (LVd). Soil pH of […]

The aim of this work was to study the extraction of available boron using hot water and CaCl2 5 mmol L-1, and a microwave oven as the heating device. Boron was determined using azomethine-H. The influence of some soil characteristics on the performance of the extractants, was also studied. Corn plants were grown in a greenhouse, in a completely randomized block design, using 17 soil types and 6 B rates (0.0, 0.15, 0.30, 0.60, 0.90 and 1.5 mg dm-3) in a factorial with three […]

Mixed plantations of eucalypt and acacia can be beneficial from both the ecological and economic viewpoints, as they increase the biological diversity and reduce the costs of nitrogen fertilization. This trial had the objective to evaluate the effect of mixed plantations of Eucalyptus saligna (Smith) and Acacia mearnsii (De Wild) on soil and stand characteristics. The experiment was carried out on a Red Yellow Latosol, in the state of Rio Grande do Sul, Brazil, and the treatment consisted of pure […]

The direct consequences of inadequate soil management are erosion, reduction of productivity and loss of sustainability. The indicators of soil structure quality are important tools for evaluating sustainability of management systems. This study aimed to evaluate the aggregation of typic dystrophic Red Latosol (Oxisol) under different management systems at cerrado region in Sete Lagoas, Minas Gerais, Brazil. Among the studied management systems, no-tillage presented higher percentage of aggregates in the > 2 mm class, smaller percentage in the < 2 mm and < 1 mm classes, […]

High acidity predominates in southeastern and midwestern Brazilian soils, where the largest area of sugar cane plantations is concentrated. Large amounts of slag, a steel-industry residue containing nutrients such as calcium and magnesium and acting as acidity corrective agents, are also present in the region. This study aimed to evaluate different base saturation levels using slag as a soil corrective agent. This material was compared to calcitic limestone to analyze acidity neutralization and certain chemical soil properties, as well as […]