Volume 38, Number 5, 2014

In recent years, new technologies have been developed to reduce N losses when using urea as a source of this macronutrient. The use of fertilizers with acidic features can reduce ammonia losses from volatilization when combined with urea. The objective of this study was to assess ammonia losses from sources of N with or without coating and/or incorporation of S and bentonite. These fertilizers were applied to the surface of a Haplic Planosol contained in trays (0.1 m2 area and […]

In tropical regions, the damage caused to soil by rainwater, i.e., soil erosion, is the most significant form of soil degradation. In Brazil, eucalyptus plantations are mainly located in ecosystems sensitive to anthropogenic disturbances for reasons such as the occurrence of plantations in soils with low clay contents, soils with low natural fertility, and most plantations being established on areas previously occupied by agriculture or by degraded pastures. Thus, the need arises for understanding the processes that control water erosion […]

Agricultural production systems that include the production of mulch for no-tillage farming and structural improvement of the soil can be considered key measures for agricultural activity in the Cerrado region without causing environmental degradation. In this respect, our work aimed to evaluate the chemical and physical-hydric properties of a dystrophic Red Latosol (Oxisol) in the municipality of Rio Verde, Goias, Brazil, under different soil management systems in the between-crop season of soybean cultivation five years after first planting. The following […]

The soil cover by crop residues dissipates the kinetic energy of raindrops, while, the surface roughness dissipates the kinetic energy of runoff, therefore, both store water and retain sediments on surface, decreasing water erosion. The objective of this study was to determine the persistence and the influence of crop residues and surface roughness in cultivated soil on soil and water losses, compared to bare and uncovered soil under the following treatments: i) cultivated soil: covered by ryegrass mulch (Lolium multiflorum), […]

Pig production in the State of Santa Catarina, Brazil, is responsible for many jobs in the rural area and it has great social and economic importance. This study was carried out from March to September 2012 to evaluate the influence of a single application of pig slurry to an Ultisol (Nitossolo Bruno aluminoférrico húmico) soil on losses of water, soil, P and K due to water erosion. Treatments consisted of application rates of 0 (zero), 50, 100, and 200 m3 […]

Water infiltration in the soil is an important hydrological process that occurs at the interface of the soil-atmosphere system; thus, the soil management practice used has a strong influence on this process. The aim of this study was to evaluate water infiltration in the soil and compare equations for estimating the water infiltration rate in an Ultisol after harvesting common bean (Phaseolus vulgaris L.) under simulated rainfall. Field tests with a rainfall simulator were carried out in three soil management […]

A significant quantity of nutrients in vineyards may return to the soil each year through decomposition of residues from cover plants. This study aimed to evaluate biomass decomposition and nutrient release from residues of black oats and hairy vetch deposited in the vines rows, with and without plastic shelter, and in the between-row areas throughout the vegetative and productive cycle of the plants. The study was conducted in a commercial vineyard in Bento Gonçalves, RS, Brazil, from October 2008 to […]

Studies testing the High Energy Moisture Characteristic (HEMC) technique in tropical soils are still incipient. By this method, the effects of different management systems can be evaluated. This study investigated the aggregation state of an Oxisol under coffee with Brachiaria between crop rows and surface-applied gypsum rates using HEMC. Soil in an experimental area in the Upper São Francisco region, Minas Gerais, was studied at depths of 0.05 and 0.20 m in coffee rows. The treatments consisted of 0, 7, […]

Glyphosate is a systemic post-emergent herbicide of the non-selective organophosphate group widely used in apple orchards in the South of Brazil. It may have adverse effects on beneficial soil microorganisms. The aim of this study was to evaluate the biodegradability of glyphosate by soil microbiota in apple orchards with different histories of application of the product. For that purpose, soil samples from the region of Vacaria, Rio Grande do Sul, were used, with the biodegradation of glyphosate being evaluated by […]

The use of sewage sludge in agriculture is a sound alternative for nutrient recycling, but the concern over increase in soluble chemical species from mineralization of organic matter remains. The study of the soil solution is a valuable tool for understanding the availability of nutrients and for assessing the risk of soil and water contamination. For such studies, where the number of parameters examined is usually more than 10, the use of multivariate analysis tools, such as principal component analysis […]