Inoculating wheat seeds with nitrogen-fixing bacteria such as Azospirillum brasilense may be beneficial to the crop and reduce the need for N application. Nevertheless, few studies have measured the benefit of this practice on irrigated wheat with the expectation of high yield and demand for N. The objective of this study was to evaluate the yield and N content of irrigated wheat under different N application rates, with and without inoculation with A. brasilense. Two experiments were carried out in […]

Associated with the benefits of the no-till system for the soil, there may be the formation of a vertical gradient of fertility and a compacted layer caused by heavy farm machine traffic, which may modify the root growth of crops. The aim of this study was to evaluate the effect of rates and forms of phosphate fertilizer application and soil compaction by machine traffic on the physical properties and root system of soybeans and maize. The study was conducted in […]

Three estimates of rainfall erosivity in the State of Parana, Brazil, were carried out in the 1980s and 1990s, but none afterwards. The objectives of this study were to update information, as a fourth estimate, on rainfall annual erosivity for Parana, with rainfall data from 1986-2008; and to generate information on monthly erosivity in order to identify its seasonal distribution. We used the pluviographic and pluviometric methods of erosivity determination. The first served to revalidate previous correlation equations between erosivity […]

The spatial correlation between soil properties and weeds is relevant in agronomic and environmental terms. The analysis of this correlation is crucial for the interpretation of its meaning, for influencing factors such as dispersal mechanisms, seed production and survival, and the range of influence of soil management techniques. This study aimed to evaluate the spatial correlation between the physical properties of soil and weeds in no-tillage (NT) and conventional tillage (CT) systems. The following physical properties of soil and weeds […]

The construction of a soil after surface coal mining involves heavy machinery traffic during the topographic regeneration of the area, resulting in compaction of the relocated soil layers. This leads to problems with water infiltration and redistribution along the new profile, causing water erosion and consequently hampering the revegetation of the reconstructed soil. The planting of species useful in the process of soil decompaction is a promising strategy for the recovery of the soil structural quality. This study investigated the […]

Intensive land use can lead to a loss of soil physical quality with negative impacts on soil aggregates, resistance to root penetration, porosity, and bulk density. Organic and agroforestry management systems can represent sustainable, well-balanced alternatives in the agroecosystem for promoting a greater input of organic matter than the conventional system. Based on the hypothesis that an increased input of organic matter improves soil physical quality, this study aimed to evaluate the impact of coffee production systems on soil physical […]

Incorporation of rice straw into the soil just before flooding for water-seeded rice can immobilize mineral nitrogen (N) and lead to the production of acetic acid harmful to the rice seedlings, which negatively affects grain yield. This study aimed to evaluate the formation of organic acids and variation in pH and to quantify the mineral N concentration in the soil as a function of different times of incorporation of rice straw or of ashes from burning the straw before flooding. […]

Nitrogen accumulation in corn plant is highly influenced by N content in soil and by rate of its absorption by plant in a given growing stage. In order to compare the effects of N application methods on N accumulation and dry matter production by corn plant, an experiment was carried out in the state of Rio Grande do Sul, Brazil, over the 1998/99 growing season. Treatments consisted of two levels of water availability, one adequate to corn crop needs and […]

The use of legume cover crops contributes to soil conservation and would be an economical N source to maize. Since only winter legumes were evaluated in southern Brazil, this study was carried out to assess the effect of four intercropped summer species (Canavalia ensiformis, Cajanus cajan, Stizolobium niveum and Glycine sp.) on N supply and maize yield increase, in comparison with a control treatment, without legume cover crops. Cropping system effects on maize crop were evaluated under three mineral N […]

This study compares the chemical composition of the solution and exchange complex of soil in a 3-year-old irrigated vineyard (Vitis vinifera L., Red Globe cultivar) with that of adjacent clearing in the native hyperxerophyllic ‘caatinga’ vegetation. The soils are classified as Plinthic Eutrophic Red-Yellow Argisol; according to Soil Taxonomy they are isohyperthermic Plinthustalfs. Detailed physiographic characterization revealed an impermeable gravel and cobble covering the crystalline rocks; the relief of this layer was more undulating than the level surface. Significant higher […]