For every type of soil, the water retention curve is specific and depends on several soil features. This study was carried out to evaluate the influence of soil attributes on water retention in Red Latosol (Haplustox) and Red Latosol (Eutrustox) under different management and use systems. The use systems were: cotton, sugar-cane and woods. The granulometric composition, bulk density, organic matter, Fe2O3 and Al2O3 contents, as well as the water retention curve were determined for soil samples from different depths […]

The objective of this work was to propose a methodology for land evaluation based on planting information, soil data extracted from a soil survey in a scale 1:50,000, and estimate of climatic risk, using a geographic information system (GIS). The reference area was the Jardim watershed, in the Federal District (Brazil). A water balance model was used to simulate the climatic risk for the corn crop (Zea mays L.), at nine different planting dates. Quantitative values for corn productivity parameters […]

The Southern part of Minas Gerais State is an important coffee producer region in Brazil. Though coffee yields are still quite low. Plant tissue analysis based on sufficiency ranges as well as the Diagnosis and Recommendation Integrated System (DRIS) are important tools for the correct use of fertilizers. However, as local standards are not yet obtained for Coffea arabica in that region, recognition as well as calibration of reference values used elsewhere are called for. Objectives of this study were: […]

Heavy metal components in solid urban waste composts have been one of the main causes of concern in relation to its use on agricultural soils. On this background, a field experiment was carried out to study the effects of successive compost application on Cd, Cr, Cu, Ni, Pb, and Zn contents in a Typic Hapludox, in sugarcane plants, as well as on the phytoavailability of these metals as assessed by chemical extractors (DTPA, 0,1 mol L-1 HCl and Mehlich-3). The […]

This study presents an alternative procedure for the extraction of micronutrients from soil samples for fertility evaluation. Samples from an interdisciplinary program for soil analysis with different physical and chemical characteristics were subjected to DTPA extraction using focused microwave radiation energy. The microwave-assisted procedure (10 min) proved to be remarkably time-saving for Cu, Mn, and Zn extraction when compared to the time consume of conventionally prepared samples (120 min), using mechanical stirring at room temperature. The development of a single […]

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 soil water retention curve plays a fundamental role in the development of studies on the dynamics of soil water, modeling of physical soil processes and plant growth. The retention curve is usually obtained by simultaneously measuring water content (θ) and soil water potential (ψ) in a single sample. An alternative procedure is to use several samples per ψ to describe the retention curve. The use of this procedure requires that the variation factors which exist among the samples are […]

Brasilia’s urban growth has caused the increase of domestic sewage sludge, production generating a large volume of biosolid – a final product of sludge treatment – deposited at the Companhia de Saneamento de Brasilia (CAESB) sewage treatment plants. Although there is still a lack of technical data on health, environmental safety and economic viability, it has been used as a soil amendment and fertilizer by farmers in the neighbouring areas. The biosolid produced at one of the sewage treatment plants […]

The Guaratuba watershed is located at the “Parque Estadual da Serra do Mar” and has its headwaters in the Atlantic plateau. The area has a gneissic bedrock in a parallel hilly relief with high slope gradient, covered by the Atlantic forest consisting mostly of low size trees. The climate is humid tropical with rainfall of 2,000 mm year-1, with no dry season. The predominant soils are Red Yellow Argisol (Typic Kandiudults or Paleudults and Typic or Lithic Hapludults) and Haplic […]

Soil and water loss data under natural rainfall in Lages, Santa Catarina State (Brazil), from November 1992 to October 1998, were utilized to calculate the soil loss ratio (SLR) and C factor for the Universal Soil Loss Equation (USLE) under three soil tillage systems for corn and oat in rotation with other crops. The studied treatments were: plowing followed by disking twice (P + D), chiseling plus disking (C + D) and no-tillage (NT)/direct sowing, cultivated with corn (Zea mays) […]