Volume 32, Number 5, 2008
Soil nitrate as affected by pig slurry application under no-till corn
01/Oct/2008
The application of animal manure to the soil, particularly those generated in pig farms, has become an increasingly common practice in southern Brazil. However, depending on the dose applied, there is a risk of nutrient losses, mainly nitrate (NO3–), to the water courses through leaching and runoff, and to the atmosphere as N-oxide emissions. The objective of this work was to evaluate the accumulation and displacement of N-NO3– in the soil after pig slurry application in no-tillage corn. The doses […]
Analysis of rainfall erosivity associated to pluvial precipitation patterns in the Ribeirão das Lajes region, Rio de Janeiro state, Brazil
01/Oct/2008
The rainfall characteristics determine erosivity, which is an important factor in the cause – effect relationship in soil erosion. The characterization of rainfall is therefore of fundamental importance for conservation planning. The present study aimed to evaluate the distribution of rainfall characteristics (depth, duration, kinetic energy, maximum intensity in 30 min) and erosivity indexes (EI30 and KE > 25) in relation to the months of the year and to precipitation patterns for a series of pluviographic data in the region of Ribeirão das […]
Simulation of water erosion spatial variability in a watershed representative of oxisols in southern Minas Gerais State
01/Oct/2008
Simulation of water erosion spatial distribution is an important tool for soil conservation planning in watersheds, being an important application of the Universal Soil Loss Equation (USLE) using interpolation principles, such as geostatistics. This study aimed to simulate spatial distribution of water erosion in a watershed of the Alto Rio Grande (MG) region, applying geostatistical tools for mapping, considering different land use scenarios. Water erosion was estimated by the USLE applied to grid cells, weighing pedologic units and land use […]
Changes in hydro- physical attributes of a typic haplustox in the Cerrado of Mato Grosso state under different forms of soil use
01/Oct/2008
The search for production forms that meet the increasing worldwide demands, maintaining the potential of the natural resources and in a systemic view of the social, economic and environmental sustainability, must be everybody’s interest and above all a concern of professionals of agrarian sciences. Aiming at a contribution in this direction, the effect of no-till and cultivated pasture production on the physical and water properties of a Typic Haplustox (Distrophic Red-Yellow Latosol) were evaluated. The study was conducted on a […]
Reduction of water erosion in three soil management systems in an Inceptisol of the Planalto Sul-Catarinense region – Brazil
01/Oct/2008
Tillage is one of the most important components of soil management in the process of crop production, normally used to create a favorable environment for sowing, seed germination and plant development. In addition, it is mainly determinant for the or surface soil physical conditions that will ultimately determine the erosion and the effectiveness of runoff reduction of the various soil management systems used to establish a given crop, in a given place. Considering these aspects, a field study under natural […]
Solubilization of Patos de Minas and Arad rock phosphate in two flooded soils
01/Oct/2008
Differences in grain yield were not observed in experiments with paddy rice when comparing soluble phosphates and rock phosphate as phosphorus sources. However, chemical changes in flooded soils such as increases in pH and phosphorus and calcium levels in the soil solution probably decrease the dissolution of rock phosphates in flooded soils. The current work was therefore carried out with the objective of studying the solubilization of phosphate rocks in flooded soils. Two experiments, conducted in a random block design […]
Paclobutrazol transport in soil columns
01/Oct/2008
Paclobutrazol (PBZ) is a post-emergence plant growth regulator used in agricultural systems with the objective of vegetative control growth, thereby increasing the reproductive capacity of the plant. This growth regulator remains active in the soil for several years being detrimental to subsequent tillage and contamination of groundwater through leaching. The objective of this work was to study the mechanisms involved in the transport and sorption of PBZ in an Ultisol and a Vertisol, both of the São Francisco Valley, Brazil. […]
Mobility of paclobutrazol in an intensively used sandy loam soil under mango in northeastern Brazil
01/Oct/2008
In Mango cultivation under Brazil conditions paclobutrazol (PBZ), a growth regulator, is very used. However it is not yet well known about the leaching potential of PBZ in these soil conditions. The objectives of this study were to evaluate sorption and mobility of paclobutrazol (PBZ), a growth regulator of the chemical group triazol, in a sandy loam soil found in the sub-mid region of the San Francisco River valley, where mango cultivation is intense. The sorption study was based on […]
Distribution and forms of zinc in soils from Vazante, state of Minas Gerais (Brasil)
01/Oct/2008
Soil contamination is nowadays a problem that requires detailed investigation in order to set up criteria for distinction between natural anomalies and antropogenic contribution. This work was carried out to evaluate zinc distribution and fractions, aiming to identify the origin of high Zn content in soils around mining areas in the Vazante county -MG (Brazil). Soil profiles were sampled in mined areas, and in upslope and downslope positions at depths of 0-2, 2-5, 5-10, 10-20, 20-50, 50-100 and 100-150 cm. A […]
Cadmium, chromium, lead and zinc in maize plants and oxisol after nine annual applications of sewage sludge
01/Oct/2008
A major limitation for using sewage sludge in agriculture is the risk of soil contamination with heavy metals and their possible transference to humans via food chain. The objective of this study was to evaluate the soil content of Cd, Cr, Pb, and Zn by two digestion methods (HNO3 + H2O2 + HCl and HClO4 + HF) in maize plants grown on a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years, and the effects on dry matter […]
