Response of one-, five-, and nine-year-old pinus taeda to NPK fertilization in southern Brazil
01/Aug/2014
In the southern highland (Planalto Sul) region of Santa Catarina, Brazil, most of the pine forests were planted without soil fertilization. Currently, many areas are in the second or third rotation, and their productivity may be limited by low soil fertility. An alternative to mitigate this problem would be fertilization in the established forest. This study was carried out with the objective of evaluating the effect of fertilization with N, P, and K at different growth stages of Pinus taeda. […]
The effects of land use and soil management on the physical properties of an Oxisol in Southeast Brazil
01/Aug/2014
Soils of the tropics are prone to a decrease in quality after conversion from native forest (FO) to a conventional tillage system (CT). However, the adoption of no-tillage (NT) and complex crop rotations may improve soil structural quality. Thus, the aim of this study was to evaluate the physical properties of an Oxisol under FO, CT, and three summer crop sequences in NT: continuous corn (NTcc), continuous soybean (NTcs), and a soybean/corn rotation (NTscr). Both NT and CT decreased soil […]
Ammonia volatilization and yield components after application of polymer-coated urea to maize
01/Aug/2014
A form of increasing the efficiency of N fertilizer is by coating urea with polymers to reduce ammonia volatilization. The aim of this study was to evaluate the effect of polymer-coated urea on the control of ammonia volatilization, yield and nutritional characteristics of maize. The experiment was carried out during one maize growing cycle in 2009/10 on a Geric Ferralsol, inUberlândia, MG, Brazil. Nitrogen fertilizers were applied as topdressing on the soil surface in the following urea treatments: polymer-coated urea […]
Variability of root traits in common bean genotypes at different levels of phosphorus supply and ontogenetic stages
01/Aug/2014
Selection of common bean (Phaseolus vulgaris L.) cultivars with enhanced root growth would be a strategy for increasing P uptake and grain yield in tropical soils, but the strong plasticity of root traits may compromise their inclusion in breeding programs. The aim of this study was to evaluate the magnitude of the genotypic variability of root traits in common bean plants at two ontogenetic stages and two soil P levels. Twenty-four common bean genotypes, comprising the four growth habits that […]
Influence of the grazing height of ryegrass and oat on the physical properties of an Oxisol after seven years of crop-livestock system
01/Aug/2014
The pressure applied by animal hooves can lead to soil surface compaction in a crop-livestock system (CLIS), with effects on soil physical quality. The hypothesis of this study was that the trampling of animals as a result of grazing on oat and ryegrass crops in a Latossolo Vermelho distroférrico (Oxisol) under no-tillage in a CLIS degrades soil physical quality. The aim of this study was to evaluate the effect of different grazing heights on soil bulk density (BD), total porosity […]
Three-dimensional interpolation of soil data: fertility and pedomorphological features in southern Brazil
01/Aug/2014
The graphical representation of spatial soil properties in a digital environment is complex because it requires a conversion of data collected in a discrete form onto a continuous surface. The objective of this study was to apply three-dimension techniques of interpolation and visualization on soil texture and fertility properties and establish relationships with pedogenetic factors and processes in a slope area. The GRASS Geographic Information System was used to generate three-dimensional models and ParaView software to visualize soil volumes. Samples […]
Analysis of NPK fertilizers inspected by mapa from 2008 to 2010
01/Aug/2014
Brazil is the fourth largest consumer of fertilizers in the world. Among these, bulk blends fertilizers are the most consumed in the country. After updating of Brazilian legislation in regard to fertilizers in 2004, many producers claim that there was an excessive increase in the strictness of legislation concerning inspection of nutrient levels in those products. Within this context, the objective of this study was to provide an exploratory and descriptive statistical analysis to the data gathered by MAPA (Ministry […]
Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast
01/Aug/2014
The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 […]
Chemical and mineralogical changes in a Brazilian Rhodic Paleudult under different land use and managements
01/Aug/2014
Changes in land use and management can affect the dynamic equilibrium of soil systems and induce chemical and mineralogical alterations. This study was based on two long-term experiments (10 and 27 years) to evaluate soil used for no-tillage maize cultivation, with and without poultry litter application (NTPL and NTM), and with grazed native pasture fertilized with cattle droppings (GrP), on the chemical and mineralogical characteristics of a Rhodic Paleudult in Southern Brazil, in comparison with the same soil under native […]
Spatial variability of the properties of cohesive soils from eastern Maranhão, Brazil
01/Aug/2014
The national and international demand for maps of soil properties has increased. The aim of this study was to characterize cohesive soils and associate their variability of particle size, chemical properties, and color to different landforms in agricultural areas and native vegetation using geostatistical techniques. To set up the experiment, we selected three areas of soil consisting of an area planted to soybeans and, contiguous to it, another area with plant cover remaining from three types of cerrado (tropical savanna), […]
