SOIL STRUCTURE UNDER IRRIGATED BEANS AND DIFFERENT SOIL MANAGEMENT PRACTICES
01/Mar/2015
Agricultural management affects soil structure, modifying soil physical properties and soil water movement. The objective of this study was to evaluate the effects of no-tillage (NT) and conventional tillage (CT) on soil structure through physical properties and pore distribution in 2-D digital images. The study was conducted in an Oxisol with a randomized block design. Soil bulk density, soil macroporosity, mean weighted diameter (MWD), saturated hydraulic conductivity (SHC), and analysis of 2-D digital images (156.25 μm2 resolution) were evaluated at […]
SHOOT DRY MATTER AND SHOOT MACRONUTRIENT ACCUMULATION IN NIGER
01/Mar/2015
Studying nutrient uptake and dry matter accumulation in plants as affected by crop developmental stages is essential to establish and assist strategies for crop fertilization. The aim of this study was to assess shoot dry matter and macronutrient accumulation in Guizotia abyssinica (niger) at different growth and development stages. A randomized block experimental design with five replications was used. Shoot samples of the plants were taken at 15, 30, 45, 60, 75, and 90 days after seedling emergence (DAE). At […]
APPRAISAL OF THE SNAP MODEL FOR PREDICTING NITROGEN MINERALIZATION IN TROPICAL SOILS UNDER EUCALYPTUS
01/Mar/2015
The Soil Nitrogen Availability Predictor (SNAP) model predicts daily and annual rates of net N mineralization (NNM) based on daily weather measurements, daily predictions of soil water and soil temperature, and on temperature and moisture modifiers obtained during aerobic incubation (basal rate). The model was based on in situ measurements of NNM in Australian soils under temperate climate. The purpose of this study was to assess this model for use in tropical soils under eucalyptus plantations in São Paulo State, […]
SEDIMENT MANAGEMENT FROM DREDGING OF AN URBAN RIVER: CASE STUDY OF THE LOWER BELEM RIVER
01/Mar/2015
Sediments were removed from the Belem River, and their uncertain destination may cause environmental damage and additional costs to the municipality. The aim of this study was to simulate the possibility of using an alternative allocation of the sediments based on Brazilian environmental law. The evaluation of destination and/or use was made from a preliminary chemical evaluation of inorganic contaminants (Cd, Pb, Cu, Cr, Ni, Ag, and Zn) and polycyclic aromatic hydrocarbons (PAHs) related to productive activities in the region. […]
LEAST LIMITING WATER RANGE IN CONSTRUCTED SOIL AFTER COAL MINING IN DIFFERENT CRITICAL LIMITS OF PENETRATION RESISTANCE AND WATER CONTENT
01/Mar/2015
In quantifying the least limiting water range (LLWR), different critical limits of resistance to penetration (RP) and moisture at field capacity (θFC) are generally used. For agricultural soils, these values are documented in the literature. However, for constructed soil after coal mining, there is a large information gap. The aim of this study was to quantify the least limiting water range of a constructed soil under different cover crops in a coal mining area in Candiota, RS (Southern Brazil), considering […]
ARBUSCULAR MYCORRHIZAL FUNGI IN SEEDLING DEVELOPMENT OF OLIVE (OLEA EUROPAEA L.) IN THE SOUTH OF MINAS GERAIS, BRAZIL
01/Mar/2015
The olive tree is a temperate climate plant, whose fructification requires low temperatures before flowering. The production of good quality seedling material is essential for establishing an orchard, and association with arbuscular mycorrhizal fungi (AMF) can be very important in this respect. In Brazil, there are no studies related to the use of AMF in olive seedling production. The aim of this study was to evaluate the effect of the use of different AMF species on the development of seedlings […]
SPATIAL VARIABILITY OF SORGHUM YIELD AND SOIL PROPERTIES IN THE REGION OF THE SAVANNA-WETLAND ECOTONE IN MATO GROSSO DO SUL, BRAZIL
01/Mar/2015
Sorghum bicolor (L.) Moech is an important high production forage crop that is increasingly used in Brazil, though still slow in replacing growing of second crop maize. Growing sorghum during the dry season would be an alternative for silage production and its use in the rainy season. However, plant growth and development will be affected if alterations occur in the texture, porosity, and structure of the soil. The objective of this study was to analyze the spatial variability and linear […]
VARIABILITY OF PHYSICAL AND CHEMICAL SOIL PROPERTIES AND PRODUCTION COMMON BEAN IN A MINIMUM TILLAGE SYSTEM WITH IRRIGATION
01/Mar/2015
Understanding the agricultural potential of a soil is often based only on interpretation by univariate analyses, and this may increase the scale of the problems when selecting appropriate soil management practices. Thus, multivariate analysis is an alternative since it is a set of procedures aimed at grouping individuals and discriminating between these groups. It also serves as an instrument for selection of variables in that those with the highest weight in the construction of the first principal components are likely […]
NUTRIENT DEMAND BY THE CARROT CROP IS INFLUENCED BY THE CULTIVAR
01/Mar/2015
Farmers must carefully choose the cultivar to be grown for a successful carrot crop. The yield potential of the cultivar may influence nutrient demand and should be known to plan for fertilization application. The aim of this study was to evaluate the cultivar effect on carrot yield and on the nutrient content and quantities allocated to leaves and roots. Three experiments were set up in two crop seasons in Rio Paranaíba, MG, Brazil. In the first season, typical summer, 10 […]
PHYSICAL, CHEMICAL, AND BIOLOGICAL QUALITY IN AN OXISOL UNDER DIFFERENT TILLAGE AND FERTILIZER SOURCES
01/Mar/2015
Soil quality (SQ) assessment is an important strategy for defining management practices and systems capable of maintaining and/or improving the sustainability of agricultural systems. Thus, the aim of this study was to evaluate changes in SQ by physical, chemical, and biological indicators in an Oxisol under different tillage systems and fertilizer sources. The study was conducted in Taquaruçu do Sul, RS, Brazil based on an experiment set up in 2009 in a randomized block design with four replications. The treatments […]