Cover Crops and Nitrogen Fertilization Effects on Nitrogen Soil Fractions under Corn Cultivation in a No-Tillage System
13/Apr/2016
ABSTRACT The use of cover crops has recently increased and represents an essential practice for the sustainability of no-tillage systems in the Cerrado region. However, there is little information on the effects of nitrogen fertilization and cover crop use on nitrogen soil fractions. This study assessed changes in the N forms in soil cropped to cover crops prior to corn growing. The experiment consisted of a randomized complete block design arranged in split-plots with three replications. Cover crops were tested […]
Soil Macrofauna and Physical and Chemical Properties under Soil Management Systems in the Santa Catarina Highlands, Brazil
01/Dec/2015
ABSTRACT Soil use can change processes such as soil organic matter decomposition, nutrient cycling, and particle aggregation, which, in turn, influence the occurrence of macrofauna. The objective of this study was to relate land use systems to their effects on the distribution of soil macrofauna groups, as well as their relation to soil physical and chemical properties. The land use systems evaluated were native forest, an Eucalyptus plantation, pasture, a crop-livestock integration area, and a no-tillage crop area. Samples were […]
SPATIAL VARIABILITY OF SOIL PROPERTIES IN AN AGRARIAN REFORM SETTLEMENT
01/Dec/2015
ABSTRACT The study of soil chemical and physical properties variability is important for suitable management practices. The aim of this study was to evaluate the spatial variability of soil properties in the Malhada do Meio settlement to subsidize soil use planning. The settlement is located in Chapadinha, MA, Brazil, and has an area of 630.86 ha. The vegetation is seasonal submontane deciduous forest and steppe savanna. The geology is formed of sandstones and siltstones of the Itapecuru Formation and by […]
Occasional Soil Turnover and Liming in a Clayey Oxisol Under a Consolidated No-tillage System
01/Sep/2015
ABSTRACT Accumulation of nutrients and surface compaction have been reported after a long time under a no-tillage system. The aim of this study was to evaluate soil chemical properties, bulk density, and crop yield following a single mechanical intervention associated with liming in a clayey Oxisol under a NT system for 17 consecutive years in Pato Branco, southwestern Paraná, Brazil. A randomized block experimental design was used in a split-plot arrangement, with plowing and harrowing of the soil in the […]
Soil Compaction Curve of an Oxisol Under Sugarcane Planted After In-row Deep Tillage
01/Sep/2015
ABSTRACT Soil tillage that maintains the productivity of sugarcane plantations, providing an area for the root development and without traffic on crop rows, has given rise to new technologies in rural areas. The purpose of this study was to evaluate the soil physical properties in two sugarcane plantations, one of which was prepared with deep tilling and the other with conventional tillage. The experiment was conducted in Lençóis Paulista, São Paulo State. Soil penetration resistance and relative density were analyzed. […]
Grazing Height of Brachiaria and Stocking Rate Limited by Soil Physical Properties Three Years Into an Integrated Soybean Crop-Livestock System
01/May/2015
Management of forage grazing height by cattle may compromise soil physical properties. The objective of this study was to evaluate the influence of grazing height of brachiaria (Urochloa ruziziensis) and the average stocking rate, after three years into an integrated soybean crop-livestock system, in the physical attributes of a Haplorthox (Rhodic Ferralsol). A randomized complete block experimental design with three replications was used. Five treatments were evaluated in 1 ha experimental plots: grazing heights of 10, 20, 30, and 40 […]
Soil Aggregation, Organic Carbon Concentration, and Soil Bulk Density As Affected by Cover Crop Species in a No-Tillage System
01/May/2015
Soil aggregation and the distribution of total organic carbon (TOC) may be affected by soil tillage and cover crops. The objective of this study was to determine the effects of crop rotation with cover crops on soil aggregation, TOC concentration in the soil aggregate fractions, and soil bulk density under a no-tillage system (NTS) and conventional tillage system (CTS, one plowing and two disking). This was a three-year study with cover crop/rice/cover crop/rice rotations in the Brazilian Cerrado. A randomized […]
EFFICIENCY OF THE DENSE SOLUTIONS IN PHYSICAL FRACTIONATION OF SOIL ORGANIC MATTER
01/Mar/2015
The mechanisms of stabilization of organic matter (OM) have been studied in Brazilian tropical and subtropical soils; however, few studies have evaluated the influence of the methodological part of the use of the solutions in the results. The aim of this study was to evaluate the efficiency of two salt solutions (1.8 kg dm-3 sodium iodide – NaI, and 2.0 kg dm-3 sodium polytungstate – SPT) in separation of densimetric soil organic matter (SOM) fractions in two soils (Acrisol from […]
ASPECTS OF THE SILVOPASTORAL SYSTEM CORRELATED WITH PROPERTIES OF A TYPIC QUARTZIPSAMMENT (ENTISOL) IN MATO GROSSO DO SUL, BRAZIL
01/Mar/2015
In Brazil, grazing mismanagement may lead to soil and pasture degradation. To impede this process, integrated cropping systems such as silvopasture have been an effective alternative, allied with precision agriculture based on soil mapping for site-specific management. In this study, we aimed to define the soil property that best sheds light on the variability of eucalyptus and forage yield. The experiment was conducted in the 2011/12 crop year in Ribas do Rio Pardo, Mato Grosso do Sul State, Brazil. We […]
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 […]