CROP RESIDUE DECOMPOSITION AND NUTRIENT MINERALIZATION IN SOIL WITH DIFFERENT TEXTURES
01/Dec/2015
ABSTRACT The sustainability of conservation farming systems is closely linked to return of nutrients to the soil through decomposition of crop residues. The aim of this study was to evaluate decomposition of crop residues and nutrient mineralization in soils with different textures over a 175-day incubation period. The experimental design consisted of a 6 × 4 × 5 factorial arrangement – six treatments, composed of four crop residues (corn, brachiaria, common bean, and Stylosanthes) and two controls, both without residues, […]
NUTRIENT AVAILABILITY AND RECOVERY FROM CROP RESIDUES IN SOIL WITH DIFFERENT TEXTURES
01/Dec/2015
ABSTRACT Crop residues on the soil surface not only provide physical protection but may release significant amounts of nutrients to the soil through decomposition. However, the availability of these nutrients to plants has not been sufficiently studied. The aim of this study was to evaluate the total contents of organic C and N, pH, and the availability and recovery rate of P, K, Ca, Mg, and S from the biogeochemical cycling of different crop residues over time in built soils […]
NORMALIZED DIFFERENCE VEGETATION INDEX AND YIELD OF WHEAT CULTIVARS UNDER DIFFERENT APPLICATION RATES OF NITROGEN
01/Dec/2015
ABSTRACT The management of nitrogen fertilization in wheat has proven to be a limiting factor for grain yield in the southern region of Brazil, and new techniques like the normalized difference vegetation index (NDVI) can be useful for estimating crop yield potential and, consequently, for determining N fertilization requirements. The objective of this study was to evaluate the use of NDVI, obtained through active and passive sensors, as a tool for estimating the grain yield of wheat cultivars under different […]
Nitrogen Supply For Summer Crops Through Early Application In Ryegrass Grazed By Sheep
01/Sep/2015
ABSTRACT Greater nitrogen (N) cycling is sought through Integrated Crop-Livestock Systems (ICLS). The aim of this study was to evaluate the effect of early fertilization of nitrogen applied to ryegrass grazed by sheep on the nitrogen nutrition index (NNI) of summer crops in ICLS. This study was carried out in a long-term protocol managed in the winter under two stocking methods, continuous and rotational, and two grazing intensities, moderate and low, with four replications. In summer, the area was divided […]
Sustainability of Wood Productivity of Pinus Taeda Based on Nutrient Export and Stocks in the Biomass and in the Soil
01/Sep/2015
ABSTRACT The impact of intensive management practices on the sustainability of forest production depends on maintenance of soil fertility. The contribution of forest residues and nutrient cycling in this process is critical. A 16-year-old stand of Pinus taeda in a Cambissolo Húmico Alumínico léptico (Humic Endo-lithic Dystrudept) in the south of Brazil was studied. A total of 10 trees were sampled distributed in five diameter classes according to diameter at breast height. The biomass of the needles, twigs, bark, wood, […]
Carbon and Nitrogen Mineralization in Soil Combining Sewage Sludge and Straw
01/Sep/2015
ABSTRACT The combined incorporation of sewage sludge (SS) and oat straw (OS) to the soil can increase straw carbon mineralization and microbial nitrogen immobilization. This hypothesis was tested in two laboratory experiments, in which SS was incorporated in the soil with and without OS. One treatment in which only straw was incorporated and a control with only soil were also evaluated. The release of CO2 and mineral N in the soil after organic material incorporation was evaluated for 110 days. […]
Soil Nitrogen and Carbon Stocks, and Soil Bulk Density in Organic Fertilization Systems of Conilon Coffee
01/Sep/2015
ABSTRACT Production of Conilon coffee under organic management systems has increased in the State of Espirito Santo, Brazil. However, information is lacking in regard to the impact of these management practices on soil carbon and nitrogen stocks. The aim of this study was to evaluate the effect of organic fertilization on C and N stocks and soil bulk density (Bd) in a Conilon coffee agrosystem. A field experiment was carried out in Linhares, ES, in a randomized block design in […]
Leather Industry Waste as a Nitrogen Source for Wheat and Rice in Succession
01/Sep/2015
ABSTRACT The stabilization process necessary for leather tanning, in the leather industry, generates a great deal of collagenic solid waste, which is a likely pollutant. This solid waste has high nitrogen content, which suggests potential for agricultural use. To evaluate the feasibility of application of industrial leather waste as an N source for wheat and rice crops, a greenhouse experiment was conducted with five application rates of N from collagen (0, 225, 450, 675, and 900 mg kg-1) and three […]
Micronutrient Accumulation in Conilon Coffee Berries with Different Maturation Cycles
01/Sep/2015
ABSTRACT The number of days between anthesis and maturation of conilon coffee berries varies according to the genotype. Thus, it is believed that periods of greater nutrient demand for fruit formation also vary according to the genotype, directly influencing fertilizer management. The goal of this study was to establish accumulation curves for the micronutrients boron, copper, iron, manganese, and zinc in conilon coffee trees with different maturation cycles. The experiment was conducted in Nova Venécia, State of Espírito Santo, Brazil, […]
Liming in Agricultural Production Models with and Without the Adoption of Crop-Livestock Integration
01/Sep/2015
ABSTRACT Perennial forage crops used in crop-livestock integration (CLI) are able to accumulate large amounts of straw on the soil surface in no-tillage system (NTS). In addition, they can potentially produce large amounts of soluble organic compounds that help improving the efficiency of liming in the subsurface, which favors root growth, thus reducing the risks of loss in yield during dry spells and the harmful effects of “overliming”. The aim of this study was to test the effects of liming […]