3290 results

Soil water retention and s index after crop rotation and chiseling

Juliano Carlos Calonego, Ciro Antonio Rosolem

01/Dec/2011

Soil compaction can be minimized either mechanically or biologically, using plant species with vigorous root systems. An experiment was carried out with soybean (Glycine max) in rotation with triticale (X Triticosecale) and sunflower (Helianthus annuus) in fall-winter associated with pearl millet (Pennisetum glaucum), grain sorghum (Sorghum bicolor) or sunn hemp (Crotalaria juncea) in spring. Crop rotation under no-till was compared with mechanical chiseling. The experiment was carried out in Botucatu, São Paulo State, Brazil. Soil quality was estimated using the […]

Soil erosion resistance in ravines in a sandy clay loam oxisol

Kalinny Patrícia Vaz Lafayette, José Ramon Barros Cantalice, Roberto Quental Coutinho

01/Dec/2011

Ravines represent one of the formations resulting from water erosion, with concentrated surface water flow down hillsides of degraded areas, yet without subsurface water flow. The objective of this study was to evaluate hydraulic flow conditions in ravines as well as to determine soil erosion resistance parameters: soil erodibility (Kr) and critical shear stress (τc) on the ravine surfaces, as well as to determine soil erodibility at several depths of degraded hillsides along the coastline of the state of Pernambuco. […]

Changes in chemical properties of a latosol by weed management in coffee plantions

Cezar Francisco Araujo-Junior, Paulo Tácito Gontijo Guimarães, Moacir de Souza Dias Junior, Elifas Nunes Alcântara, Aretusa Daniela Resende Mendes

01/Dec/2011

Weed control is one of the most intensive management practices in coffee plantations resulting in changes in soil chemical properties. The objectives of this study were: a) to assess the effects of weed management in a coffee plantation on the chemical properties of a Dystroferric Red Latosol (Oxisol) compared to soil under native forest; b) to verify the relationship between soil organic carbon content (COS) and the effective cation exchange capacity (effective CEC) and the cation exchange capacity at pH […]

Field capacity estimation based on retention curve and soil water flux density

Alexsandro dos Santos Brito, Paulo Leonel Libardi, Jaedson Cláudio Anunciato Mota, Sergio Oliveira Moraes

01/Dec/2011

Field capacity is a parameter of undeniable importance for an adequate irrigation management. From the reliable determination of soil water content and field capacity, crop yields cam be optimized, maximizing the plant water use efficiency and preventing groundwater contamination by leaching of fertilizers and agrochemicals. The objective of this study was to evaluate field capacity (a) from the calculation of soil water flux density during water redistribution in a classical experiment to determine this parameter and (b) from a given […]

Interril erosion from area under burned and green sugarcane harvested by hand and mechanically

Marcos Vinícios Garbiate, Antonio Carlos Tadeu Vitorino, Bruno Andrade Tomasini, Anderson Cristian Bergamin, Elói Panachuki

01/Dec/2011

Although a number of studies related to environmental issues address air pollution, the increased use of biotechnology and mechanical harvesting of sugar cane, less attention has been paid to the negative environmental impacts caused by laminar erosion. This study aimed to determine the levels of organic matter (OM) and nutrients (P, K, Ca and Mg) in sediment and runoff water from interrill erosion from different sugarcane harvest systems (green and burnt cane), on a loamy Dystrophic Red Latosol (Oxisol). The […]

Growth, nodulation and nitrogen fixation of cowpea in soils amended with composted tannery sludge

Joseany Andrade Santos, Luís Alfredo Pinheiro Leal Nunes, Wanderley José de Melo, Marcia Barreto do Vale Figueiredo, Rajeev Pratap Singh, Antônio Aécio Carvalho Bezerra, [...]

01/Dec/2011

Tannery wastes generation is increasing every year and a suitable method for tannery sludge management is necessary in order to decrease this environmental problem. The composting is recognized as a suitable method for sludge recycling.. The effect of tannery sludge compost (TSC) rates on growth, nodulation and N fixation of cowpea was investigated. Sandy and clayey soils were amended with TSC at rates of 0, 7.5, 15, 30, and 60 t ha-1. The shoot dry weight of cowpea plants 45 […]

Effects of erosion and deposition on particle size distribution of deposited farmland soils on the chinese loess plateau

Pei Zhao, Ming An Shao, Wail Omran, Abdel-monem Mohamed Amer

01/Dec/2011

Particle size distribution (PSD) in the soil profile is strongly related to erosion, deposition, and physical and chemical processes. Water cycling and plant growth are also affected by PSD. Material sedimented upstream of the dam constructions formed large areas of deposited farmland (DF) soils on the Chinese Loess Plateau (CLP), which has been the site of the most severe soil erosion in the world. Two DFs without tillage on the CLP were chosen to study the combined effect of erosion […]

Influence of crust formation under natural rain on physical attributes of soils with different textures

Selene Cristina de Pierri Castilho, Miguel Cooper, Carlos Eduardo Pinto Juhász

01/Dec/2011

One of the main negative anthropic effects on soil is the formation of crusts, resulting in soil degradation. This process of physical origin reduces soil water infiltration, causing increased runoff and consequently soil losses, water erosion and/or soil degradation. The study and monitoring of soil crusts is important for soil management and conservation, mainly in tropical regions where research is insufficient to explain how soil crusts are formed and how they evolve. The purpose of this study was to monitor […]

Changes in physical properties of a red oxisol and of soybean yield under no-tillage affected by chisel plow types

Vitor Cauduro Girardello, Telmo Jorge Carneiro Amado, Rodrigo da Silveira Nicoloso, Tiago de Andrade Neves Hörbe, Ademir de Oliveira Ferreira, Fabiano Mauricio Tabaldi, [...]

01/Dec/2011

Soil compaction at high intensity degrees is a hardly reversible process in the no-till system (NT), mainly in clayey soils. Generally, its occurrence in croplands is often irregular and restricted to areas with a previous history of pressures associated to intensive traffic of agricultural machineries. The purpose of this study was to investigate changes in soil physical properties of a red Oxisol with clayey texture (450 g kg-1) and soybean yield, caused by two site-specific chisels and conventional (random) chisel […]

Soil-water retention curve by the filter paper method

Juliana Fenner Ruas Lucas, Maria Hermínia Ferreira Tavares, Décio Lopes Cardoso, Fabio Augusto Meira Cássaro

01/Dec/2011

The most traditional method to determine the soil-water retention curve is based on the Richards’ pressure plate apparatus. For practical reasons, cheaper and faster alternatives to the Richards’ apparatus are needed. Therefore, this study evaluated the use of the filter paper method. Initially, an Oxisol was sampled and physically characterized. Undisturbed soil samples were prepared and tested in Richards’ chamber, at pressures of 0, 10, 30, 60, 100, 300, 500, 1,000 and 1,500 kPa. In the filter paper test, the […]

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