Argila dispersa em água e grau de floculação em um Latossolo Vermelho sob diferentes sistemas de manejo e plantas de cobertura em pré-safra da cultura da soja

Abstract

With regard to the various soil management and preparation systems, we highlight conventional tillage, characterized by the use of soil preparation techniques and procedures, such as ploughing and harrowing, and no-till, which is related to minimal tillage with the aim of protecting the soil from erosive processes and is limited to the sowing furrow. The aim of this study was to assess the water-dispersed clay content and degree of flocculation of a red latosol under no-till and conventional cultivation, as well as cover crops in the pre-harvest period of the soybean crop. The study was carried out in an experimental area of the Federal University of Uberlândia, located in the municipality of Monte Carmelo-MG. The design used was a block design with four replications. The treatments consisted of a combination of two management systems (no-till and conventional cultivation) and a fallow or five winter crops, which were cultivated before the soybean crop, totaling 12 plots per experimental block. Soil samples were taken from the 0 to 0.1 m, 0.1 to 0.2 m and 0.2 to 0.3 m layers to determine water-dispersed clay and the degree of flocculation. Analysis of variance was carried out and the means were compared using Tukey's test at the 5% probability level. The lowest levels of water-dispersed clay and the highest degree of flocculation were observed in the soil under no-till farming. The highest levels of water-dispersed clay were observed in the 0.20 to 0.30 m depth layer. Soils under millet and turnip rape cultivation showed the lowest levels of water-dispersed clay, suggesting an improvement in soil quality.