Atributos físicos de um Latossolo Vermelho-Amarelo distrófico sob diferentes usos do solo e floresta nativa

Abstract

The physical attributes of a soil are important for the sustainability of agricultural and forestry systems, making it necessary to monitor its quality. In recent years, the deterioration of soil quality has been a subject of paramount importance in soil science, as the removal of vegetation cover and the intensive use of mechanization in all cultivation operations can result in a decrease in soil quality productive capacity. In this sense, the aim of this work was to analyze the physical attributes of a dystrophic RedYellow Oxisol subjected to different land use alternatives and under native forest. Sample collection and field trials were made up of undisturbed and deformed samples from eucalyptus plantation (PE), cerrado (CE), integrated crop, livestock and forest (ILPF), conventional corn plantation (PCM), extensive pasture (PEX) and native forest (FN). Normal Proctor tests were carried out to evaluate the maximum density and optimum compaction moisture, soil resistance to penetration and basic infiltration velocity (VIB). The alternative uses CE and PEX were the ones that resulted in the highest soil densities; with the NF having the lowest density, due to the greater presence of organic matter in this environment, generating a decrease in the pressure load applied to the soil structure. The CE and PEX alternatives also presented the lowest Optimal Humidity (Uot) values, given their state of consolidation due to non-returning of the soil and trampling by animals, as well as the highest Compaction Degree (GC), indicating a greater structural alteration of the soil when compared to the FN. All systems showed values of Basic Infiltration Rate (VIB) lower than the NF, indicating that anthropic activity interfered in the soil structure.