Influência da carga dinâmica na compactação e alteração estrutural de um Latossolo Vermelho sob diferentes sistemas de manejo

Abstract

One of the main consequences of the inadequate handling of soil is the compaction of its structure which leads to a loss of its sustainability and reduction of productivity. The goal of this study is to analyse the structural changes and the compaction of a oxisol under no tillage (NT) and conventional till (CT) when under the stress of different loads. To determine this influence, experiments were conducted on a traffic simulator and on a shear force equipment to register the superficial settling and calculate the soil’s compactation degree. A totally randomised approach with a factorial 2X5 scheme with 4 repetitions adding up to a total of 40 experimental units was utilised. The subjects were constituted of 2 areas (NT and CT) and 5 loads (0,50,100,150 and 200kgf). The results demonstrated that the utilised variables were capable of displaying the changes in compactation and structure of the soil. The superficial settling showed a linear increase until the 200kg load and higher values for the NT load; the density showed quadratic behavior increasing up to the loads of 150kg (NT) and 100kg (CT); the voids index presented a reduction of the values up to the loads of 150kg (NT) and 100kg (CT), with the highest values related to NT; the compactation degree increased until 150kg NT and 100kg CT, displaying much bigger values for NT. The cohesive intercept showed a tendency to increase to loads up to 150kg, which corresponds to the highest values for the CT area. The friction angle values increased until 150 kg (NT) and 100kg (CT) loads, with much higher values for CT. The variables associated with a possible better soil structure were associate with the NT area.