Avaliação da compactação do solo sob tráfego de veículos na colheita da cana-de-açúcar utilizando o modelo SoilFlex

Abstract

Nowadays, heavy vehicle traffic occurs during sugarcane harvesting increasing the risk of soil compaction. Research in this field had deeply improve the knowledge of the compaction process but still there is a need in developing field management plans based on research to guarantee the sustainability of agricultural soils submitted to traffic. Focusing in understanding the soil compaction phenomenon in agricultural soils and, with the aim of preventing it from occurring, researchers developed pseudo-analytic models (O’Sullivan et al., 1999; Keller et al., 2007; Schjønning et al., 2008) based on the previous work of Boussinesq (1885), Fröhlich (1934) and Söhne (1953). Keller & Lamandé (2010) explain that importance of developing and using pseudo-analytical models is that they are simple to use and the inputs are easy to acquire by the user. These models are then important tools for the soil compaction analysis and prediction after on field traffic under different soil humidity, wheel loads, type of tires, contact area and inflation pressure. The objective of this study was to model possible canaries of soil conditions and vehicle traffic to evaluate soil compaction using the pseudo analytical model SoilFlex. The area of study corresponds to an area of 120 x 120 m whit an Argissolo Coesso soil. Undeformed soil samples were taken at 0-0.1; 0.1-0.2; 0.2-0.3 e 0.3-0.4 m to determine soil bulk density and from those results 5 bulk density canaries were constructed, each one simulated with 4 possible water contents. The vehicles used in the traffic simulations during harvest were a heavy duty Truck and a sugarcane Trailer hauled by a Tractor. It was determined from the analysis of soil bulk density variation and stresses transmitted to the soil after traffic,obtained with SoilFlex, that the heavy duty Truck and the hauled Tractor generate soil compaction beyond the 0.2 m of depth when the initial bulk density was 1.3:1.4 and 1.5 g cm⁻³. Cone index analysis showed that the area is a critical compaction level in the 0-0.2 cm layer.