Spatial variability of mechanical resistance of soil to penetration in mechanized harvesting of corn for silage

Abstract

Because it is directly related to plant growth, soil mechanical resistance to penetration (RMSP) has been the physical attribute prioritized in studies that study soil compaction. The objective of this study was to verify if the traffic of machines during the harvest of corn for silage entails the need to prepare the soil for the next crop. The AMSY was evaluated in the layers of 0.0-0.10, 0.10-0.20 and 0.20-0.30 m by means of a penetrograph and the water content of the soil in the layers 0-0.15 and 0.15-0.30 m, following a sample mesh with 45 points spaced at 20 m, before and after the corn harvest for silage, georeferenced with GPS equipment. The results were submitted to descriptive statistical analysis, analysis of variance and geostatistics. To demonstrate the variability of the attributes, thematic maps were made. The analyzes showed low values ​​of RMSP, with mean values ​​of 2.17 MPa. The traffic of machines during the corn harvest caused an increase in the mechanical resistance of the soil to the penetration, but reached levels below that described as critical limit of root penetration, and there is no need for conventional preparation for implantation of the next crop.