Compressibilidade e suscetibilidade à compactação de um latossolo vermelho sob diferentes condições de preparo e manejos

Abstract

The soil is a natural resource slowly formed from the weathering of rocks and has a huge importance for humanity. Nevertheless, the farm may generate intense soil degradation by processes such as compaction. The soil compaction is an example of physical degradation occurs due to the application of external forces on the soil, resulting in a physical barrier to growth in depth of root crops, thereby limiting the uptake of water and nutrients. In order to prevent soil compaction occurs, an important indicator to be known is the soil load-bearing capacity, which is the maximum pressure that can be applied to the soil without further compaction occurs. The aim of this study is to determine the ability of a Rhodic Ferralsol Load Support in different moisture conditions and under different tillage systems and soil management and determine the influence of tillage systems on indicators of soil physical quality. For this, undisturbed soil samples conducted under different tillage systems / management were collected and subjected to physical testing and Uniaxial compression test in different soil moisture conditions. The systems will be tested: No-Tillage (PD); No-tillage with additional compaction (PDC); Minimum cultivation (ESC 2015) and soil chiseling every two years (ESC 2014). The soil bulk density in the surface layer was significantly higher in PDC (1.39 Mg / m³), and the lowest average were found in ESC 2015 (1.1 Mg / m³). In the layer 10-20 cm the highest averages were obtained respectively in treatments ESC 2014 (1.34 Mg / m³) and PDC (1.33 Mg / m³). Total porosity in the surface layer was higher in the tillage system with involving the movement of soil and subsurface layer the highest average was found in PD. The Load Capacity in each treatment was increased to the extent that the soil moisture was reduced. In the surface layer conducted under minimum tillage soil was more susceptible to compaction and less susceptible was the PDC. The load capacity proved to be an important tool to be used in conservation soil tillage to prevent compaction.