Falhas de rebrota e qualidade física do solo ao longo das sucessivas colheitas de cana-de-açúcar

Abstract

Sugarcane cultivation is characterized by large extensions of planted areas, as well as by high traffic of agricultural machinery, mainly in harvesting operations. Currently, two types of sugarcane harvest are used: mechanized and semi-mechanized; at this stage, large agricultural vehicles are used, as well as soil mobilization, which are responsible for the increase in compaction, which results in a decrease in the physical quality of the soil and an increase in failures in the field. Thus, the objective of this study was to evaluate the impact of agricultural vehicle traffic through the physical quality of the soil and the evaluation of sprouting failures in mechanized and semi-mechanized harvesting of sugarcane over the time of cultivation. Two study areas located within an 18 ha field cultivated with sugarcane were selected. In the first area, mechanized harvests were carried out with raw cane, and, in the second, semi-mechanized harvests with burnt cane. The study periods were: after planting and after the first, second, third and fourth harvest. In all areas, undisturbed and deformed samples were collected for the analysis of soil density, organic carbon, soil porosity, macroporosity, microporosity, penetration resistance and available water. In addition, sprouting failures were analyzed from planting to the fourth harvest. The number of failures increased throughout the harvests, as well as the extension of each one of them, this occurred more sharply in the mechanized area. It was not possible to observe differences in soil physical indicators in relation to mechanized and semi-mechanized areas, indicating that traffic operations during these two harvesting systems similarly influence the physical properties of the soil. Soil physical indicators were negatively affected by successive sugarcane harvests over time.