Prediction of water erosion in a watershed located in southeastern Brazil

Abstract

Water erosion modeling is a fast and accurate way to estimate erosion potential in watersheds. Among the models, we have the Revised Universal Soil Loss Equation (RUSLE) which has a simple structure, low implementation cost and can be used with readily available information, contributing to the planning of soil conservation practices. In this context, the objective of the work was to apply RUSLE to estimate water erosion in the Córrego da Laje watershed affluent directly from the reservoir of the Furnas Hydroelectric Plant, located in the south of Minas Gerais, a region of southeastern Brazil. In this region, water erosion is a serious problem that has caused the silting up of the hydroelectric reservoir and the depreciation of water quality. Soil losses were calculated in Geographic Information System based on topographic, edaphoclimatic characteristics, soil cover, and management practices. The average soil loss of the watershed was 26.80 Mg ha-1 year-1 with the predominance of highintensity erosive rates (> 15 Mg ha-1 year-1). Considering the basin use classes, sediment generation was higher in pasture areas (35.87 Mg ha-1 year-1), and in areas under maize cultivation (32.05 Mg ha-1 year-1). As areas with severe erosion are distributed throughout the watershed, a comprehensive water erosion mitigation plan should be adopted to reduce the environmental damage of the process.