Análise dos processos de erosão hídrica e produção de sedimentos na microbacia do Arroio Morungava, Gravataí-RS.

Abstract

Use planning and land use in basins can serve as a preventive tool to erosion. It is the object of this study, detailing the phenomenon of erosion and sediment yield in the micro basin of Morungava, Gravataí, RS. This study evaluated the erosion indicators described herein as organic matter and Clay soils and Hydromorphic soils, characterized in this study as profile types to perform the pedological characterization. The quantitative analysis was obtained by collecting the soil surface horizon, which was accomplished with the application of the volumetric ring method is spatially and analysis resulting from the use of Equation Universal Soil Loss (USLE) and the use of techniques of Geographical Information System (GIS). The assessment of sediment yield, and the distance and the fraction of that reaches the surface drainage network was obtained by applying empirical equations of Sediment Production Rate (SPR). The results show that the erosion indicators correlate, suggesting that the clay exerts a protective effect, reducing oxidation and loss of organic matter. The erosion of the watershed is approximately 52,000 t.year-1, out of which 15,452 t.year-1 results in the Production of Sediment (PS). The estimated distance indicative of the catchment area of these sediments by the annual water supply is 42 m.