DETERMINATION OF THE EROSIVE SUSCEPTIBILITY FROM A HYDROGRAPHIC BASIN USING FREE AVAILABLE GEO-TECHNOLOGY

Abstract

Erosion is a natural process resulting from the interaction of rainfall and soil, which is enhanced by factors such as inadequate management of soil and removal of vegetation cover. This causes an excessive production of sediments, generating phenomena such as eutrophication and silting of watercourses. The Universal Soil Loss Equation (USLE), allows to estimate erosion under different land use/land conditions as well as under variable slope, slope length, soil types and rainfall. It allows the elaboration of thematic maps and it is an important research tool to analyze the erosive process. When applied with open and free available geo-technologies, it dramatically reduces the costs of performing the study. This study aimed to map and analyze qualitatively the erosive susceptibility of the Laranja Doce hydrographic basin, located in the city of Dourados / Mato Grosso do Sul State in the year of 2016, applying the USLE and geo-technologies that are available free on Internet. The average annual soil losses ranging 0-33 ton/ha/ year were obtained. Most of the area was classified with Low to Moderate Erosion since its erosive rate was lower than 15 ton/ha/year. It was observed that the spatial distribution of erosion is influenced especially by the soil cover and relief features described by the CP and LS factors, respectively