EVALUATION OF SOIL LOSS IN GUARAÍRA BASIN BY GIS AND REMOTE SENSING BASED MODEL <a href="http://dx.doi.org/10.4090/juee.2007.v1n2.044052" target="blank">(doi: 10.4090/juee.2007.v1n2.044052)</a>

Keywords: ungauged basin, sediment yield, hydrological model


Environmental degradation, and specifically erosion, is a serious and extensive problem in many areas in Brazil. Prediction of runoff and erosion in ungauged basins is one of the most challenging tasks anywhere and it is especially a very difficult one in developing countries where monitoring and continuous measurements of these quantities are carried out in very few basins either due to the costs involved or due to the lack of trained personnel. The erosion processes and land use in the Guaraíra River Experimental Basin, located in Paraíba state, Brazil, are evaluated using remote sensing and a runoff-erosion model. WEPP is a process-based continuous simulation erosion model that can be applied to hillslope profiles and small watersheds. WEPP erosion model have been compared in numerous studies to observed values for soil loss and sediment delivery from cropland plots, forest roads, irrigated lands and small watersheds. A number of different techniques for evaluating WEPP have been used, including one recently developed in which the ability of WEPP to accurately predict soil erosion can be compared to the accuracy of replicated plots to predict soil erosion. WEPP was calibrated with daily rainfall data from five rain gauges for the period of 2003 to 2005. The obtained results showed the susceptible areas to the erosion process within Guaraíra river basin, and that the mean sediment yield could be in the order of 3.0 ton/ha/year (in an area of 5.84 ha).