Forecasting Sediment with Erosion Potential Method with Emphasis on Land Use Changes at Basin

Experimental methods have been developed during the past decades for studying the effects of changes in land use on soil erosion. These involve the measurement of sediment yield at the basin. Each method has its advantages and limitations for a particular application at different scale soil loss estimates using different techniques commonly vary by an order of magnitude by various EPM (erosion potential method) models, thus to chose a proper method for erosion measurement is very important for all erosion studies. A grid-based distributed model EPM model compatible with ArcView Geographic Information Systems (GIS), was applied to the 344.91 km2 Upper Sezar River in DEZ basin. Model parameters were derived from a digital elevation model (DEM), land use and soil type map of the basin. These parameters and the observed daily meteorological data (1968-2006) were used (1) to test the performance of the EPM model to a large tropical basin for determined total sediment yield, (2) to identify the different erosion components. The use of yearly observations instead of monthly observations and the lack of other measurements of the hydrological processes.The deviations between the observed and simulated sediments may also be caused by the lack of a good representation of the meteorological conditions in the study area. The EPM model also provided insight into the main flow processes during the year