Estimates of Erosion Sediment of Gavi River Catchment Using Mpsiac Method in GIS Environment

Gavi river catchment is located in the south west of Ilam city covering the area of 460 km² where different types of erosion incidences are noticeable therefore, estimating the amount of erosion and deposition is essential for soil and water conservation projects. The method of this study is based on litrature review, field and empirical models of erosion and sedimentation estimation. Empirical model of MPSIAC whit considers the most effective parameters in erosion and sediment is used as a chosen technique and the environmental parameters are analyzed in this format. At the end the results were compared to Bajk strait sediment station. GIS software is used to prepare the information layers. The results show that MPSIAC model is a good model in this area, because as a sample, the estimated amount of sediment in the area using MPSIAC model was 20.453 tons per square kilometer of sediment per year and estimated sediment in hydrometeric station of Bajak strait is 23.460 tons per year. It was also observed that the estimated sediment in this basin is in erosional Class4 and in terms of quality classification, erosion is in high level and according to the definition of this level it can be said that in this basin the relocation of the soil particles (dust) is in a rate that accomplishment of soil and water conservation programs should be in priority and lands usage should be limited.