Comparison of erosion and sediment simulation methods in SWAT and WetSpa models

There are a wide range of models that are being used in the field of soil loss and sediment yield and they have variety based on the complexity, the processes they can simulate and concept of the models. SWAT and WetSpa are tow hydrologic models and sediment and erosion simulator that their compatibility with GIS has raised their capability. SWAT is a continuous, semi physically based and semi distributed hydrologic model which HRU is its smallest work unit and all several hydrological processes are simulated for each one of it. WetSpa is a continuous, distributed, physically based hydrologic model that simulates hydrologic processes in pixel size of 1m2. This model uses some relations with physical concepts to simulate erosion and sediment, but in SWAT, this process is estimated with the Modified Universal Soil Loss Equation (MUSLE) model. DEM, land use and soil maps along with weather data are main input parameters of both models. In this study it is attempted to describe the methods for simulation of erosion and sediment in both models and compare their capabilities briefly.