عنوان مقاله [English]
نویسنده [English]چکیده [English]
"Water Erosion Prediction Project model" is one of the most prominent process-based model with physics base that are able to predict soil loss and sedimentation by using spatial-temporal distributional mechanisms and processes on hillslopes and inside of stream. This model can be used in agricultural, rangeland, forest and road land uses. The WEPP model may be used in both hillslope and watershed applications and is able to estimate runoff, erosion and sediment yield as sequence year or during a storm.The model is a distributed parameter, continuous simulation and erosion prediction model. The distributed input parameters include rainfall amounts and intensity, soil textural qualities, plant growth parameters, residue decomposition parameters, effects of tillage implements on soil properties and residue amounts, slope shape, steepness and orientation and soil erodibility parameters. The major inputs to WEPP are a climate data file, a slope data file, a soil data file and a cropping/ management data file. If the user is simulating irrigation, additional input files are necessary. Applying WEPP in a watershed application also requires additional input file which provide information in channel and impoundment characteristics as well as watershed configuration. The WEPP model as applied to hillslopes can be subdivided into nine conceptual components: climate generation, winter processes, irrigation, hydrology, soils, plant growth, residue decomposition, hydraulics of overland flow and erosion.Erosion prediction is used wildly and as an effective tool in designing and programming for soil protection. For running the WEPP model, the climate information should be converted to acceptable format by WEPP model that this process is a hard work especially in regions with luck of data. This problem has caused that many users of WEPP model use the similar station in US to build climate file and then make to reduce model efficiency rate in areas outside of US. Then, in this study, it has been to produce the climate file of the WEPP model using meteorological data of Sanganeh watershed and BPCDG program. The final file is used in WEPP Model and then it make to reduce errors for estimating the climatic parameters. For this purpose, after collecting the required data, the entrance files of BPCDG program was provided in Not pad format and was introduced to the wepp model. The obtained result shows that WEPP model is able to identify the climate file and read it properly. Finally, this process causes to improve the accuracy of the model output.