Abstract:

Zhang Wei River Basin lies on the south of Hai River Basin, and it is one of the typical areas in north china that experiencing water shortage and water environment deterioration. Based on SWAT (Soil and Water Assessment Tool), Zhang Wei River Basin distributed hydrological model is established. Based on DEM(100m×100m) , considering location of hydrologic stations and four Large reservoirs, Zhang Wei River Basin was delineated into 74 sub basins and 940 Hydrological Response Unit (HRU). Topographic characteristics of each sub basin including slop and river networks are extracted automatically from DEM. The basic data including DEM, soil data, rainfall, weather data, land use and reservoir out flow data of Zhang Wei River Basin are collected and processed for the model. The soil and land use data are reclassified for the model and the soil physical properties database is created. The distributed hydro- process is simulated by using the hydro meteorological data from 2000 to 2004. SWAT model is calibrated with observed data from six principal hydrologic stations in Zhang Wei River Basin and the important parameters sensitivity is analyzed and the laws that changing some important parameters how to affect model results are discovered. The reliability of the SWAT model is validated by comparing the model outputs with Water Resource Reports. The mean relative error is less than 10%. The study results in this paper make a good demonstration for applying SWAT model in China, and lay a good foundation for establishment of whole Hai River basin distributed hydrological model.

Key words: parameter calibration, sensitivity analysis, SWAT model, Zhang Wei River Basin