Abstract:

This study takes Taoer River basin, a typical basin in semi-arid region of Northeast China, as study area, and simulates its hydrological process by the soil and water assessment tool (SWAT) model. Parameter sensitivity analysis is carried out on the upper sub-basin and middle-lower sub-basin to identify the sensitive parameters affecting stream flow. Results show spatial heterogeneity of several parameters’ sensitivities, and the reason is the difference of runoff generating mode caused by spatial heterogeneities of climate and underlying surface. Calibration and verification of hydrological model are carried out by daily hydrological and meteorological data from 1988 to 1997, and the results show that average Nash-Sutcliffe efficiency coefficient (EC) of monthly runoff simulation at main stream gauging stations is 0.78 for calibration period and 0.72 for verification period, relative coefficient is more than 0.86, relative error of water budget is within 20%, and daily runoff simulation is also fairly good; while the simulation is not satisfied for dry period due to the inadequacy of precipitation gauging station to capture spatial and temporal distribution of precipitation. These researches show the applicability of SWAT model in modeling runoff generation and relative hydrological process in semi-arid region in Northeast China with scarce-data, and meanwhile it provides foundation and tool for improving further study in water resources integrated management of Taoer River basin.

Key words: SWAT model, sensitivity analysis, hydrological modeling, Taoer River basin