Runoff Simulation Based On SWAT Model In The Xixi Watershed Of The Jinjiang River

It is quite necessary to study the water budget in the Xixi watershed based on thedistributed hydrological model because of the impact on the water supply due to theaccelerated urbanization process.One such model available for the water resources professional is the Soil and WaterAssessment Tool(SWAT). Is is developed by the Agricultural Research Center of theUnited States Department of Agriculture. Through the conversion of soil texture andlanduse types, watershed subdivision and hydrological data collection, the efficientcreation of the input database required by the model simulation is set up.The model is calibrated with the measured runoff data of 1970—975, and theparameters of the study area are determined. The simulation results are obtained with theaccuracy of a R~2 of 0.92 and an E of 0.91. The model is further validated with themonthly flow of 1976—1979, which suggests excellent results. It shows that the SWATmodel is applicable in the southeast area of China.With the validated model, 4 landuse scenario models and 24 sets of temperature andprecipitation combinations are established to simulate the responses of the annualrunoff. The simulation results show that with the increase of vegetation coverage theannual runoff increases in the basin. The variation of runoff would be more sensitive inprecipitation than in temperature.