Abstract:

In order to know the condition of hydrology and water resources, forecast the physical hydrology process, use water resources reasonably and take effective measures on the soil erosion in the Maotiaohe watershed. Based on GIS, the author installed spatial database, climate database, land utilization database, and soil attribute database of the Maotiaohe watershed for the establishment of SWAT (Soil and Water Assessment Tool) to simulate the hydrological and sediment process in the watershed. Taking the particular hydrological characteristic of southwest karst region into consideration, the author successfully established the SWAT model of the Maotiaohe watershed on GIS platform by using the parameters selected from abovementioned databases. The runoff generation and sediment in the watershed each month of 2006 and 2007 were also simulated to indicate the dynamic of watershed runoff and soil erosion using the SWAT model. Furthermore, the adaptability of the SWAT used to simulate the karst watershed was assessed by comparing field observation data with simulation data of the watershed runoff and sediment. The results showed that the SWAT model could present a good simulation on the hydrological process and sediment of the Maotiaohe watershed, and generalized the parameters of the watershed, causing change of the simulation result. Finally, the soil erosion modulus was calculated in the 27 sub-basins delineated by the SWAT. The result also showed that serious soil erosion occurred mainly in the lower of Maotiaohe watershed, where more attention should be paid to and some practical measures should be taken to reduce soil loss.