基于SWAT模型的黑河上游径流模拟及其对气候变化的响应-自然地理学专业论文.docxVIP

Abstract The hydrological model is a tool for the rational allocation of water resources. It plays an important role during the hydrological regime and agricultural production. In recent years, hydrological models have been developed to the stage of a distributed hydrological model, which describe model parameters, the spatial variation of the model structure and spatial variability of underlying surface and soil moisture. It is an effective tool to study the hydrological cycle. The soil and water assessment tool(SWAT) as a representative of the distributed hydrological model has a wide range of applications of runoff simulation, changes in watershed surface conditions, climate change response simulation, pollute transport modeling and so on. There are increasingly serious water shortages because of human unreasonable use for a long time, leading to a crisis of water cycle. The climate of the northwest is dry and the land is poor and the vegetation is low, where there is an increasing runoff owing to precipitation increasing and glacial ablation, causing landslides, water and soil loss and other disaters. Therefore, in the trend of global warming, studying runoff variation of the northwest has implications ans significance on grasping the runoff varitation to revent disasters, especially in arid and semi arid areas. The Heihe River basin, located in the middle of Hexi Corridor, which is one of the three major rivers in Gansu Province and 130,000 square kilometers. In recent years, there is shrinking natural vegetation and serious deterioration of grasslands in the upper reaches of Heihe River basin especially. The excessive development of the middle reaches of water resources lead to environmental degradation of downstream ecosystems and exacerbating water supply and demand. This paper selects the upper reaches of the Heihe River basin as the study area and uses the distributed hydrological model of SWAT(Soil and Water Assessment Tool), which is developed by the Ag