Author(s): Qian Hong; Liang Xu; Zongliang Sun; Tian Tian; Ruimin Liu; Zhenyao Shen
Linked Author(s):
Keywords: Non-point source pollution; Three Gorges Reservoir Area; Small-scale watershed extended method
Abstract: Non-point source pollution has been increasingly recognized as a major contributor to the declining quality of aquatic environment in recent years. The non-point source estimation in large scale watershed is always difficult in most developing countries because of the data shortage. In this study, small-scale watershed extended method (SWEM) is introduced with a case study for large scale watershed. SWEM is the method which uses SWAT or other physical-based models in some small typical catchments in a large watershed, and then the simulating results of these small catchments are extended to the surrounding area until the NPS load in the whole watershed can be obtained. The selected small catchments should have sufficient data. The Three Gorges Reservoir Area, greatly affected by the Three Gorges Project, is a rapidly developing area with serious non-point source pollution problems. In this study, more than one fourth part of the reservoir region, approximately 15000km 2, is chosen as the research area for case study. In the selected region, Xiaojiang River is screened as a typical catchment to be simulated with SWAT model through accurate parameter calibration and validation. For the similar topographic and geographic factors, the parameter group is extended to other adjacent catchments and NPS pollution loadings are computed. The SWEM provided a practical approach for non-point source pollution loading estimation in large scale watershed.
Year: 2010