Modelling the impact of land-use changes on nonpoint source pollution loading

摘要

Land-use change, dominated by an increase in impervious areas, has a significant impact on water resources and particularly on nonpoint source pollution loading. In order to provide easy to use quick water quality assessment of the impact of land-use changes, a screening level GIS-based nonpoint source pollution loading model has been constructed using the curve number and event mean concentration methods The model is linked to a G1S for convenient generation and management of model input and output data, and advanced visualization of model results. The model was applied to the Guanlan River basin in the Pearl River Delta, Historical land-use scenarios for 1991, 1994 and 1998 were analysed to track land-use change in the watershed and to assess impacts on annual average runoff and NPS pollution.