A reach distribution model of non-point source pollution in plain river network area

摘要

The land area in river network is divided into some foursquare cells with certain scale for the demand of precision, proceeding from the physical mechanism of the rainfall-runoff and runoff pollution, the non-point source pollution from cells are estimated using the export coefficient of different land use types. According to the terrain of plain river network area and the positions of land cells and river network's reaches, a principle is advanced which indicates that the non-point source pollution from a land cell should all get into its closest reach. A corresponding relationship between a single land cell and its pollution receiving reach can be obtained under the principle. In view of the above, a spatial distribution model of the rainfall-runoff and non-point source pollution in reaches of plain river network area is established. The method can provide a technological support for the further research on the dynamic effect on water quality which is caused by non-point source pollution.