Employing remote sensing to analyze non-point source pollution problems in riparian buffer strips of guanting reservoir
官厅水库库滨带非点源污染控制效应的遥感分析

Agricultural non-point source pollution (NPSP) has became an important factor to water eutrophication .It has been widely proved that the establishments of ecological riparian buffer strips (RBs) can effectively prevent the NPSP. This paper demonstrates the integration of the field-experiment and the technology of remote sensing (RS) to analyze the environmental influence in watershed scale to RBs in Guangting reservoir. The SPOT5 data were collected to analyze the land cover characteristics in the study area. Quick Bird data were used to improve the precision of the informations interpreted from SPOT5 data. Results indicated that (1) the update land use of RBs was not appropriate considering the problem of NPSP to Guanting reservoir. The areas ratio of forest was underestimated, so were the cover ratio of forest and grass. (2) Considering the average annual NPSP load of N, P in Guanting reservoir watershed were 1881 and 1012 thousand tons respectively, the RBs could reduce the total N by about 11.6%, and the total P by about 0.4%.(3) The watershed management strategies of Guanting Reservoir should focus on the agriculture supervision and the management of riparian buffer strips.