官厅水库库滨带非点源污染控制效应的遥感分析

Employing remote sensing to analyze non-point source pollution problems in riparian buffer strips of guanting reservoir

选取官厅水库库滨带为研究区域,应用SPOT5遥感数据对其结构进行了解析,建立了高分辨率的QuickBird遥感数据与SPOT数据的尺度转化关系,对SPOT信息提取结果进行了校核,以提高SPOT卫星对库滨带结构的解译精度;最后结合点上的实验结果对流域尺度上的库滨带的环境效益进行了分析.研究结果表明(1)官厅水库陆相库滨带的结构不利于非点源污染的防治,应该适当增加林地的比例,同时提高林地、草地的植被覆盖度;(2)按照官厅水库流域非点源区年均TN量为188.1×104t、TP量为101.2×104t计算,库岸库滨带对TN、TP的去除率分别为11.6%和0.4%;(3)为了有效地防止官厅水库流域的非点源污染,必须加强水库流域的农业管理和库岸库滨带的科学建设与管理.

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 coUected 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 agricuhurc supervision and the management of riparian buffer strips.