基于地理信息系统的区域水环境承载力评价

Evaluation of Regional Water Environmental Carrying Capacity Based on Geographic Information System

掌握区域水环境承载力(WECC)对可持续发展政策的制定具有重要意义。针对恩施州的水环境现状,综合选取社会-资源环境-经济系统下的15个评价指标,构建水环境承载力评价指标体系。结合地理信息系统(GIS)空间分析功能,采用离差平方和组合赋权法对各指标的主、客观权重进行综合赋权,在GIS中将各指标进行栅格化处理并进行赋权叠加,得到2017年恩施州水环境承载力的量化值和水环境承载状态的空间分布图。结果表明,恩施州整体水环境承载力属一般水平,水环境承载力为优、良、一般、较差和差5个等级的面积比例分别为1.23%,27.24%,42.62%,19.17%,9.74%;其中来凤、宣恩、鹤峰3县水环境承载力最高,建始、巴东、咸丰3县水环境承载力稍次,利川市和恩施市的水环境承载力最差。研究成果可为恩施州可持续发展政策的制定提供指导。

Regional water environmental carrying capacity(WECC)is of crucial significance for the formulation of sustainable development policy.In line with the current situation of water environment in Enshi Prefecture,15 indexes in regards to society,resource environment,and economy were selected to constitute an index system for evaluating WECC.In association with the spatial analysis function of geographic information system(GIS),the subjective and objective weights of each index were given using the sum of deviation square,and each index was rasterized and superimposed in GIS to obtain the quantitative value of WECC and the spatial distribution map of WECC of Enshi Prefecture in 2017.Results suggest that the overall WECC of Enshi Prefecture is at a moderate level.The area proportion with WECC of 5 grades(excellent,good,moderate,inferior,and very inferior)is 1.23%,27.24%,42.62%,19.17%,and 9.74%,respectively.The WECCs of Laifeng,Xuanen,and Hefeng counties are the highest,and those of Jianshi,Badong and Xianfeng are slightly lower,while the WECCs of Lichuan and Enshi are the most inferior.