基于RS和GIS的珠江三角洲生态环境脆弱性综合评价

Integrated assessment of eco-environmental vulnerability in Pearl River Delta based on RS and GIS.

使用空间主成分分析法构建评价指标体系,采用层次分析法确定指标权重,结合遥感数据和地理信息系统软件,对珠江三角洲2004—2008年生态环境脆弱性进行了综合评价并对脆弱性成因进行分析.结果表明:生态环境极度和重度脆弱区主要分布在珠江三角洲中部,占整个研究区面积的34.0%;生态环境中度脆弱区主要分布在珠江三角洲东部,占25.5%;生态环境轻度和微度脆弱区主要分布在珠江三角洲西部,分别占28.7%和11.8%.中度和轻度脆弱区占整个研究区面积的54.2%,表明珠江三角洲大部分区域的生态环境属中度和轻度脆弱.影响珠江三角洲生态环境脆弱性的自然因素主要有海拔高度、大暴雨日数、水土流失比率、易涝耕地面积比率、归一化植被指数、景观多样性指数,人为因素主要有人口密度、单位面积废水排放量、单位面积废气排放量、土地利用变化、化肥施用强度、农药使用强度、万人机动车拥有量、环保投资指数.极度和重度脆弱区的主要特征是海拔低、洪涝灾害发生频率高、易涝耕地面积多、植被破坏严重、污染强度大和环保投资指数小等.

Based on the remote sensing data and with the help of geographic information system,an integrated assessment was conducted on the eco-environmental vulnerability of Pearl River Delta in 2004-2008.Spatial principal component analysis was used to generate the evaluation indicators,and analytic hierarchy process（AHP） was applied to determine the weights of the evaluation factors.The reasons causing the vulnerability of the eco-environment in Pearl River Delta were discussed.In the study area,its middle part was the most vulnerable region,occupying 34.0% of the total,eastern part was the moderately vulnerable region,accounting for 25.5%,and western part was the lightly and slightly vulnerable areas,accounting for 28.7 and 11.8%,respectively.Totally,the moderately and lightly vulnerable areas occupied 54.2%,indicating that a majority of the Delta was under moderate and light vulnerability.The natural factors affecting the eco-environmental vulnerability of the Delta were altitude,heavy rain days,water and soil erosion rate,flooded infield rate,normalized difference vegetation index（NDVI） and landscape diversity index,whereas the human factors were population density,waste discharge per unit area,exhaust emission per unit area,land use change,chemical fertilization intensity,pesticide application intensity,amount of motor vehicles possessed by ten thousands people,and index of environmental protection investment.The main characteristics of the extremely and heavily vulnerable regions were low altitude,high frequency of flood disaster,large flooded infield,serious vegetation degradation,high pollution level and low environment protection investment index.