基于客观赋权法的长江流域环境风险时空动态综合评价

Dynamic assessment of environmental risk for Yangtze River basin using objective weighting method

为评估长江流域各省域单元环境风险状况,构建以风险源危险性、受体敏感性和恢复力3类指标组成的环境风险综合评价指标体系.引入"纵横向-拉开档次"法和"时序加权平均算子"法等客观赋权法,对流域各省级单元2000—2011年的环境风险进行动态综合评价.结果如下:时间上,2000—2011年长江流域环境风险呈先期有所下降,而后不断升高的特点;空间上,上海、江苏、河南为高风险区,安徽、湖南、湖北和浙江为较高风险区,四川、广西、重庆、云南等西部省份属中风险区,西藏和青海为低风险区.通过对流域各省级行政区环境风险时空动态综合评价和聚类分析,为流域的环境风险管理提供理论依据.

An assessment index system is built and it is composed of the hazards of risk source and the sensitivity and resiliency of risk receptors. The dynamic assessment of environmental risk in the Yangtze River basin from 2000 to 2011 was evaluated by using the ＂ vertical-and-horizontal scatter degree＂ method and the ＂time ordered weighted averaging operator＂ method. The results are given in the following. 1 ） Temporally, the environmental risk of the study area decreased slightly in the initial stage of the study period, followed by an obvious increase consequently. 2）Spatially, great variations in risk value indicate that the Yangtze River basin can be divided into the high, relatively high, medium, and low risk regions with assistance of cluster analysis. The high risk zone includesShanghai, Jiangsu, and Henan; the relatively high risk zone includes Anhui, Hunan, Hubei, and Zhejiang; the provinces in the central area of the Yangtze River basin, such as Sichuan, Guangxi, Chongqing, Yunnan, and so on, are in the medium risk zone; and the Tibet and Qinghai occupy the low risk zone. The temporal and spatial patterns of environmental risk for the Yangtze River basin provides important scientific basis for the environmental risk management.