基于生命力指数与集对分析的城市生态系统健康评价

鉴于城市生态系统的生命特征,引入城市生命体概念,构建包括生产力、生活态、生态势和生机度的城市生命力指数,分别针对经济子系统、社会子系统、自然子系统及生态调控子系统来综合反映城市生态系统健康状况.引入集对分析这种不确定理论与方法,在充分考虑城市生态系统健康不确定性与相对性的基础上,构造各被评价城市与最优评价集的相对贴近度,开展城市生态系统相对健康状况比较研究,以促进城市生态系统健康水平的整体提升.利用基于集对分析的城市生命力指数综合评价模型及信急熵权重,比较了北京、上海、武汉、广州等16个城市2005年的生命力指数相对状况,结果表明:2005年,厦门、上海、北京、青岛等城市的生命力指数处于被评价城市中相对较高等级,即城市生态系统健康状况较优;而重庆、西安、银川、哈尔滨、成都等城市处于相对较低等级,即城市生态系统健康状况较劣.

Urban Ecosystem Health Assessment Based on Vitality Index and Set Pair Analysis

In light of characteristics of the urban ecosystem, the concept of urban vital organism is introduced to vividly and systematically assess the status of urban ecosystem from the macroscopical layer. Covering producing power, living status, ecological ascendancy and vital force, the urban vitality index is constructed to represent the urban ecosystem health states from the economic subsystem, social subsystem,natural subsystem and ecological regulatory subsystem, respectively. Set pair analysis (SPA), an uncertainty assessment method which systematically estimates the uncertainty of urban system, is also introduced to assess the urban ecosystem health. Through SPA, multiple indicators of urban vitality index can be integrated to evaluate the relative approximate degree of real index set to the optimal one, which can be used to describe the relative health states of the urban ecosystems and finally impel the improvement of the whole urban ecosystem health status.With the integrated SPA-based urban vitality assessment model and the indicator weights determined by information entropy method, the relative status of urban vitality index in 2005 among each urban ecosystem is measured, by choosing sixteen typical cities including Beijing, Shanghai,Wuhan, Guangzhou, etc. as study objects. The results show thai the health status of urban ecosystem based on urban vitality index of Xiamen,Shanghai, Beijing, and Qingdao is relatively good, while the states of Chongqing, Xi'an, Yinchuan, Harbin and Chengdu is relatively bad.