城市生态系统承载理论探索与实证——以长江三角洲为例

THE CARRYING THEORY OF URBAN ECO-SYSTEM WITH A CASE STUDY IN CHANGJIANG DELTA

为深入地探讨城市生态系统内部各要素的相互作用关系,将自然生态系统承载力理论扩展到城市生态系统,提出城市生态系统的承载机制概念。分别从微观作用与宏观表现两个角度提出承载机制模型,即承载递阶模型与水桶模型,初步构建了承载理论框架。在承载理论指导下,采用层次结构模型建立了承载机制评价指标体系,提出承载机制定量评估模型,由此可计算出城市生态系统承载指数,该指数是研究资源支持系统、环境约束系统与社会经济活动三者协调性以及城市生态环境对社会经济活动供容能力的重要判据。最后对长三角具有代表性的8个城市进行了实证研究。结果表明:长三角8个^城市的综合承载指数排序依次为:上海、南京、无锡、宁波、杭州、苏州、常州、扬州。

Urban ecosystem is an economic-social-environmental comprehensive system. It is important to discuss the inner interaction within the system to perform sustainable development strategy. In this paper, the theory of carrying capacity is reviewed and extended to the urban ecosystem. From the view of carrying capacity, we advanced the concept of carrying relationship: sociometric activity is the driving factor, while ecological environment is passive; the interface relationship between them is the press are and carrying re- lationship which is named as carrying relationship of urban ecosystem. Then two concept models which are the carrying hierarchy and watering bucket model are used to describe the carrying relationship of urban eco-system. An evaluation model, involving 35 indicators, is set up and a series of indexes, such as re- source carrying index (RCI), environment limited index (ELI) and comprehensive carrying index (CCI) is introduced to describe the carrying relationship of urban ecosystem. At last, an evaluation on the eight representative cities in Changjiang delta is carried out from the view of carrying relationship, and the result indicated that the sequence of the comprehensive carrying index (CCI))from the high to low is Shanghai, Nanjing, Wuxi, Ningbo, Hangzhou, Suzhou, Changzhou, Yangzhou.