城市生态系统承载机制定量研究——以长江三角洲为例

Quantitative study on loading relationship of urban eco-system: take Changjiang Delta as example

城市生态系统是自然 -社会 -经济复合生态系统 ,探讨其内部各要素的相互作用机制对于实施可持续发展战略、建设生态城市具有理论指导意义。本文尝试将自然生态系统承载力理论扩展到城市生态系统 ,以分析其内部诸要素间的相互作用机制 ,提出了城市生态系统承载机制的水桶模型。采用层次分析法构建了城市生态系统承载机制定量评估模型 ,并以长江三角洲具有代表性的八城市为操作对象进行了研究。案例结果表明 ,长三角八城市的综合承载指数排序由大到小依次为 :无锡、南京、杭州、上海、常州、宁波、苏州、扬州。

This paper aims to review and extend the theory of the loading capacity for the urban ecosystem. Based on the reviewing of the loading capacity of the urban areas, the authors advanced a concept of the loading relationship. Sociometric activity is the driving factor while ecological environment is passive; the interface relationship between them is the press and the loading relationship, which is known as the loading relationship of urban ecosystem. Urban ecosystem is by nature an economic-social-environmental complex system. It is of an urgent need to study the internal interaction among all the interactive factors to build a nice eco-city and prepare a sustainable development strategy. Next, the paper has made a systematic discussion of the watering bucket concept model to describe the carrying relationship of urban eco-system: the resource sustaining system and the environmental limit system, which is regard as the bottom and the wall of the bucket respectively. On the basis of the evaluation model suggested by the authors, 46 indicators have been set up to describe the relationship of urban system with the analytic hierarchy process (AHP) and a series of index, such as the system loading index (SCI), system limited index (SLI) and comprehensive loading index (CCI). According to the model, when the SCI is bigger than 1, it means that the resource consumption of the urban ecosystem would be unsustainable. But, when the SLI is smaller than 1, it would mean that the waste-loading ecosystem would be sustainable. And finally, eight representative cities of the Yangtze River delta were taken as a sample for study, with a quantitative evaluation done. The results indicate that: the system loading index (SCI) of Wuxi, Hangzhou, Nanjing and Shanghai is all bigger than 1; the system limited index (SLI) of Nanjing is bigger than 1 and the sequential order from the high to low can be shown as follows: Wuxi, Nanjing, Hangzhou, Shanghai, Changzhou, Ningbo, Suzhou, Yangzhou.