Urban Ecosystem Health Assessment Based On The Analytic Hierarchy Process(AHP)-Entropy Weight Method And The Fuzzy Mathematic Method

The influence of human activities on the urban ecological system is increasingly significant. The ecological system is suffering serious stress and gradually deteriorated. An accurate and rapid ecosystem health assessment method is important in the urban development planning, but a complete and common urban ecosystem health evaluation system is not available. In the study, a database of the urban ecosystem health evaluating indicators was established and a differentiated urban ecosystem health assessment index system was constructed based on the analysis results of original data. With the Analytic Hierarchy Process (AHP)-entropy weight method and fuzzy mathematics theory, we developed a complete set evaluation method. Then we selected 4 representative cities in the Yangtze River Delta to carry out an empirical study. The main study results are summarized as follows:(1) In the paper, we collected the information on the urban ecosystem health evaluation system, and established a relatively complete urban ecosystem health evaluation index system. In addition, we carried out the specific screening of the urban ecosystem health city according to the factor analysis method, so that the urban ecosystem health evaluation system could be quickly established for each city.(2) With the Analytic Hierarchy Process (AHP)-entropy weight method and fuzzy mathematics method, we established the fast evaluation method of urban ecosystem health and corresponding computing platform to realize the rapid evaluation of urban ecosystem health. Through the research of 4 representative cities in the Yangtze River Delta Urban, we confirmed that the urban ecosystem health evaluation system could quickly and accurately determine a city’s urban ecosystem health status.(3) The evaluation results of four representative cities showed that the ecosystem health level in Shanghai was Level Ⅱ (healthy). The unfavorable indexes of urban ecosystem health for Shanghai included the index per capita, some environmental indicators, and the natural resource index. The ecosystem health level in Nanjing was Level II (healthy). The unfavorable index of urban ecosystem health for Nanjing included environmental satisfaction index, environmental quality, etc. The ecosystem health level in Hangzhou was Level Ⅱ (healthy). The main factor hindering the development of Hangzhou is the insufficient investment in environmental protection, green construction, and urban infrastructure construction. The ecosystem health level in Suzhou was Level Ⅱ (healthy). The overall ecosystem of Suzhou was the best, but it could be further improved in terms of per capita income and infrastructure investment. According to the comprehensive indexes, the ecosystem health levels in the 4 cities were decreased in the following order:Suzhou> Hangzhou> Nanjing> Shanghai.(4) In the study, we established the urban system health evaluation index system and the innovative evaluation method and obtained a complete and rapid index system for urban ecosystem health assessment. We carried out an empirical study with the 4 representative cities in Yangtze River delta and put forward some proposals based on results. Comparing the previously reported results, this article verified the reliability of the evaluation results of the urban ecosystem health assessment system.