Urban Ecosystem Health Evaluation Based on Set Pair Analysis: A Case Study on Chongqing City

Set Pair Analysis (SPA) is a new methodology to describe and process the system uncertainty and has been applied in many areas recently. In view of the uncertainty and complexity in the process of urban ecosystem health evaluation, the paper introduced SPA theory and established an evaluation model. In the model, identity-discrepancy-contrary connection degree formula embodied certainties and uncertainties of the evaluation system. In addition, all indexes were summarized into five-dimensional connection numbers. As an example, the paper evaluated urban ecosystem health conditions of Chonqing city from 1997 to 2007 by the model. The results show that urban ecosystem health conditions of Chongqing improve steadily during the period but need to be improved. Urban ecosystem health evaluation model combines qualitative description with quantitative analysis and takes full advantage of uncertainty, so it provides a new way to evaluate urban ecosystem health.