Fuzzy Synthetic Evaluation on Urban Ecosystem Health

Ecosystem health is the prerequisite for ecosystem service function. To assure socio-economic sustainable development, how to effectively evaluate the trends of urban ecosystem health is a key issue for ecological planning. The paper established an evaluation model of urban ecosystem health based on the approaches of entropy weight and fuzzy logic mathematics, which avoided the uncertainty in estimating the standard of urban ecosystem health subjectively. Wuhan urban ecosystem was selected as an example for application and its health conditions from 1993 to 2004 was assessed. The results showed that: (1) The relative health status of Wuhan urban ecosystem health increased from 1993 to 2004. The most healthy year was 2003, and the least healthy year was 1994. (2) Based on the maximum membership degree principle, the maximum membership degree in human health group was 0.7627 (2003), in ecosystem service function group was 1.000 (2004), in social group was 1.000 (2001), in economic group was 0.9561 (2004), in environmental group was 0.7526 (1998).