Abstract: With the increasing prominence of urbanization and urban environmental issues, urban ecosystem health assessment has become a hot topic in ecology. In this paper, four elements including vigor, organizational structure, resilience, and function maintenance were collected to construct an emergy indicator, the improved emergy urban ecosystem health index (IEUEHI), to assess urban ecosystem health. This index was used for assessing the ecosystem health of Hefei City, and compared with other six cities in China, i.e., Tianjin, Wuhu, Shanghai, Ningbo, Baotou, and Fuzhou. The results showed that the health level of Hefei decreased continuously from 2004 to 2008. The IEUEHI of the City was higher than that of Shanghai, Ningbo, Baotou, and Tianjin, but lower than that of Fuzhou and Wuhu. Therefore, it would be necessary to improve the health level of Hefei by decreasing the environmental threat and improving the city’s organizational structure and resilience and services.

Key words: East China Sea, Red tide, Remote sensing