Emergy-Based Urban Ecosystem Health Evaluation: Evidence from Suzhou, China

Given that the urban area is a complex ecosystem consisted of natural, societal and economic entities, urban ecosystem health evaluation is necessary for the scientific decision-making and proper ecological restoration. In this paper, the framework and methodology of urban ecosystem health evaluation based on emergy are proposed. The system of indices is developed including vigor, structure, resilience, ecosystem service function maintenance, and environmental impact. The paper take Suzhou urban ecosystem as an example, introduce the method of emergy-based evaluation, then evaluate the Suzhou ecosystem health during 2000 to 2007. The results show that Suzhou has obtained the better ecosystem vigor, structure, resilience and service function maintenance during 2000-2007, there also had a larger environmental pressure during its development. But the general trend of urban ecosystem has great development in recent years.