An emergy-based analysis of urban ecosystem health characteristics for Beijing city

As an embodied energetic equivalent for integrated ecological economic evaluation, emergy was used to assess and analyse the urban ecosystem health characteristics associated with energy and material flows. Emergy-based indicators were systematically established with respect to vigour, structure, resilience, ecosystem service maintenance and environmental impact as five fundamental aspects of ecosystem health assessment. At the same time, set pair analysis was also introduced to quantify the relativity and the uncertainty of the urban ecosystem health indicators. Finally, a tentative case study of Beijing 1986-2005 was also carried out using the proposed method to present a useful tool for the urban ecosystem assessment and management.