Quantifying the emergy flow of an urban complex and the ecological services of a satellite town: a case study of Zengcheng, China

In recent years, the sustainability of many metropolitan areas has been degraded due to rapid economic development. Zengcheng, as a satellite city of Guangzhou, has been developed as a demonstration area for improving regional urban sustainability and expanding the overall ecological capacity of Gua...
Ausführliche Beschreibung

In recent years, the sustainability of many metropolitan areas has been degraded due to rapid economic development. Zengcheng, as a satellite city of Guangzhou, has been developed as a demonstration area for improving regional urban sustainability and expanding the overall ecological capacity of Guangzhou. In this paper, an integrated evaluation based on emergy synthesis theory was conducted to examine whether Zengcheng can fulfill its role in providing ecological services and improving regional sustainability. Based on emergy indices, we assessed the sustainability of the social, economic, and ecological subsystems of Zengcheng. The results showed that the total emergy used (U), the emergy used per person (Ucap) and the empower density (ED) of Zengcheng were all at a low level compared to a selection of developed cities. However, the Ucap and the ED were higher than the national average. The emergy investment ratio (EMR) of Zengcheng was lower than all the selected areas in this study, suggesting that the development of Zengcheng is mainly reliant on the consumption of local resources. The Emergy Sustainable Index (ESI) of Zengcheng is 0.72 which is lower than many highly developed areas. Furthermore, three categories of ecological services of Zengcheng were also evaluated based on emergy. The results show that the total emergy-dollar value of ecosystem services and the ecological services empower density (ESED) in Zengcheng were $6.17E+09 and 1.20E+13 sej/m2, respectively. This indicates that Zengcheng can provide substantial ecological services and increase the overall ecological capacity of the Guangzhou region. Ausführliche Beschreibung