Determining carbon metabolism in urban areas though network environ theory

Abstract

Carbon fluxes scenario within urban areas plays an important role in the global carbon cycle, which is critical for the adjustment of urban development activities influencing our living environment. Adapting network environ theory, a generic metabolic model is developed in this study for carbon metabolism in urban areas, in which compartmental utility analysis and system performance assessment are featured. Taking carbon dynamic of Hong Kong as a case study, the metabolic flows within urban carbon balance are illustrated though two analogous input/output networks. Based on this, the compartmental mutual relationships between different urban sectors are addressed and the overall properties of the city's carbon metabolism are aggregately evaluated. Our findings showed that each metabolic component has its specific mutual relations with other components connected, playing a unique role within the ecological system. As to Hong Kong's case, specifically, the metabolic system is considered self-mutual and stable when incorporating its interactions with its supporting environment. In light of these insights, potential extensions and applications of the network-based metabolic model in future are discussed. The recommendation is that the tracking of interactive relationships and pathways from network environ perspective be incorporated into present urban metabolism study for a more comprehensive sustainable urban design.