Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory of Regional Sustainable Development Modeling, Chinese Academy of Sciences, Beijing 100101, China.
Sci Total Environ. 2019 Apr 20;662:446-454. doi: 10.1016/j.scitotenv.2019.01.252. Epub 2019 Jan 23.
Cities have been posing threats to local environment due to intensive human activities. Disordered urban metabolism can lead to unhealthy urban system operation. Studying urban metabolism can identify the characteristics and structure of urban system operations, thereby promoting sustainable development. We construct an ecological network to model the energy/material flows among the sectors of urban system in Beijing, Shanghai, Tianjin, and Chongqing, which are the most representative cities of China. Ecological network analysis was introduced to survey the system's characteristic of structure and function. Results show that Shanghai's urban metabolic system has the highest synergism with a value of 5.04, followed by Beijing, Chongqing, and Tianjin. Different cities vary considerably in terms of the relationships among the sectors. In Beijing and Chongqing, there is mutualistic relationship between environment and primary industry. Transportation forms a mutualistic relationship with tertiary industry and other sectors Only in Chongqing. The good relationships between primary industry and construction are merely seen in Beijing and Shanghai. However, some relationships are similar in the four cities, for instance, all the relationships between primary industry and advanced industry, and between construction and advanced industry are competition; All the relationships between environment and transportation are mutualism. We further explored the network stability and found that the studied urban systems are all located in a stable status relatively. Our research could reveal the synergy of urban operation, and provide a theoretical basis for optimizing urban metabolic processes by regulating the flows and guidance for sustainable urban development.
由于人类活动的密集化，城市对当地环境构成了威胁。城市代谢的紊乱会导致城市系统运行不健康。研究城市代谢可以识别城市系统运行的特点和结构，从而促进可持续发展。我们构建了一个生态网络来模拟北京、上海、天津和重庆这四个最具代表性的中国城市的城市系统各部门之间的能量/物质流。生态网络分析被用来调查系统的结构和功能特征。结果表明，上海的城市代谢系统具有最高的协同值（5.04），其次是北京、重庆和天津。不同城市的部门之间的关系差异很大。在北京和重庆，环境与第一产业之间存在互利关系。交通与第三产业和其他部门之间形成互利关系，仅在重庆如此。第一产业与建筑业之间的良好关系仅在北京和上海可见。然而，在这四个城市中，一些关系是相似的，例如，第一产业和先进产业之间以及建筑业和先进产业之间的所有关系都是竞争关系；环境和交通之间的所有关系都是互利关系。我们进一步探讨了网络的稳定性，发现所研究的城市系统都处于相对稳定的状态。我们的研究可以揭示城市运行的协同作用，为通过调节流动和指导可持续城市发展来优化城市代谢过程提供理论基础。
