Regional consumption, material flows, and their driving forces: A case study of China's Beijing-Tianjin-Hebei (Jing-Jin-Ji) urban agglomeration

Continuous urbanization and a coordinated regional development strategy have gradually shaped urban agglomerations as new and massive centers of resource consumption in China. Therefore, understanding the material consumption status and the underlying mechanisms for typical Chinese urban agglomerations will support efforts to promote regional resource-utilization sustainability. In this study, we analyzed material consumption and its structure in the Beijing-Tianjin-Hebei (Jing-Jin-Ji) urban agglomeration from 2000 to 2015 and traced the sources of material consumption and underlying processes from a metabolic perspective. We also identified the main contributors and key drivers behind the changes of consumption during this period. The urban agglomeration's total consumption increased 2.2 times compared to the 2,000 level during the study period, with metallic minerals accounting for the largest proportion. Highly developed cities, including Beijing, Tianjin, Shijiazhuang, Tangshan, and Handan, consumed the largest amounts of materials and generated the most wastes. These cities also relied heavily on both internal and external resources and exchanged materials frequently among their metabolic compartments. Economic activity was the strongest contributor to the increased material consumption, followed by the population increase, whereas decreasing material-consumption intensity (increased efficiency) restrained the growth of material consumption somewhat. Our application of the material-flow accounting framework at the scale of an urban agglomeration provides support for future research on material consumption in other typical urban agglomerations, where it can provide support for policy development to alleviate regional resource shortages.