从城市到城市群：京津冀物质代谢特征及影响因素

随着城市化进程和一体化战略的持续推进，城市管理者急需了解城市规律以消减生态-资源-环境挑战，并提供坚实物质基础。以京津冀城市群及其组成城市为研究对象，创新性地从城市群和城市两尺度核算并分析了2000—2017年物质消耗状况及变化趋势，识别并对比了主要贡献物质、贡献部门和影响因素。研究表明：(1)研究期间，京津冀城市群物质消耗量总体上升。从物质类型看，主要由非金属矿物(>34.2%)拉动；从产业结构看，受到工业部门(>58%)绝对影响。首要驱动因素为经济规模(>50%)。(2)各城市物质消耗量与城市群较为类似，总体也呈增长态势，几乎均受到非金属矿物和工业部门驱动，且经济规模起到正向促进作用，不同的是物质消耗强度作用类型多样，且产业结构效应在城市中贡献更为突出。研究结果在一定程度上明确了城市及城市群代谢的规律，能够为优化资源利用效率和资源配置结构奠定基础，为城市及城市群生态管理与调控提供切实可行的落力点。

From cities to agglomeration: characteristics and driving factors of material metabolism in the Beijing-Tianjin-Hebei Region

With continuous urbanization and the integration strategy, the managers urgently need to meet the ecological-resource-environmental challenges, so as to provide strong material support for eco-social development. This study took the Beijing-Tianjin-Hebei region and its cities as example, calculated and analyzed the material consumption status and change trends of the two scales from 2000 to 2017, futhermore identified and compared the main material types, sectors and important drivers. The results showed that during the study period, the material consumption of the Beijing-Tianjin-Hebei region increased overall, mainly came from non-metallic minerals (over 34.2%) from perspective of material types and manufacturing sector (more than 58%) from the perspective of sectors, and economy size effect was the primary driver (over 50%). The cities, overall, showed similar trends as the region. The material consumptions increased in general, nearly all cities'' material consumptions were pulled up by non-metallic materials and manufacturing sector, while economy size presented positive effects. Differently, the consumption intensity effect had more significant inhibitory effect on the consumption growth of the region than each city, and the industrial structure effects on the urban scale were more prominent than the others. The results clarify the metabolism status of the Beijing-Tianjin-Hebei region and its cities to a cer tain extent, which can lay a foundation for optimizing resource efficiency utilization and reallocation, and can provide a practical and feasible impact for the ecological management and regulation in the region.