论文标题
根据人口分布和互动来构建多层城市集群
Constructing multi-level urban clusters based on population distributions and interactions
论文作者
论文摘要
城市（或城市集群）不是一个孤立的空间单位，而是与社会经济紧密联系的地区组合。但是，到目前为止，我们缺乏通过这些社会经济联系来定义多层城市集群的一致和定量方法。在这里，使用中国的颗粒种群分布和流数据，我们提出了一种自下而上的聚合方法，以量化多个空间尺度的城市群集。我们在人口密度流图中揭示了六个“阶段”（即水平），每个图都对应于从大到小的城市群集的空间构型。此外，我们的结果表明，ZIPF的定律仅在第五级之后才出现，这证实了城市法律的空间依赖性。我们的方法不需要预定义的行政边界，并且可以在全球范围内有效地应用。
A city (or an urban cluster) is not an isolated spatial unit, but a combination of areas with closely linked socio-economic activities. However, so far, we lack a consistent and quantitative approach to define multi-level urban clusters through these socio-economic connections. Here, using granular population distribution and flow data from China, we propose a bottom-up aggregation approach to quantify urban clusters at multiple spatial scales. We reveal six 'phases' (i.e., levels) in the population density-flow diagram, each of which corresponds to a spatial configuration of urban clusters from large to small. Besides, our results show that Zipf's law appears only after the fifth level, confirming the spatially dependent nature of urban laws. Our approach does not need pre-defined administrative boundaries and can be applied effectively on a global scale.
