Identification of Metropolitan Area Boundaries Based on Comprehensive Spatial Linkages of Cities: A Case Study of the Beijing–Tianjin–Hebei Region

Abstract

As a regional management unit to solve "urban diseases,” metropolitan areas are gradually attracting widespread attention. How to objectively and accurately delineate the boundaries of a metropolitan area is the primary prerequisite for carrying out targeted studies and precisely formulating regional planning measures. However, the existing methods for delineating metropolitan area boundaries have problems, such as high data acquisition costs, subjectivity, and a single perspective of urban linkage. To address the above problems, we propose a “bottom-up” approach to metropolitan area boundary delineation based on urban comprehensive spatial linkages. We used only publicly available data to construct a directionally weighted network of urban spatial linkages, and applied community detection algorithms to delineate metropolitan area boundaries. Taking the Beijing–Tianjin–Hebei region as a case study area, the method’s validity was confirmed. The results showed the following: (1) Eight metropolitan areas were delineated within the region, with two types of metropolitan areas: “Inter-municipal” and “single-city”. (2) The overall accuracy of the delineation results reached 83.41%, which is highly consistent with their corresponding isochrone maps. (3) Most metropolitan areas were observed to have an obvious “central–peripheral” structure, with only the JingJinLang metropolitan area being a polycentric mature metropolitan area, whereas the other metropolitan areas remained in the initial stage of development, with Zhangjiakou and Chengde not yet having formed metropolitan areas. This study’s methodology highlights the basic criteria of “inter-city spatial linkage” as the foundation for boundary delineation, avoiding the inaccuracy caused by the subjective selection of boundary thresholds, and can also accurately determine the developmental stage and internal spatial structure of metropolitan areas. Our method can provide new perspectives for regional boundary delineation and spatial planning policy formulation.

Identification of Urban Clusters Based on Multisource Data—An Example of Three Major Urban Agglomerations in China

“…Initially, research on urban agglomerations defined physical territories based on size and density; however, related studies have since shifted towards defining functional territories based on the degree of city connection. Consequently, there has been a growing focus on flow space and linkage networks in urban research [35].…”

The Impact of Coordinated Development Policy on the Spatiotemporal Changes of Industrial Structure of Beijing–Tianjin–Hebei Urban Agglomeration

“…As the essential content and key support for the coordinated development of BTH, industrial integration is conducive to giving full play to the comparative advantages of various regions, guiding the orderly transfer and undertaking of industries, and gradually forming a rational spatial layout, as well as a scientific industrial chain of urban agglomeration. As the largest economic agglomeration in the north, the Beijing-Tianjin-Hebei region has achieved preliminary successes in terms of coordinated development, but the overall level is still lacking [5]. At present, these issues are the focus of attention in solving Beijing's "big city disease" and are also the top priority in the realization of BTH's coordination: What is the progress of non-capital function dissolution?…”