Examining the Evolution of China’s Urban Interlocking Networks Based on the Spatial Agglomeration of Producer Services

Agglomeration of producer services forms the basis for regional industrial layout optimization, whereas urban association adequately describes the spatial pattern of producer services agglomeration. Based on the relationship between the agglomeration of businesses around strongly related industries, this study constructs a multilayer network model to investigate the urban interlocking of agglomerated producer services in China. By analyzing urban hierarchy, configuration, directionality, clustering, and intermediation, we identify key cities, an urban agglomeration, and the characteristics and evolution of urban association patterns under industrial agglomeration. From 2005 to 2015, cities with agglomerated producer service economies expanded from central and eastern regions into the surrounding areas. We identify core producer services cities and major urban agglomerations in a region and define the radial configuration that forms around core cities. This reveals the weak agglomeration characteristics of surrounding areas and the national distribution of resources. Simultaneously, major urban agglomerations have factors that circulate between regions and are integrated into the overall interlocking network. Our results offer guidance for industrial layouts and further industrial development.