Top-down versus bottom-up: Spatial pattern and human mobility of newly developing industrial towns in Chinese “city-NIT” network

Abstract

In recent decades, during Chinas rapid urbanization and industrial transformation, newly-developing industrial towns (NITs) have emerged at the interface between cities and rural areas in China. Among them, characteristic towns (Tese Xiaozhen) and Taobao towns exemplify top-down and bottom-up development pathways, respectively. These emerging towns may become critical nodes in China’s evolving urban–rural system and present opportunities for modeling human mobility. This study focuses on the spatial patterns, human mobility, and their network features of NITs within China’s urban system. Specifically, we analyzed the spatial distribution of NITs and their geographic linkages with major cities. Under hypothetical short-term mobility scenarios, interconnections within the “city–NIT” system were simulated using both the radiation model and the gravity model, followed by a comparative analysis of the two approaches. Furthermore, the radiation model outputs were used to construct a directed city–NIT network, which was subsequently evaluated using complex network indicators. Results indicated significant differences in spatial distribution between characteristic towns and Taobao towns, with the latter prominently concentrated in coastal areas. Despite differences in model assumptions, results from both models showed strong positive correlations across spatial scales, with radiation model estimates exhibiting greater regional stability. From a directed network perspective, NITs channeled short-term mobility flows, shaping sub-networks anchored by major metropolitan areas. This underscores the ongoing redefinition of China’s urban system, in which smaller nodes are capable of attracting or catalyzing short-term population movements. These findings suggest differences in adaptability between the two primary human mobility models. The findings may inform optimal planning for short-term human mobility to NITs and deepen understanding of the spatial organization and hierarchical characteristics of China’s urban system. Further, the proposed framework offers a reference for integrating emerging towns in other developing countries into existing urban systems.