Differentiation of urban-rural interface and its driving mechanism: A case study of Nanjing, China

The urbanrural interface is the frontier of urban expansion and rural development. Understanding the differentiation and driving mechanism of the urbanrural interface could help policy-makers mitigate negative impacts of development and promote integration through proper planning. Taking Nanjing as an example, this study provides new insights into the different types of urbanrural interfaces and what drives their. differentiation. We first built a conceptual framework to hypothesize how the urbanrural interface was differentiated. Based on multiple datasets, a two-step classification method (random forest model and k-medoids) and the multinomial logistic regression (MLR) model were then introduced to identify different urbanrural interfaces and explore influencing factors, respectively. The results show that 341 communities/villages were identified as belonging to the urbanrural interface, with 37 communities/villages as urban-dominant, 128 communities/villages as intertwined, and 176 communities/villages as rural-dominant. Most mean values of land use, demographic, and socioeconomic characteristics decreased sequentially from urbandominant to intertwined and rural-dominant interfaces. MLR results indicated that transportation and economy were common drivers, while policy orientation, planning, and location accounted for the different urbanrural interfaces. In combination with the conceptual framework and additional investigations, this study concluded the driving mechanism of urban-rural interface differentiation in Nanjing. Specifically, the development of urban-dominant interface was mainly promoted by local governments; the development of intertwined interface was usually driven by complicated factors with the involvement of many stakeholders; policies facilitated by central/regional government accounted more for the development of rural-dominant interface. With the above analysis, this study further discussed the relationship between the urbanrural interface and planning system, and proposed differential development and management suggestions for the urban-rural interface.