Abstract:  

As a scientific basis for distinguishing urban and rural areas and demarcating the boundary of urban growth, the demarcation of the urban-rural space and dynamic evolution of urban-rural boundaries has always been one of the important aspects of geography research. Based on the data of land use, added value of secondary and tertiary industries, and population density of Nanjing from 1985 to 2016, this paper employs morphological and functional indicators, measured respectively by landscape disorder and construction land proportion as well as Population density and industrial added value, to identify the urban-rural space boundary. By dividing the indicators into kilometer grids, this paper applies “distance attenuation” and "breaking point" method to examine the evolution of the urban-rural space boundary. The results show that: (1) The urban-rural space boundary of Nanjing exhibits distinct expansion within 2000-2016, while the first stage (1985 to 2000) is characterized by infilling expansion and the second stage (2000 to 2016) is mainly dominated by spread expansion, the change rate in the second stage is significantly higher than that of the first stage. (2) The space boundary of urban-rural in Nanjing show different characteristics of expansion and most closely related to the development model at different stages, it’s change slowly in the urban state-owned economy and rural industrialization stage, and change rapidly in the rapid urbanization and open economy stage. (3) As a megacity, Nanjing has a high level of development in urbanization and urban-rural integration, and it is universal to use this area as an example to test the evolutionary identification method of urban-rural space boundary, and that can be applied to the identification of urban-rural space boundary in the rapidly developing metropolitan areas.