Research on identifying the geographical scope of urban physical area

The geographical scope of urban physical area is the basis for distinguishing urban and rural areas, establishing urban-rural statistics, formulating urban-rural policies, and implementing national spatial planning. It clarifies the scope for conducting research on cities, and contributes to control the scale of urban development, intensively utilize land, and accurately obtain urban population. This paper defines city in terms of morphological and functional dimensions, and constructs a conceptual model of the geographical scope of urban physical area. Based on the national population census data and historical population data, the national land survey data, the geographic monitoring data, map POI and other geographic spatial big data, it designs the overall technical framework for identifying the geographical scope of urban physical areas, extracting the urbanization geographical scope of national land space. The extracted urbanized physical geographical scope provides a basic framework for the analysis of urban spatial patterns and feature extraction.