Urban functional district Identification based on OSM Road Network and POI data: A case study of Changsha City center

Due to the distribution space and corresponding differentiation of various functional activities in the city, in order to accurately identify the urban functional land, understand the urban internal spatial structure, and provide decision-making basis for urban planning and management. In this paper, the study area is irregularly segmented based on the road network, and the kernel density of various POI data is weighted by the geographical entity's land area and public awareness, so as to establish a quantitative identification method for urban functional area, and output the identification results of urban functional area for analysis and research. The results show that: (1) the functional distribution of urban blocks shows obvious centripetal agglomeration characteristics. From the city center to the periphery, the functional complexity of urban blocks is reduced and the agglomeration is weakened. Tianxin district, Furong District and Yuhua district are evenly distributed, which is favorable for urban development. (2) The main urban area of Changsha has a large number of mixed-use land with the combination of the two functions, and the mixed-use land with commercial land as the dominant function is the largest.