A Study on the Urban Multi-center Spatial Structure Based on POI Data—Taking Guangzhou as an Example

Since the twenty-first century, China’s urbanization has entered a period of rapid development. With the expansion of the city scale and the rapid population aggregation, the urban activity characteristics and development trend become more and more complex, and various “urban diseases” problems occur frequently, such as traffic congestion in the city center due to the excessive concentration of urban functions, low land utilization rate leading to housing shortage and soaring land prices. In order to alleviate the above problems, in recent years, most cities in our country adopt the multi-center development strategy for the spatial structure, but the multi-center theory still suffers from limitations in its localization applications. Compared with the traditional survey research methods, POI data brings about new insights and innovative methods for the study of urban spatial structure, with smaller measurement errors. Under the background of a huge subway transportation system and the construction and development of Guangdong, Hong Kong and Macao Bay area, the characteristics of its urban spatial structure and the development degree and trend of each center will be more special. This paper took Guangzhou City as an example, which is a megacity with rapid expansion of urban space. Based on the reorganized POI data crawled from Baidu map open platform, we adopted spatial kernel density analysis method and DBSCAN clustering method. Considering the multi-center structure characteristics of Guangzhou city, using ArcGIS software, this paper studied the overall layout of Guangzhou City as well as its structural characteristics of the following five kinds of urban functional spaces: living, business, employment, culture education and leisure. The results of this study showed that: (1) The polycentric spatial structure of Guangzhou is composed of many factors; (2) there exists a clear evidence that the urban spatial structure of Guangzhou has a typical multi center structure, with a circular distributions of denser inside and sparser outside; (3) different functional spaces present a multi-center structure with certain differentiations; (4) the centers of Guangzhou can get rid of unbalanced development problems by means of “unban coordination”.