Abstract:

Ports are regarded as the main driving force of economic growth in urban areas. The study of port economic spatial structure is of great significance to guide the development of port areas. Based on the four urban scales of mega cities, mega cities, large cities and medium-sized cities, this paper selects 12 ports located in cities of different sizes as the research object, and then based on POI big data, uses Ripley's K function, kernel density estimation and other methods to analyze the agglomeration and distribution mode of port economy under different urban scales, and uses the industrial index method to analyze the circle characteristics of port economy under different urban scales, So as to investigate the spatial structure of China's port economy under the influence of city scale, and explore the development degree and distribution law of port economy. The results show that: 1) The number and scale of industries in most ports will show a decreasing trend as the city size increases. At the same time, due to the rigid demand of the port and surrounding residents for basic services in derivative industries, there are differences in the quantity of various industries distributed around the port. Overall, the number of POIs in derivative industries distributed around the port is significantly higher than that in related service industries; 2) Within a range of 30 kilometers of the core port area, industries of all sizes of cities exhibit agglomeration distribution characteristics due to the influence of industries such as ships, cargo transportation, and comprehensive port services. Among them, the degree of industrial agglomeration in mega cities and large cities varies more strongly with port distance than in mega cities, while the intensity of industrial agglomeration in medium-sized cities does not show a clear pattern with port distance; 3) With the gradual reduction of the city scale level, the number of industries in the circle of the port area has declined. At the same time, the derivative service industries are mainly distributed in the inner circle and the middle circle, while the related service industries are more distributed in the middle circle and the outer circle, and the phenomenon of industrial superposition is more obvious. Based on the above analysis results, the development and construction of Gangkou District in the future should pay more attention to the idea of composite industrial design, create a port economic spatial structure with the characteristics of industrial complex, and at the same time follow the concept of land intensification to promote port economic concentration and structural optimization. The port economic distribution scope should give priority to development within 30 km.

Key words: city size, POI data, port economy