Size-hierarchy and network structure analysis of urban system in the Yellow River Basin using multi-source data
The key to achieving the goal of high-quality development in the Yellow River Basin lies in build-ing a reasonable urban system.Quantitative research on the urban system of the Yellow River Basin from the perspective of size hierarchy and network structure is not only conducive to analyzing the structural character-istics of the urban system,but also has theoretical significance to deepen the understanding of the urban system from the perspective of function and relationship.Based on macro statistics data,micro enterprise data and traffic big data,87 cities(autonomous prefecture)in the Yellow River Basin are taken as the basic unit,and the rank-size rule,urban gravity model and social network analysis are integrated.From two aspects of scale and connection,this paper explores the size-hierarchical and network structure characteristics of the Yellow River Basin urban system under the three dimensions of urban node,development axis and spatial structure,and the relationship between urban size hierarchy and network structure.The results show that:1)The urban system of the Yellow River Basin presents the characteristics of dense small and medium-sized cities,scattered high-level sub cities and multi center distribution.The overall scale level tends to be balanced,and the scale status of the first city is not prominent.2)The development axis of the Yellow River Economic Belt,dominated by the con-nection between Lanzhou,Xi'an,Zhengzhou,Jinan and Qingdao,has been formed,and the"Ψ"spatial pattern has been formed along this axis.The network centrality gradually increases from the upstream to the down-stream,and forms dense sub-networks in Shandong and Henan provinces.However,the overall connection strength is not high,and the transportation connection is stronger than the economic connection.3)The co-ordination degree of city size hierarchy and network structure in the Yellow River Basin is relatively high,and they show a flattened S-shaped curve relationship,which can be divided into three stages:Low-level low-speed coupling,medium-level high-speed coupling and high-level low-speed coupling.Population,economy and land use scale all have significant positive effects on network centrality.
urban systemnetwork structuresize hierarchysocial network analysisthe Yellow River Basin