城市群多要素外向联系网络结构——基于长江中游城市群-长江经济带的实证

Multi-Outward Connection Networks of Urban Agglomeration: An Empirical Study from Middle Reaches of Yangtze River to Yangtze River Economic Belt

大数据分析已成为新时期理解城市网络的关键。基于交通、信息大数据,通过SNA、SSI、Modularity等方法分析长江中游城市群外向联系网络结构及影响因素,结果显示:(1)空间异质性明显,极化作用突出。普铁网络形成以周边城市为主的"π"型空间联系格局,高铁网络廊道效应显著,呈现以沪昆、汉沪蓉高铁为轴线的侧"V"型联系格局,信息网络形成以武汉、长沙、南昌为核心向外放射状空间联系格局。SSI均小于0.1,空间极化效应明显。(2)拓扑结构上,普铁、信息网络单核结构显著,高铁网络双核结构突出,综合网络显现多核结构。(3)社区结构上,普铁和高铁网络社区结构明显,信息和综合网络未形成明显的社区结构。(4)城市规模对长江中游城市群外向联系网络发挥关键作用,地理距离、行政等级以及城市职能也会产生不同程度的影响。

Big data analysis has become the key to understanding urban networks in the new era. Based on the data of railway and high-speed railway in the Yangtze River Economic Belt and Baidu index, the network structure characteristics and influencing factor were analyzed by means of social network analysis, spatial structure index and modularity, the results show that:(1) Spatial heterogeneity is significant and polarization is prominent. The general railway network forms a "π" spatial connection pattern dominated by surrounding cities. The high-speed rail network has a significant corridor effect, showing a side "V"-shaped connection pattern with the Shanghai-Kunming and Han-Shanghai-Chengdu high-speed rails as the axis. The information network is formed in Wuhan, Changsha, and Nanchang are the core and radial spatial connections. SSI is less than 0.1, and the spatial polarization effect is obvious.(2) Topological structure, the general railway and the information network form a single-core structure with Chenzhou and Chengdu as the core respectively, the high-speed railway forms a dual core structure with Hangzhou and Jinhua centers, and the comprehensive network forms a multi-core with Shanghai, Hangzhou and Chenzhou, etc. as the center structure.(3) In terms of community structure, the network community structure of universal railway and high-speed railway is significant, while the network community structure of information and comprehensive network is not.(4) City size plays a key role in the outward connection network. Geographical distance, administrative level and city functions also have different degrees of influence.