“流空间”视角下高速公路交通流网络结构特征及其形成机制——以广东省为例

交通流是城市经济联系最显性的表现,为更清晰地识别城市网络结构提供了新视角。本研究采用高速公路联网收费数据作为交通流“关系数据”,综合图论、社会网络分析法（SNA）和GIS空间分析,以广东省为研究区域探索高速公路交通流网络空间结构特征,并利用QAP回归法探究影响网络形成的因素。结果表明：① 广东省高速公路已形成典型的网络式空间结构,具有“小世界”网络效应。其节点度值服从幂律无标度分布,交通出入量基本平衡,节点重要性自区域中心向外围递减;网络有向边权值等级差异显著,优势交通流具有“向心指向”特征和距离依赖性。② GDP、常住人口、社会消费品零售总额、县区间行驶距离等已成为影响广东省高速公路交通流网络形成的重要因素。其中人口因素是影响城市间交通流动的主要因素,网络形成受制于距离因素,消费因素逐渐成为刺激城市间交通流动的强大动力。③ 广东省高速公路交通流动模式分为邻近指向型、中心指向型和等级指向型三种,以邻近指向型为典型模式。研究结果对于揭示交通流动规律,丰富城市网络理论,推动道路合理规划和区域协调发展具有重要理论和实践意义。

Spatial structure and formation mechanism of expressway traffic flow network based on space of flows:A case study of Guangdong province

Traffic flow is the most powerful indicator to map urban economic connections, which provides a new perspective to identify urban network spatial structure clearly. This study uses Guangdong's data to explore the spatial structure of expressway network based on theory of synthesized graph, social network analysis (SNA) and GIS spatial analysis. QAP regression method is used to explore the factors which influence the network characteristics. The results show that: (1) The Guangdong's expressway forms a typical network spatial structure with “small world” network effect. The out-degree and in-degree values of network nodes follow the power law scale-free distribution, traffic volume is basically balanced, and the importance of nodes decreases from regional center to periphery. There are significant differences in the weights of directed edges, and the dominant traffic flows have the characteristics of “centripetal direction” and “distance dependence”. (2) The results of QAP regression show that the character of Guangdong's expressway traffic flow network is significantly affected by GDP, resident population, total retail sales of consumer goods, and the distance. Population is the most powerful factor which affects inter-city traffic flows, the formation of network is restricted by distance, and the consumption factor is gradually becoming a powerful driving force to stimulate the inter-city traffic flows. (3) The traffic flow patterns of expressway in Guangdong are divided into three types, namely, proximity-oriented, central-oriented and hierarchical-oriented. The proximity-oriented traffic flow is typical, which is widely distributed in the province; the central-oriented traffic flow is concentrated in the Pearl River Delta urban agglomeration; and the hierarchical-oriented traffic flow is mainly distributed between Guangzhou and Qingyuan, and between Shenzhen and Shantou. The research results have important theoretical and practical significance for revealing the laws of traffic flow, and enriching urban network theory. Furthermore, it provides theoretical support for scientific road planning and coordinated regional development.