长三角城市群“空间流”网络结构特征--基于公路运输、火车客运及百度指数的综合分析

“SPATIAL FLOW”NETWORK STRUCTURAL FEATURES OF THE URBAN AGGLOMERATION IN THE YANGTZE RIVER DELTA:A COMPREHENSIVE ANALYSIS BASED ON ROAD TRANSPORTATION,RAILWAY PASSENGER TRANSPORTATION,AND BAIDU INDEXES

信息技术的应用与社会信息技术的传输,使大量的要素(人流、物流、信息流)在城市群空间内集聚与扩散,加密城市群空间内城市联系。在基于公路运输、普通列车、高速列车以及百度指数4个要素的综合分析基础上,对长三角城市群"空间流"网络结构特征进行探析。研究结果表明:(1)长三角城市群区域内城市联系虽具备了网络化规模,但城市间的联系不均衡,以上海、南京、杭州等城市为多中心的协调网络发展格局特征明显;(2)长三角城市群16个核心城市"空间流"特征呈现三角形网络结构,其三角形的顶角分别由上海(沪)、南京(宁)与杭州(杭)3个核心节点城市构成。在空间结构内部,形成若干次级城市网络连线;在空间分布上,北翼网络化程度较高于南翼线性联系程度,区域联系强度以"沪—宁"、"沪—杭"沿线向两侧递减;(3)上海、南京、杭州、苏州、无锡5个核心城市排名处于网络中心的前列,扬州、南通、泰州、舟山等周边城市相对靠后,这与区域经济发展过程的"吸虹效应"有关,随着区域经济一体化程度的加深,中心城市会向周边地区提供服务与经济辐射,完善整个长三角城市群网络体系。

The application of information technology and transmission of social information technology make a large number of elements,including population flow,material flow and information flow,gather and spread within the urban agglomeration. The links among agglomerated cities are strengthened as well. Based on the comprehensive analysis of road transportation,common train,high-speed train,and Baidu indexes,this paper analyzes the ‘spatial flow ＇network structural features of the urban agglomeration in the Yangtze River Delta.Results indicate the followings.（1） An imbalanced relationship is found among the cities although network connections have been established within the Yangtze River Delta urban agglomeration. The network development pattern is remarkably centered in Shanghai,Nanjing,and Hangzhou.（2） The ‘spatial flow＇of the 16 core cities in the Yangtze River Delta urban agglomeration shows a triangle network structure,and the vertex angles are composed of three core nodes,such as Shanghai（ Hu）,Nanning（ Ning）,and Hangzhou（ Hang）. Numerous network connections have also been established among secondary cities within the spatial structure. In terms of spatial distribution,the network connection degree in the Northern region is higher than the linear connection in the Southern region,and the connection degree decreases along ＂Hu-Ning＂and ＂Hu-Hang. ＂（3） The five core cities,including Shanghai,Nanjing,Hangzhou,Suzhou,and Wuxi,are ranked in the forefront of the network.Meanwhile,Huzhou,Nantong,Taizhou,Zhoushan,and other peripheral cities are ranked backward. This finding is associated with the ‘connected vessels effect＇during the development of regional economy. With the development of regional economic integration,the central city will provide services and economic radiation to the surrounding areas and improve the network system of the Yangtze River Delta urban agglomeration.