铁路高速化对长三角城市群区域空间联系格局的影响

为探讨高速铁路线网格局及运营组织对城市空间重构的影响,以长三角城市群为实证,采用2008及2018年长三角城市群铁路时刻数据,对比分析普速铁路与高速铁路对区域可达性及城市联系紧密度的影响。结果表明:高速铁路的运营一方面改善了城市间铁路旅行时间,另一方面产生"时空收敛"的不均衡效应,铁路可达性水平以沪宁通道为中心向外围递减;沪、宁、杭、合、甬等中心城市以高速铁路网络为依托重塑一日交流圈,其范围沿高速铁路延伸且重叠范围不断扩大;高速铁路影响城市空间联系并推动区域空间重构,区域联系强度呈现出多核心、多层次的结构特征,并呈现向网络化结构发展的趋势;核心区域由以上海为核心的"一体两翼"结构拓展为沪宁杭多向联系的"黄金三角"结构,其他不同等级节点城市依托高速铁路连接,在此基础上形成"中心—网络"的组织模式。

Assessing the Impacts of High-speed Rail on Regional Spatial Structure: A Study of Yangtze River Delta Urban Agglomeration

With the development of economic globalisation and the intensifying of regional integration, an urban agglomeration is becoming an important platform for international competition and cooperation. During this process, the transport facility, especially high-speed rail (thereafter HSR) acts as an essential medium for regional connectivity while generating essential impacts on the formation and optimisation of the regional spatial pattern. Using railway time data of 2008 and 2018, this paper studies the railway passenger transport service capacity of Yangtze River Delta urban agglomeration by comparing accessibility and linkage intensity level between traditional rail and high-speed rail. Based on the above investigation, this research attempts to measure how the network pattern and operational organisation mode of HSR work to reshape and develop urban spatial structure. The results are demonstrated as follows. (1) HSR has substantially shortened the travel time between cities and improved the accessibility of transport services by generating a “time-space convergence” effect, thereby leading to a shrinkage of space and time. Generally, the HSR has improved the overall railway passenger transport service capacity in the research area. The highest level of accessibility centres on the Shanghai-Nanjing channel and is declining from the core area to the peripheral region in Yangtze River Delta urban agglomeration. (2) Shanghai, Nanjing, Hangzhou, Hefei, Ningbo have formed different daily communication areas, which expand along the HSR, causing the overlapping area to increase. (3) The linkage intensity pattern in the Yangtze River Delta urban agglomeration can be characterised as multi-level and multi-core, boosting a networked regional structure. (4) By influencing urban spatial linkage, the HSR promotes regional spatial reconstruction to a large extent. The spatial structure of Yangtze River Delta urban agglomeration is expanded from the “one body two wings” structure with Shanghai as the core to the “golden triangle” structure which connects Shanghai, Nanjing, and Hangzhou. The implementation of HSR has accelerated the flow of factors, enhanced transport efficiency and promoted multi-level integrations within the agglomeration. In the future, the construction of railway corridors in marginal areas should be strengthened to expand the coverage of railway service and thus to bridge the gap in accessibility. Furthermore, it is crucial to attach importance to optimising the spatial organisation of HSR in the core area with the aim of enhancing passenger transport capacity, and encouraging the optimal allocation of resources in the region.