高铁网络、城市碳排放强度及空间溢出效应 ——来自长三角地区的证据

基于2006—2018年长三角地区的城市面板数据,采用社会网络分析(SNA)、倾向得分匹配双重差分法(PSM-DID)和空间杜宾模型(SDM)等方法实证检验了高铁开通及高铁网络对碳排放强度的影响及空间溢出效应,研究发现:(1)高铁开通对节点城市碳排放强度产生了显著的减排效应,且随着高铁网络的完善,度数中心度和接近中心度越高的城市碳减排效应越明显;(2)高铁开通通过产业结构效应和技术创新效应降低了碳排放强度;(3)高铁开通提升了节点城市周边地区的碳排放强度。在开通高铁的城市中,度数中心度和接近中心度更高的城市对周边城市的碳排放强度产生了更显著的提升效果,这表明碳排放可能在高铁网络中发生了转移。

Impact of high speed rail network on urban carbon emission intensity and spatial spillover effect

The laying of high-speed railway makes an important contribution to the development of low-carbon economy and the construction of resource-saving and environment-friendly society. In order to clarify the impact of high-speed rail network on urban carbon emission intensity, based on the panel data from 2006 to 2018, taking the Yangtze River Delta as an example, this paper takes the opening of high-speed rail as a quasi natural experiment, and empirically tests the impact of high-speed rail opening and high-speed rail network on carbon emission intensity and spatial spillover effect. The specific conclusions are as follows: the opening of high-speed rail has a significant emission reduction effect on urban carbon emission intensity, and with the improvement of high-speed rail network, the higher the degree centrality and proximity centrality, the more obvious the urban carbon emission reduction effect. Mechanism analysis shows that the opening of high-speed rail has an impact on carbon emission intensity through industrial structure effect and scientific and technological innovation effect. The spatial spillover effect test results show that the opening of high-speed rail has a significant local emission reduction effect on carbon emission intensity, and significantly improves the carbon emission intensity of cities without high-speed rail, which is not conducive to the carbon emission reduction of surrounding cities. Further analysis shows that, in the cities with high-speed rail, the cities with higher degree centrality and nearness centrality have more significant emission reduction effect, and at the same time, the carbon emission intensity of the surrounding cities has also had a more significant improvement effect, which indicates that carbon emission has shifted in the high-speed rail network, resulting in polarization effect.