The effect of high-speed railway construction on urban carbon emission intensity and mechanism under the perspective of multidimensional heterogeneity: A quasi natural experiment based on 281 cities at prefecture level and above in China

Abstract

[Objective] As the low-carbon advantage of high-speed railway is conducive to the early realisation of the strategic goal of “carbon neutrality and carbon peaking”, it is of great significance to explore the low-carbon emission reduction effect of high-speed railway construction and its influencing mechanism from a multi-dimensional heterogeneity perspective. [Methods] Based on the panel data of 281 prefecture-level and above cities in China from 2006 to 2020, this study considered the construction of high-speed railway as a quasi-natural experiment, and adopted the multi-period difference-in-differences method, spatial difference-in-differences method, and mediation effect model to systematically investigate the direct effect and spatial spillover effect of the construction of high-speed railway on the intensity of carbon emission in cities and mechanism. [Results] The study found that: (1) The construction of high-speed railway made a significant contribution to the reduction of urban carbon emission intensity, and there was a four-year delay period in this effect on average; (2) The emission reduction effect of high-speed railway was significant in western cities, growing and declining resource cities, and non-hub cities, but not in other regions and types of cities; (3) The results of mechanism test show that the construction of high-speed railway can reduce the carbon emission intensity of cities by increasing the level of urban economic agglomeration and scientific and technological innovation; (4) The results of spatial difference-in-differences analysis show that the negative “siphoning effect” of high-speed railway construction on the carbon emission intensity of neighboring cities was greater than the positive “diffusion effect”. [Conclusion] Therefore, for the construction of high-speed railway, the state should keep the existing stock and maintain the constant growth so that high-speed railway can continue to play a role in low-carbon development and emission reduction, and local governments should also take into account local conditions, formulate emission reduction policies reasonably, and promote the coordinated development of regions while realizing the carbon emission reduction target of cities.

Keywords

• |high-speed rail|carbon emission intensity|quasi-natural experiment|difference-in-differences model|mediation effect model