Impacts of Freight Transport on PM2.5 Concentrations in China: A Spatial Dynamic Panel Analysis

Freight transport policies have been developed to reduce air pollution in China. This paper aims to evaluate the impact of a freight modal shift on PM2.5 concentrations using the panel data of 30 provinces in China over the period 1999-2016. The direct and spillover effects of a freight modal shift on PM2.5 concentrations in China, as well as the effects of other socioeconomic factors, were estimated by employing spatial dynamic panel data models. In particular, the channel through which the freight modal shift might be beneficial in reducing PM2.5 concentrations was examined. The results show that PM2.5 concentrations in China do not only decrease with a modal shift of freight from road to rail in a province, but also and to a larger extent with that in neighboring provinces. However, there exist heterogeneous effects across different regions of China. The interaction between a freight modal shift and energy efficiency may lead to a decrease in the PM2.5 concentrations, but only in the central and western regions. These findings provide suggestions for government policies directed to sustainable development.