The spatial spillover effect of urban sprawl and fiscal decentralization on air pollution: evidence from 269 cities in China

Air pollution is an important factor affecting the quality and sustainability of the development of China's economy, and urban sprawl is also a typical by-product of the non-intensive development of urban land. At the same time, Chinese-style fiscal decentralization promotes urban sprawl through top-down yardstick competition, which has a serious impact on air pollution. Therefore, exploring the effect of fiscal decentralization and urban sprawl on air pollution is of great significance for regulating local government behavior, curbing urban sprawl, and accurately identifying the causes of air pollution. The dynamic spatial Durbin model with economic geography weight matrix is employed to analyze the direct and moderating effects of fiscal decentralization and urban sprawl on air pollution on the basis of 269 prefecture-level cities in China from 2004 to 2018. The results show that air pollution has a significant retarded time effect and space spillover effect. Both fiscal decentralization and urban sprawl have contributed significantly to air pollution. The moderating effect of urban sprawl and fiscal decentralization on air pollution is significantly positive. From the short-term effects, the coefficients of the total spillover effect, direct spillover effect, and indirect spillover effect of urban sprawl and fiscal decentralization on air pollution are significantly positive, respectively. In terms of long-term effects, the total spatial spillover effect of urban sprawl and fiscal decentralization on air pollution is significantly negative, while the direct and indirect effects of those are negative but not significant. Further research finds that there is significant regional heterogeneity in the influence of urban sprawl and fiscal decentralization on air pollution.