Evaluating the Effectiveness of Urban Sprawl in Reducing Air Pollution: Evidence from Chinese Cities

Urban sprawl has a significant impact on the air environment. In this paper, taking the two representative pollutants, PM2.5 and CO2, as examples, we used the data from 2010 to 2022 and empirically examined the specific impact of urban sprawl on air pollution. Overall, urban sprawl increases pollutant emissions and exacerbates air pollution. In this process, private car usage is an important mechanism. Moreover, there is significant heterogeneity in the effects of urban sprawl on air pollution. The pollution effect of urban sprawl on the air environment is significant in the western region and small cities. Besides, urban sprawl also has a nonlinear effect on air pollution. Specifically, urban sprawl has a U-shaped effect on air pollution. Currently, the effects of urban sprawl on emissions of both pollutants lie on the right side of the curve.