Reexamining the relationship between urbanization and pollutant emissions in China based on the STIRPAT model

Understanding the relationship between urbanization and pollutant emissions in China is of great significance to realizing sustainable development. Previous studies focused on the relationship between urbanization and air pollutants in China. However, the relationship between urbanization and industrial or domestic pollutants remains unclear. In this paper, we used the stochastic impacts by regression on population, affluence, and technology (STIRPAT) model to examine whether an environmental Kuznets curve (EKC) relationship exists between urbanization and pollutant emissions, including industrial wastewater, industrial SO₂, industrial soot (dust), and domestic garbage based on panel data for 277 prefecture-level cities in China from 2003 to 2015. We found that industrial soot (dust) emissions and domestic garbage increased by 83.0% and 43.5%, respectively, whereas industrial wastewater discharge and SO₂ emissions decreased by 7.4% and 10.5%, respectively. The identified inverted U-shaped relationship between the urbanization ratio (i.e., percentage of the population living in urban areas) and industrial pollutants supports the EKC hypothesis. However, the domestic garbage volume increased with increasing urbanization ratio. In the future, more attention should be paid to the prevention and control of domestic pollution. In addition, small and medium-sized cities should reduce pollutant emissions and determine effective ways to achieve sustainable development.