Impact of Economic and Environmental Factors on O₃ Concentrations in the Yangtze River Delta Region of China

The concentration of atmospheric ozone (O-3) pollution is showing a rapid growing tendency, and O-3 pollution has become one of the bottleneck issues that restrict the continuous improvement of air quality in China. In this study, we first identified the primary factors based on the source apportionment of O-3, then used factor analysis to divide these selected factors into economic and environmental categories. The geographical detector model was used to analyze the impact of factors and their interactions on O-3 concentration in 41 cities in the Yangtze River Delta (YRD) region in 2020. The results showed that forest coverage ranked first among all the detected factors, suggesting a strong relationship between the regional O-3 concentration and forest coverage. The driving factors of economic activity were ranked as follows: actual utilization of foreign capital (0.400) > gross domestic product (GDP) per capita (0.387) > proportion of tertiary industry (0.360) > urbanization rate (0.327) > per capita consumption expenditure (0.194) > research and development (R&D) of full-time equivalents of industrial enterprises above designated size (0.182) > number of industrial enterprises (0.126). The interaction between any two factors enhanced their influence on O-3 concentration more than any single factor, indicating that the variability of regional O-3 concentration was an outcome of a combination of multiple factors. This study could provide recommendations for the prevention and control of O-3 pollution and the development of ecological integration in the YRD region.