Efficiency and productivity of air pollution control in Chinese cities

The booming urbanization and industrialization have exerted much pressure on China's urban air pollution control (APC). To unearth the dynamic evolution of APC, this work draws evidence from 106 Chinese cities based on integration of efficiency and productivity. Specifically, a generalized environmental production technology (GEPT) is first developed by considering both heterogeneity of abatement technology across cities and heterogeneity of emission reduction of different pollutants. Given that both generation and treatment processes of air pollutants are important aspects of emission reduction, a network extension of GEPT is conducted to measure the system and two sub-stages efficiencies of APC. Finally, a new global network Malmquist index is proposed to identify the dynamic evolution of APC, which decompose the productivity of system into the product of technological change and efficiency change in two sub-stages. The findings show that the efficiency of APC in China presents an upward trend during the study period. The treatment sub-stage has greater potential for improvement than the generation sub-stage. Moreover, the productivity of China's APC improves 8.9%, and only 28.3% of the cities positively change in both technology and efficiency. The policy recommendations are proposed accordingly.