Decoupling economic development from municipal solid waste generation in China’s cities: Assessment and prediction based on Tapio method and EKC models

This study uses the Tapio elastic decoupling analysis method and an empirical model of the environmental Kuznets curve (EKC) to analyze the decoupling between municipal solid waste (MSW) generation and economic development in 285 of China’s cities from 2002 to 2017. The decoupling analysis results show that the decoupling states in China’s cities generally improved first and then deteriorated in 2002–2017. The proportion of cities experiencing deterioration of decoupling states had increased to 60.00% by 2014–2017, and cities with a higher economic development level generally had more serious deterioration. The empirical test results support the N-shaped EKC hypothesis of MSW, which can explain why the decoupling state changed from improvement to deterioration. The difference of the economic level of sample cities (which determines their position on EKC) can also explain the spatial heterogeneity of the decoupling state and its changes; for example, the proportion of cities that have crossed the inflection point of Tapio decoupling elasticity (the per capita GDP is 13,130.89 yuan) to enter the deterioration stage is highest (100/101) in the economically developed eastern region, and is lowest (66/75) in the economically backward western region of China. In general, the empirical results of EKC can effectively support and explain the results of decoupling analysis.