Does Upgrading of Industrial Structure Drive Economy to "Decouple" from Environment: an Empirical Analysis Based on the Data of Prefecture-Level Cities in China

Based on the panel data of 325 prefecture-level cities in China from 2015 to 2017, we first calculate the decoupling elasticity and classify the "decoupling" and "hooking" relationship between economy and environment. Then, taking different measurement standards of urban air quality as threshold variables, the nonlinear relationship between industrial structure upgrading and economy-environment decoupling is investigated by constructing panel threshold regression models. As there are differences between cities in nature and humanities, it should be discussed whether urban heterogeneity can affect the relationship between industrial structure upgrading and economy-environment decoupling. The results show that the impact of industrial structure upgrading on economy-environment decoupling elasticity has threshold characteristics based on AQI mean value, PM10 mean value, and PM10 peak value. The heterogeneity of "natural endowment" and "humanistic endowment" in cities can influence the nonlinear relationship between industrial structure upgrading and economy-environment decoupling. The upgrading of industrial structure in inland cities will aggravate the "hooking" relationship between economy and environment, while for coastal cities, as long as the average PM10 is not higher than 41.170, the upgrading of industrial structure will be beneficial to promote the economy-environment decoupling.