Improvement of environmental performance and optimization of industrial structure of the Yangtze River economic belt in China: going forward together or restraining each other?

Based on the panel data of eleven provinces and cities in the Yangtze River Economic Belt of China from 2008 to 2018, both the optimization index of the industrial structure and environmental performance indexes are calculated. Then, the impact of industrial structure optimization on the improvement of ecological environmental performance was investigated by applying the static panel model and threshold model. The results show that the optimization of the industrial structure of the Yangtze River Economic Belt has a significant role in promoting the improvement of environmental performance in general. Still, the rationalization of the industrial structure has a single threshold effect. The upgrading of regional industrial structure in the middle reaches of the Yangtze River and the rationalization of regional industrial structure in the Yangtze River's upper reaches are more conducive to improving ecological environment performance. Therefore, in the transformation and upgrading of the industrial structure of the Yangtze River Economic Belt, the downstream region should strengthen scientific and technological innovation, strive to break through the core and critical technologies, and mainly build clean and efficient green service industries.