Industrial upgrading and its influence on green land use efficiency.

The rational use of land is an important guarantee for the sustainable development of resource-based cities. First, this paper uses the panel data of 115 resource-based cities in China from 2004 to 2018 to measure green land use efficiency (GLUE) by SBM model and Metafrontier-Malmquist productivity index model. Secondly, it analyzes the industrial upgrading from the perspectives of the optimization of industrial structure and the rationalization of industrial structure to explore the impact mechanism of industrial upgrading on GLUE. Furtherly, the heterogeneity analysis is carried out from the following two perspectives: exploring the impact of industrial upgrading on GLUE under different types of urban samples; using the quantile model to analyze the impact of industrial upgrading under different GLUE quantiles. The main conclusions of this study are as follows: (1) both the optimization of industrial structure and the rationalization of industrial structure promote the improvement of GLUE. The robustness test and instrumental variable method support this conclusion. (2) For different types of resource-based cities, the rationalization and optimization of industrial structure have positive coefficients in regeneration cities, growing cities, and declining cities, but have a negative effect on mature cities. (3) In all quantiles, the effects of industrial structure optimization and industrial structure rationalization are positive. However, with the increase of quantiles, the role of industrial structure optimization gradually decreases. The role of industrial structure rationalization gradually increases. Meanwhile, there is an obvious threshold effect when taking resource endowment as the threshold variable. This paper provides a theoretical reference for the transformation and development of resource-based cities.