Impact of technological innovation and industrial-structure upgrades on ecological efficiency in China in terms of spatial spillover and the threshold effect
Authors: Huang Meng , Ding Rijia , Xin Chunhua 
Published: December 2020

Abstract
In the past 40 years, China's rapid industrialization has resulted in remarkable social progress and regional economic prosperity but also has caused problems, such as excessive resource consumption and environmental pollution. Ecological efficiency is an important indicator of whether economic efficiency and environmental efficiency are balanced. Exploring ecological efficiency is vital for achieving sustainable development, as technological innovation, industrial structure upgrading, and ecological efficiency are probably related. However, there has been little research on the relationships among them. In this study, we used the super-efficiency slacks-based model (SBM) involving undesirable output to calculate the ecological efficiency of 30 provinces in China from 2008 to 2017. We found that China's ecological efficiency has risen, fallen, then fluctuated, and that there were significant spatial differences. Then, we used 3 spatial econometric models for comparative analysis, which revealed that the independent effects of technological innovation on ecological efficiency was significant and negative; however, technological innovation demonstrated a strong positive effect in tandem with industrial structure upgrading, and industrial structure always had a positive effect on ecological efficiency. On this basis, we added the cross-item of technological innovation, and industrial-structure upgrades had a significant and positive impact on ecological efficiency, which was significantly greater than the independent effect of technological innovation and industrial-structure upgrades. To explore the mechanism of industrial-structure upgrading and technological innovation on regional ecological efficiency, we set the first 2 as threshold variables. We found that there is in fact a threshold effect of technological innovation and industrial-structure upgrading on ecological efficiency due to the mismatch of periods. These results provide a theoretical rationale for China to formulate strategies to improve ecological efficiency. Integr Environ Assess Manag 2021;17:852–865. © 2020 SETAC
KEY POINTS
China's ecological efficiency calculated by the super-SBM model involving undesirable output shows a trend of rising, falling, then fluctuating and that there are significant spatial differences. This article uses the spatial econometric model to prove that the independent effects of technological innovation include a significant and negative impact on ecological efficiency, but a positive one for synergy of upgrades to industrial structure and industrial structures boost ecological efficiency. The cross-item of technological innovation and industrial-structure upgrades has a significant and positive impact on ecological efficiency that is significantly greater than the independent effect of technological innovation and industrial-structure upgrades. The panel threshold model is used to empirically analyze the pulling effect of technological innovation, and industrial-structure upgrading on the ecological efficiency may involve the threshold effect due to a period of mismatch.