Research on the Impact of Heterogeneous Environmental Regulation on the Coordinated Development of China's Water-Energy-Food System from a Spatial Perspective

Water resources, energy, and food are fundamental resources for ensuring human social development. The coordinated development of these resources contributes to improving the quality of the social environment, promoting harmony between humans and nature, and achieving economic, social, and ecological sustainability. This study utilizes panel data from 30 provinces in China from 2003 to 2020. Using a coupled coordination degree model, the coupling coordination degree of the Water-Energy-Food (WEF) system is calculated, and the spatiotemporal evolution and social network connections of WEF coupling coordination are analyzed. The spatial Durbin model is employed to investigate the spatial spillover effects of heterogeneous environmental regulation on the coordinated development of the WEF system. The mechanism model is used to explore the pathways through which heterogeneous environmental regulation influences the coordinated development of the WEF system. The results of this study demonstrate that the coupling coordination index of China's provincial-level WEF system has shown a steady upward trend, except for a slight decline in a few years. Over the research period, there has been a significant improvement in regional coupling coordination levels. There are large differences in the level of WEF coupling coordination among different regions, with a distribution pattern of south > north and east > west. Both formal and informal environmental regulations have significant positive effects on the coupling coordination development of the WEF system, as well as significant positive spatial spillover effects. Formal environmental regulation has a stronger impact compared to informal environmental regulation. Foreign direct investment and industrial structural upgrading are important pathways for environmental regulation to promote the coordinated development of the WEF system. Both formal and informal environmental regulations can promote the coordinated development of the WEF system by facilitating foreign direct investment and industrial structural upgrading. This study not only provides important scientific evidence and decision-making references for policymakers in formulating environmental regulation policies but also offers new evidence support for the theory of regional development disparities.