The Effect of Heterogeneous Environmental Regulations on Carbon Emission Efficiency of the Grain Production Industry: Evidence from China’s Inter-Provincial Panel Data

Examining the impact of heterogeneous environmental regulations on the carbon emission efficiency of the grain production industry will help to provide a theoretical basis and decision-making reference for achieving the goal of carbon peaking and sustainable agricultural development. Based on the panel data of 30 provinces in China, the DEA-SBM method was used to measure the grain production industry’s carbon emission efficiency from 2011 to 2019. Separating environmental regulations into formal environmental regulations and informal environmental regulations in two parts, then the two-way fixed effect model, threshold effect model, and intermediary effect model are used to test the influence of heterogeneous environmental regulations on the grain production industry’s carbon emission efficiency. The results show that: (1) the grain production industry’s carbon emission efficiency continues to improve but still has space for improvement. (2) the relationship between formal environmental regulations and the grain production industry’s carbon emission efficiency exhibits a “U-shaped” curve; informal environmental regulations have a significantly positive effect on improving the grain production industry’s carbon emission efficiency. The conclusion is still valid after the robustness test. (3) A threshold mechanism test found that there is a single threshold effect between the formal environmental regulations and the grain production industry’s carbon emission efficiency, but it does not cross the “U” inflection point. (4) there is a “U” shaped non-linear mediating effect in the influence of formal environmental regulations on the grain production industry’s carbon emission efficiency; informal environmental regulations also have an intermediary transmission path of production agglomeration of the grain production industry. This study supplies a new perspective for promoting the grain production industry’s carbon emission efficiency.