Development of green and low-carbon agriculture through grain production agglomeration and agricultural environmental efficiency improvement in China

Grain production agglomeration (GPA) is the development trend of grain production all over the world, and it is also an important way to promote grain growth and low-carbon development of agriculture. However, in-depth research on whether the GPA can increase the agricultural environmental efficiency and the influencing mechanisms is still lacking. Based on China's provincial data from 1990 to 2019 and the superefficiency DEA model, this study measures the level of GPA and the environmental efficiency of grain production (EEGP) in different grain production functional areas of China. An econometric methods are also used to empirically analyse the impact GPA on the EEGP. The results shows that the level of GPA in China is steadily increasing, and the impact of GPA on EEGP follows a U-shaped trend of initially declining and then rising. China's GPA has exceeded the minimum value of the U-shaped curve and is currently in the stage of promoting the EEGP. Specifically, the level of GPA in China's main grain-producing areas is higher than that in main grain-marketing areas and grain production-marketing balanced areas, and the GPA in main grain-marketing areas and grain production-marketing balanced areas have not yet crossed minimum value of the U-shaped curve. The GPA affects EEGP through farmland scale management and agricultural technology spillover. This study offers a new perspective to explain the changes in China's EEGP, and also provides reference for the EEGP in different regions of the world.