CSO code and scripts

Food security, particularly soybean, is a significant concern in China due to reliance on imports. This study aims to optimize crop rotations and diet to enhance soybean self-sufficiency. A Cropping System Optimization Model (CSOM) and a Diet-Cropping System Optimization Model (DCSOM) were constructed in order to optimize the crop rotation strategies in 1.7 million cultivated land grids in China. Adjusting crop rotations could produce 89.39 million tons of soybean, raising self-sufficiency rate from 14.2% to 77.4%. On this basis, diet optimization could further reduce soybean demand by 29.33 million tons, thus achieving the soybean self-sufficiency in China. Increased domestic production shifts the environmental footprint from importing countries to China, causing a net global environmental footprint increase, though limited. Additionally, it would reduce greenhouse gas emissions and land use within China, despite higher global nitrogen, phosphorus, and water usage.