Optimizing import patterns to reduce the environmental effects and risks of China’s grain imports

• China’s grain imports ease global environmental pressures, but impacts vary by crop. • China’s grain import risk is declining, yet maize and soybeans risks remain high. • Optimizing China’s grain imports can reduce import risks and environmental impacts. Grain imports are an important means of ensuring China’s food security, but they also create dual global challenges in terms of environmental spillover effects and supply risks. It is crucial to balance the environmental sustainability with supply stability in grain import strategies. Therefore, based on environmental footprint, country-specific risks, and market concentration, this study assessed the global environmental impacts and potential supply risks of China’s grain imports, and used a multi-objective optimization model to identify improved import strategies. The results showed that from 2000 to 2020, the global cultivated land savings caused by China’s grain imports increased from 1,859.70 kha to 18,209.11 kha, water saving increased from 3,665.43 Mm 3 to 63,572.45 Mm 3 , and GHG emission reduction increased from 1,282.30 kt to 13,811.94 kt, but these effects varied substantially across crops. Overall, China’s grain import risk (CGIR) followed a rise-then-decline pattern, with periodic certain cyclical fluctuations. Import risks differed significantly across crops, with maize (mainly from the United States and Ukraine) and soybeans (primarily from the United States and Brazil) remaining at elevated risk levels. It was difficult to reconcile environmental impacts and import risk through adjustments to grain import patterns in a single-objective setting. Under dual environmental and risk constraints, adjusting China’s grain import strategy reduced cultivated land consumption by 4.92%, GHG emissions by 5.02%, and import risk by 36.55%, despite increasing water consumption by 5.41%. This study offers policy-relevant recommendations to help alleviate the tension between grain import security and sustainable development.