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

Abstract

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 Mm³ to 63,572.45 Mm³, 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.

Keywords

Environment effect / Import risk / Multi-objective optimization model / Grain import distribution / China

Data availability

Mendeley Data is available for this paper at https://doi.org/10.17632/6shkbw5ny8.1.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Jian Wang: Writing – original draft, Methodology. Fei Li: Writing – review & editing, Funding acquisition. Yibin Wang: Software, Data curation. Xinjun Yang: Resources, Conceptualization. Yao Zhao: Validation, Formal analysis.

Acknowledgements

This research was conducted under the auspices of National Natural Science Foundation of China (Grants No. 42171197 and 42571325), and the Open Topic of Hunan Key Laboratory of Land Resources Evaluation and Utilization (Grant No. SYS-ZX-202303).

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