Cropland’s northward shift widened the mismatch between cropland distribution and natural geographic conditions in China from 1980–2020

In recent years, the illogical flow of cropland resources in China has increased the mismatch between cropland resources and natural geographic conditions (NGCs) posing a threat to national food security. This paper investigates the spatial distribution pattern of NGCs, by utilizing land use data, it comprehensively studies the variation of cropland resources from 1980 to 2020, and meticulously analyzes the matching situation and change trends of cropland resources and NGCs. The results show that: (1) There are remarkable disparities in NGCs among different natural areas. The natural conditions in the South and East China Regions are far superior to those in the North and West regions. (2) Cropland has gradually flowed from the wet-hot southern regions to the warm-dry northern regions, and the quality of cropland decreased. From 1980 to 2020, the cropland of the Northeast Region and the Northwest Region has increased by 87,183 km2, while the total cropland area in the South China Region, the Middle and lower reaches of the Yangtze River Region, and the Huang-Huai-Hai Region decreased by 57,362 km2. The gravity centre of cropland overall shifted 82.2 km northwestward. (3) The distribution of cropland does not align with that of NGCs, and the mismatch is further intensifying with cropland changes. The study results suggest that the strict cropland acquisition and compensation policy norms should consider the characteristics of regional NGCs. Moreover, cropland resources should be sustained balance within natural areas or the 10 large regions, which have great significance for protecting the quantity and quality of cropland resources.