Impacts of global trade on cropland soil-phosphorus depletion and food security

Globalization intensifies the demand for agricultural products from specific regions, resulting in intensive farming practices that can exacerbate local cropland soil phosphorus (P) depletion, thereby undermining long-term food security. By integrating global data on international trade and soil-P reserves and deficits from 1970 to 2017, we demonstrate that the contribution of trade to global soil-P deficits increased from 7% in 1970 to 18% in 2017, with 54% of this impact driven by non-food consumption. Over these 48 years, developing regions exported a net of 5.8 Mt P through agricultural trade, resulting in a net increase of 13 Mt soil-P deficits. These deficits are primarily concentrated in regions with low soil-P reserves, such as sub-Saharan Africa, Latin America and Southeast Asia, thereby heightening the risks of soil-P depletion in these areas and amplifying long-term concerns about food security. This insight underscores the imperative for a broader perspective on food security—prioritizing national soil productivity rather than merely boosting the availability of food in the global market when shaping global trade policies.