Rethinking agricultural trade relationships in an era of globalization

Agricultural trade plays an important role in global food security and resource sustainability. Global food commodities trade is worth more than US$520 billion per year, could feed approximately two billion people, uses about 13% of worldwide cropland and pasture, and has geographically concentrated irrigation water demands. However, researchers rarely compare these monetary, nutritional, and resource metrics, which limits our ability to holistically evaluate the drivers and implications of trade. We found that each metric suggests distinct conclusions about the geography of globalized agriculture. For example, traded animal products have a disproportionate influence according to value-based and embodied pasture metrics. Traded wheat, soybean, and maize contain the most calories, use the most cropland, and strongly influence irrigation water consumption. We typify engagement in trade by assessing how countries allocate cropland to domestic versus foreign demand. Simultaneous consideration of multiple metrics could enhance decisionmaking surrounding trade by capturing the complex biophysical and economic context of agricultural globalization.