The asymmetric impacts of international agricultural trade on water use scarcity, inequality and inequity

Freshwater is closely interconnected with multiple sustainable development goals (SDGs). Virtual water transfer associated with agricultural trade may help to mitigate water scarcity (SDG6). However, the resulting impacts on water scarcity distribution among income groups (SDG1) and subsequent effects on water use inequality and inequity (SDG10) remain largely unclear. Here we develop an integrated framework to reveal the asymmetric impacts of international agricultural trade on water use scarcity, inequality and inequity between and within developing and developed countries. We find that although agricultural trade generally relieves water scarcity globally, it disproportionately benefits the rich and widens both the water scarcity and inequity gap between the poor and the rich. Notably, in developing countries, the population (35%) suffering from both increased water scarcity and inequity are the poorest group (per capita income is 16% lower than average), whereas the relatively poor (13% population) in developed countries often simultaneously benefit from decreased water scarcity and reduced inequity synergies. Our results thereby highlight striking asymmetric and generally more favourable trade-induced water impacts for developed countries, urging future water and trade policies striving for a better balance across multiple critical SDGs and achieving sustainable development for all.