Global food crop redistribution reduces water footprint without compromising species diversity

Abstract

Food crop yield and species diversity are critical for global population growth, undernourishment, and environmental burden. Crop redistribution is a practical solution to the sustainable intensification of agricultural systems by replacing existing crops with more suitable ones. Here we test this redistribution theory and its impacts on species diversity using six decades of data on the annual world production of 137 food crop products and their average water footprint (WFP). We find the global food crop effective species diversity had an increasing trend from 21 to 27 in recent six decades. Then, we develop a nutrient water footprint productivity index (WFPPI) to optimize crop distribution. Large calorie (+14%), mineral (+25%), and vitamin (+26%) production increases are possible from reshaping the global distribution of 100 crops within the current total WFP and area harvested. Wheat and paddy rice area can reduce by 31% and 34%, respectively, while increasing maize and soybean area by 18% and 40%, respectively. The global redistribution could feed an additional 866 million people while supplying 37% more than the caloric demand for the projected biofuel growth between 2020 and 2030 in the Net Zero Scenario. Such an optimization process does not entail a loss of crop species diversity. With a change of no more than 5%, the stability of the total area harvested for the four largest crops (wheat, maize, paddy rice, and soybeans) is critical for both production and species diversity of all crops. Our results suggest that global crop redistribution provides a promising solution to sustainable production.