International food and feed trade and nutrient cycling and balances– exploring relationships at country level

Summary

International trade of food and feed has greatly increased over time, and thereby the transfer of nutrients between countries, notably nitrogen (N) and phosphorus (P). This study aimed to increase the understanding of the quantitative effects of the trade of food and feed on nutrient cycling and nutrient use efficiencies of food systems in food and feed importing countries and exporting countries. Results indicate that the trade of food and feed was related to population and livestock densities, GDP and availability of resources. The trade influenced nutrient balances, nutrient use efficiency and nutrient circularity in importing and exporting countries differently. Also, P input and output circularity indices and their relationships with P balances and P use efficiencies of food systems were different in importing and exporting countries. These insights have consequences for nutrient management and for developing more sustainable food systems at national and global levels.