Managing nitrogen, water and carbon flows and their interactions for circularity in agrifood systems - a case study in Quzhou, China

Summary

Linear agrifood systems cause substantial losses of nitrogen (N), carbon (C) and water to the environment. Addressing these challenges requires closing the loops of N, C, and water within the system, encompassing crop and livestock production, food processing, household consumption and waste management. Promoting circularity necessitates selecting the most relevant spatial scale. This thesis aimed to explore circularity options for N, C, and water in agrifood systems at the county scale.

The results demonstrate the possibility of transitioning towards a N-circular, water-secure, and C-neutral agrifood system. The recycling of organic waste is one of the most effective and feasible measures to move towards circularity. Less recharge flows, due to less and more efficient agricultural water use, would result in lower discharge of N pollutants. synergies in N circularity and C neutrality are also identified. Balancing circularity and agricultural trade to achieve sustainability at different scales will be the greatest challenge.