Reactive nitrogen losses from China's food system for the shared socioeconomic pathways (SSPs)

Food production in China has been changing fast as a result of socio-economic development. This resulted in an increased use of nitrogen (N) in food production, and also to increased reactive nitrogen (Nr) losses to the environment, causing nitrogen pollution. Our study is the first to quantify future Nr losses from China's food system for the Shared Socio-economic Pathways (SSPs). We show that Nr losses differ largely among SSPs. We first qualitatively described the five SSP storylines for China with a focus on food production and consumption. Next, we interpreted these SSP scenarios quantitatively for 2030 and 2050, using the NUFER (NUtrient Flows in Food chains, Environment and Resources use) model to project the Nr losses from China's food system. The results indicate that Nr losses from future food system in China are relatively low for SSP1 and SSP2, and relatively high for SSP3 and SSP4. In SSP5 Nr losses from China's food system are projected to be slightly lower than the level of today.