Fig. 2.
Total N input to China in 2050 under different scenarios. Industry nonimproved represents a case in which industrial N use and NOx from fossil fuels (NOx-FF) remain the same as the BAU across all of the scenarios, and industry improved represents improvement of industrial N use and NOx-FF to levels that have been reached in developed economies elsewhere, for all scenarios. Diet (S1) retains the animal food share of the human diet at 40%; NUE (S2) increases the NUEs of cropland, livestock, and grassland from 40%, 15%, and 6% at present to 60%, 20%, and 10%, respectively; Rec (S3) increases the recycling rates of N from livestock and humans to cropland from 43% and 23% to 80% and 50%, respectively; and All (S4) combines Rec, Diet, and NUE. Units are in Tg N⋅yr−1.