Historical nitrogen fertilizer use in China from 1952 to 2018

Abstract. China ranks in the highest position for nitrogen (N) fertilizer consumption world. Although N use has greatly contributed to China's food production, this also caused an unprecedented alteration biogeochemical cycles and endangered terrestrial aquatic ecosystems. Existing of fertilizers China, as shown by digital maps, is usually coarse resolution intermittently covered with a biased gridded dataset. Here, we have reconstructed historical, annual dataset resampled it 5 km×5 km resolution, covering period from 1952 2018 integrating improved cropland maps. Results showed that most input was directly applied N-only fertilizer, while contribution compound ranged between 16 % 24 since 1980. The national total increased 0.06 Tg yr−1 (0.05 g m−2 yr−1) 31.15 (18.83 2014 then decreased 28.31 (17.06 2018. Despite decreasing 9.1 (2.84 2018, 6 (0.43 during corresponding period. previous Food Agriculture Organization (FAO) data-based products overestimated low coverage areas but underestimated high areas. However, our newly data not only corrected existing biases spatial distribution vegetable other crops (e.g., orchards), grain crops, are intensively fertilized implying importance quantifying greenhouse gas (GHG) emissions these croplands. We argue reconstructed, spatially explicit study expected contribute better understanding cycles, including simulations GHG production China. crop-specific datasets available via open repository (https://doi.org/10.6084/m9.figshare.21371469.v1; Yu, 2022).