Historical nitrogen fertilizers use in China from 1952 to 2018
- 1Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing, China 210044
- 2Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China
- 3School of Geographical Sciences, Nanjing University of Information Science & Technology, Nanjing, China
- 4Department of Infrastructure Engineering, University of Melbourne, Parkville, Melbourne, Australia
- 5Department of Hydraulic Engineering, Tsinghua University, Beijing, China
Abstract. China ranks the highest position on the nitrogen (N) fertilizers consumption in the world. Although the N fertilizers use has greatly contributed to the China’s food production, this has also caused unprecedented alteration in the biogeochemical cycles and endangered terrestrial and aquatic ecosystems. Existing use of N fertilizers in China as shown by digital maps are usually coarse in resolution, and intermittently covered with biasedly gridded dataset. Here, we have reconstructed a historical, annual N fertilizers use dataset in China at 5 km × 5 km resolution covering the period of 1952 to 2018 by integrating improved cropland maps. Results showed that the most of the N input was directly applied as N-only fertilizer, while the contribution from compound fertilizers ranged between 16 % and 24 % since 1980. The national total N fertilizers input increased from 0.06 Tg N yr-1 (0.05 g N m-2 yr-1) in 1952 to 31.15 Tg N yr-1 (18.83 g N m-2 yr-1) in 2014, then decreased to 28.31 Tg N yr-1 (17.06 g N m-2 yr-1) in 2018. Despite the total N input decreased by 9.1 % (2.84 Tg N yr-1) from 2014 to 2018, the N input from compound fertilizers increased by 6 % (0.43 Tg N yr-1) during the corresponding period. The previous FAO-data-based N fertilizer products in China overestimated the N use in low, but underestimated in high cropland coverage areas. However, our newly reconstructed data have not only corrected the existing biases and improved the spatial distribution but also showed vegetable and other crops (orchards), but not grain crops, are the most intensively fertilized crops in China, implying the importance of quantifying greenhouse gas (GHG) emissions from these croplands. We argue that the reconstructed, spatially-explicit N fertilizers use data in this study are expected to contribute to better understanding in biogeochemical cycles including the simulations of GHG emission and food production in China. The cropland dataset is available via an open-data repository (https://doi.org/10.6084/m9.figshare.20402490.v1) (Yu, 2022).
Zhen Yu et al.
Zhen Yu et al.
Nitrogen fertilizer use in China from 1952 to 2018 https://doi.org/10.6084/m9.figshare.20402490.v1
Zhen Yu et al.
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