Data on nitrogen input, surplus and nitrogen use efficiency are provided globally, and for USA, European Union, China, Brazil and South Asia (i.e. India, Nepal, Bangladesh and Pakistan) for 1995 to 2013. Nitrogen input (in the file ninput_1995_2013.csv) is separated into synthetic fertiliser (FERT), manure (MANURE), biological nitrogen fixation (BNF), and NOx deposition from non-agricultural sources (NOx). These N-inputs are for the whole agricultural system, including crops and grassland. Also included is N-surplus (SURPLUS) for cropping systems, which is calculated as the difference between the total N-input and the N removed through harvest. NUE (in the file nue_1995_2013.csv) is N in harvest relative to the total N-input. Synthetic fertilizer application is based on the FAOSTAT dataset (http://www.fao.org/home/en/) with several inputs from the International Fertilizer Association (https://www.fertilizer.org/). Total animal excretion is calculated using the FAOSTAT livestock inventory and dynamic excretion factors, biological N fixation is calculated from crop productivities (Anglade et al., 2015) and atmospheric deposition was from Dentener et al. (2006). Grassland nitrogen fixation was based on the grassland production estimated following Lassaletta et al. (2016). N in harvested crops is based on crop productivity and N content of 177 crops, utilizing data from the FAOSTAT database.

{"references": ["Anglade, J., Billen, G., & Garnier, J., Relationships for estimating N2 fixation in legumes: incidence for N balance of legume-based cropping systems in Europe. Ecosphere 6, 37 (2015)", "Dentener, F. et al. Nitrogen and sulfur deposition on regional and global scales: A multimodel evaluation. Global Biogeochem. Cycles, 20(4) (2006)", "Lassaletta, L. et al. Nitrogen use in the global food system: Past trends and future trajectories of agronomic performance, pollution, trade, and dietary demand. Environ. Res. Lett. 11. (2016)"]}