Significant contributions of combustion-related sources to ammonia emissions

• Published in: Nature communications Vol. 13; no. 1; pp. 7710 - 10
• Main Authors: Chen, Zhi-Li, Song, Wei, Hu, Chao-Chen, Liu, Xue-Jun, Chen, Guan-Yi, Walters, Wendell W., Michalski, Greg, Liu, Cong-Qiang, Fowler, David, Liu, Xue-Yan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13.12.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 704/172/169/209; 704/172/169/824; 704/47/4112; Air Pollutants - analysis; Air Pollution; Air quality; Ammonia; Ammonia - analysis; Ammonium; Biomass burning; China; Combustion; Ecological effects; Ecosystem; Emission analysis; Emission inventories; Emissions; Environmental Monitoring - methods; Fertilizers; Fossil fuels; Humanities and Social Sciences; Isotopes; multidisciplinary; Nitrogen; Nitrogen - analysis; Nitrogen isotopes; Science; Science (multidisciplinary); Systematics; Volatilization; China
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-35381-4

Atmospheric ammonia (NH 3 ) and ammonium (NH 4 + ) can substantially influence air quality, ecosystems, and climate. NH 3 volatilization from fertilizers and wastes (v-NH 3 ) has long been assumed to be the primary NH 3 source, but the contribution of combustion-related NH 3 (c-NH 3 , mainly fossil fuels and biomass burning) remains unconstrained. Here, we collated nitrogen isotopes of atmospheric NH 3 and NH 4 + and established a robust method to differentiate v-NH 3 and c-NH 3 . We found that the relative contribution of the c-NH 3 in the total NH 3 emissions reached up to 40 ± 21% (6.6 ± 3.4 Tg N yr −1 ), 49 ± 16% (2.8 ± 0.9 Tg N yr −1 ), and 44 ± 19% (2.8 ± 1.3 Tg N yr −1 ) in East Asia, North America, and Europe, respectively, though its fractions and amounts in these regions generally decreased over the past decades. Given its importance, c-NH 3 emission should be considered in making emission inventories, dispersion modeling, mitigation strategies, budgeting deposition fluxes, and evaluating the ecological effects of atmospheric NH 3 loading. By integrating nitrogen isotope systematics of ammonia emissions and transformations in the atmosphere, this study quantified the combustion-related ammonia emission and uncovered its importance for mitigating strategies of ammonia pollution.