Wang, ShuoZhi, WeiLi, ShengjieLyu, TaoJi, Guodong2025-03-202025-03-202025-02-01Wang S, Zhi W, Li S, et al., (2025) Sustainable management of riverine N2O emission baselines. National Science Review, Volume 12, Issue 2, February 2025, Article number nwae4582095-5138https://doi.org/10.1093/nsr/nwae458https://dspace.lib.cranfield.ac.uk/handle/1826/23625The riverine N2O fluxes are assumed to linearly increase with nitrate loading. However, this linear relationship with a uniform EF5r is poorly constrained, which impedes the N2O estimation and mitigation. Our meta-analysis discovered a universal N2O emission baseline (EF5r = k/[NO3−], k = 0.02) for natural rivers. Anthropogenic impacts caused an overall increase in baselines and the emergence of hotspots, which constitute two typical patterns of anthropogenic sources. The k values of agricultural and urban rivers increased to 0.09 and 0.05, respectively, with 11% and 14% of points becoming N2O hotspots. Priority control of organic and NH4+ pollution could eliminate hotspots and reduce emissions by 51.6% and 63.7%, respectively. Further restoration of baseline emissions on nitrate removal is a long-term challenge considering population growth and declining unit benefits (ΔN-N2O/N-NO3−). The discovery of EF lines emphasized the importance of targeting hotspots and managing baseline emissions sustainably to balance social and environmental benefits.Electronic-eCollectionenAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/nitrous oxideemission factorhotspotssustainablegreenhouse gases41 Environmental Sciences4104 Environmental ManagementArticle2053-714X561001nwae458122