A global database of nitrogen fixation rates across inland and coastal waters.

Authors: FULWEILER, ROBINSON - Boston University; BERBERICH, MEGAN - Michigan Technological University; RINEHART, SHELBY - Drexel University; Taylor, Jason; KELLY, MICHELLE - Michigan Technological University; RAY, NICHOLAS - University Of Delaware; OCZKOWSKI, AUTUMN - Us Environmental Protection Agency (EPA); BALINT, SAWYER - Boston University; GEISSER, ALEXANDER - Boston University; BENAVIDES, MAR - Aix-Marseille University; CHURCH, MATTHEW - University Of Montana; LOEKS, BRIANNA - University Of Minnesota; NEWELL, SILVIA - University Of Michigan; OLOFSSON, MALIN - Swedish University Of Agricultural Sciences; OPPONG, JIMMY - Charles University, Czech Republic; ROLEY, SARAH - Washington State University; VIZZA, CARMELA - Hawaii Pacific University; WILSON, SAM - Newcastle University; GROFMMAN, PETER - Cary Institute Of Ecosystem Studies; SCOTT, JEFERSON - Baylor University; MARCARELLI, AMY - Michigan Technological University

Submitted to: Limnology and Oceanography Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/2/2025
Publication Date: 1/24/2025
Citation: Fulweiler, R.W., Berberich, M., Rinehart, S., Taylor, J.M., Kelly, M.C., Ray, N.E., Oczkowski, A., Balint, S., Geisser, A., Benavides, M., Church, M., Loeks, B., Newell, S., Olofsson, M., Oppong, J., Roley, S., Vizza, C., Wilson, S., Grofmman, P., Scott, J.T., Marcarelli, A. 2025. A global database of nitrogen fixation rates across inland and coastal waters.. Limnology and Oceanography Letters. https://doi.org/10.1002/lol2.10459.
DOI: https://doi.org/10.1002/lol2.10459

Interpretive Summary: Understanding global contributions of different sources of nitrogen is important information that drives decisions for wise management of excess nitrogen in our environment. Biological nitrogen fixation is the primary natural pathway for nitrogen to become available to plants and animals on Earth. Researchers have a good understanding of the contribution of biologically fixed nitrogen from land and ocean systems to global nitrogen availability but no comprehensive examinations have been done to estimate the contribution from inland (lakes, rivers, wetlands) and coastal aquatic ecosystems. Researchers used a systematic approach to extract information from published literature and develop a database of rates from these habitats across the globe. This database will be used in a future publication to estimate the contribution of biological nitrogen fixation in inland and coastal aquatic ecosystems to the global nitrogen pool. The database is publicly available for future research on this important process regulating nutrient availability on Earth.

Technical Abstract: Biological nitrogen fixation is the conversion of dinitrogen (N2) gas into bioavailable nitrogen by microorganisms with consequences for primary production, ecosystem function, and global climate. Here we present a compiled dataset of 4793 nitrogen fixation (N2-fixation) rates measured in the water column and benthos of inland and coastal systems via the acetylene reduction assay, 15N2 labeling, or N2/Ar technique. While the data are distributed across 7 continents, most observations (88%) are from the northern hemisphere. 15N2 labeling accounted for 67% of water column measurements, while the acetylene reduction assay accounted for 81% of benthic N2-fixation observations. Dataset median area-, volume-, and mass-normalized N2-fixation rates are 7.1 umol N2-N m-2 h-1, 2.3 x 10-4 umol N2-N L-1 h-1, and 4.8 x 10-4 umol N2-N g-1 h-1, respectively. This dataset will facilitate future efforts to study and scale N2-fixation contributions across inland and coastal aquatic environments.