Overview
- University of Copenhagen researchers report the first observation of non-cyanobacterial diazotrophs beneath central Arctic sea ice in Communications Earth & Environment.
- Field campaigns aboard the RV Polarstern in 2021–2022 sampled 13 locations and recorded the highest nitrogen-fixation rates at ice edges.
- Under-ice microbes carry genes for nitrogen fixation, though direct in situ nitrogen-fixing activity by these organisms has not yet been demonstrated.
- The results indicate Arctic nitrogen inputs and potential algal production may be underestimated, while net effects on carbon uptake remain uncertain.
- The team urges modelers to include Arctic nitrogen fixation in projections as sea-ice loss changes habitat conditions for these microbes.