Marine ecosystem shifts with deglacial sea-ice loss inferred from ancient DNA shotgun sequencing

• Published in: Nature Communications
• Main Authors: Zimmermann, Heike H., Stoof-Leichsenring, Kathleen R., Dinkel, Viktor, Harms, Lars, Schulte, Luise, Hütt, Marc-Thorsten, Nürnberg, Dirk, Tiedemann, Ralf, Herzschuh, Ulrike
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Research 2023
• Subjects: Bering Sea; Pacific; Kamchatka; Sea ice; Copepods
• Online Access: https://oceanrep.geomar.de/id/eprint/58280/; https://oceanrep.geomar.de/id/eprint/58280/1/s41467-023-36845-x.pdf; https://oceanrep.geomar.de/id/eprint/58280/2/41467_2023_36845_MOESM1_ESM.pdf; https://oceanrep.geomar.de/id/eprint/58280/3/41467_2023_36845_MOESM4_ESM.xlsx; https://oceanrep.geomar.de/id/eprint/58280/4/41467_2023_36845_MOESM6_ESM.xlsx; https://doi.org/10.1038/s41467-023-36845-x

Sea ice is a key factor for the functioning and services provided by polar marine ecosystems. However, ecosystem responses to sea-ice loss are largely unknown because time-series data are lacking. Here, we use shotgun metagenomics of marine sedimentary ancient DNA off Kamchatka (Western Bering Sea) covering the last ~20,000 years. We traced shifts from a sea ice-adapted late-glacial ecosystem, characterized by diatoms, copepods, and codfish to an ice-free Holocene characterized by cyanobacteria, salmon, and herring. By providing information about marine ecosystem dynamics across a broad taxonomic spectrum, our data show that ancient DNA will be an important new tool in identifying long-term ecosystem responses to climate transitions for improvements of ocean and cryosphere risk assessments. We conclude that continuing sea-ice decline on the northern Bering Sea shelf might impact on carbon export and disrupt benthic food supply and could allow for a northward expansion of salmon and Pacific herring.