The analysis showed that nutrients and organic matter influence the isotope compositions recorded in sea ice. By combining hydrographic measurements with sea-ice data, the team estimated how much particulate organic carbon the ice supplies to surrounding waters.

The estimate is notable: the carbon supplied from sea ice was equivalent to 14.7 percent of phytoplankton production near the ice edge. That figure points to sea-ice derived material as a meaningful contributor to the base of the Antarctic food web, complementing open-water plankton growth.

Because the findings rest on field collections and isotope measurements from the Southern Ocean, they provide a quantitative basis for assessing the role of sea-ice derived materials in Antarctic ecosystems. The study highlights the importance of ice-associated organic matter for carbon cycling in polar waters.

Subject of Research: Biogeochemical controls on particulate organic matter in Southern Ocean sea ice and its carbon supply to Antarctic ecosystems

Article Title: Biogeochemical controls on the concentrations and stable isotope compositions of sea-ice particulate organic matters in the Southern Ocean

Article References: Takahashi, K. D., Makabe, R., Sano, M., Nakata, K., Kimura, N., Nomura, D., Yamamoto-Kawai, M., Matsuda, R., Nojiro, N., Ito, M., Takao, S., Horimoto-Miyazaki, N., Tachibana, A., Kurosawa, N., Tamura, T., Komatsu, M., Ohshima, K. I., Mizobata, K., Aoki, S., & Moteki, M. (2026). Biogeochemical controls on the concentrations and stable isotope compositions of sea-ice particulate organic matters in the Southern Ocean. Biogeosciences, 23(20), 7505-7522. https://doi.org/10.5194/bg-23-7505-2026

Image Credits: AI Generated

DOI: 10.5194/bg-23-7505-2026

Keywords: Southern Ocean, sea ice, particulate organic carbon, stable isotopes, phytoplankton production, Antarctic ecosystems, biogeochemistry, ice edge, carbon cycling, nutrients, Biogeochemical, controls