OPP-PRF: Benthic Iron Fluxes and Cycling in the Amundsen Sea

The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through CryoConnect.org.

This project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment Fe cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface.

These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the “Accelerating Thwaites Ecosystem Impacts for the Southern Ocean” (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system.

This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond.