Microbial Fe(III) Reduction as a Potential Iron Source from Holocene Sediments Beneath Larsen Ice Shelf

Authors

Jaewoo Jung, Yonsei University
Kyu-Cheul Yoo, Korea Polar Research Institute
Brad E. Rosenheim, University of South FloridaFollow
Tim M. Conway, University of South FloridaFollow
Jae Il Lee, Korea Polar Research Institute
Ho Il Yoon, Korea Polar Research Institute
Chung Yeon Hwang, Korea Polar Research Institute
Kiho Yang, Yonsei University
Christina Subt, University of South Florida
Jinwook Kim, Yonsei University

Document Type

Article

Publication Date

2019

Keywords

Element cycles, Geochemistry, Marine chemistry

Digital Object Identifier (DOI)

https://doi.org/10.1038/s41467-019-13741-x

Abstract

Recent recession of the Larsen Ice Shelf C has revealed microbial alterations of illite in marine sediments, a process typically thought to occur during low-grade metamorphism. In situ breakdown of illite provides a previously-unobserved pathway for the release of dissolved Fe²⁺ to porewaters, thus enhancing clay-rich Antarctic sub-ice shelf sediments as an important source of Fe to Fe-limited surface Southern Ocean waters during ice shelf retreat after the Last Glacial Maximum. When sediments are underneath the ice shelf, Fe²⁺ from microbial reductive dissolution of illite/Fe-oxides may be exported to the water column. However, the initiation of an oxygenated, bioturbated sediment under receding ice shelves may oxidize Fe within surface porewaters, decreasing dissolved Fe²⁺ export to the ocean. Thus, we identify another ice-sheet feedback intimately tied to iron biogeochemistry during climate transitions. Further constraints on the geographical extent of this process will impact our understanding of iron-carbon feedbacks during major deglaciations.

Rights Information

This work is licensed under a Creative Commons Attribution 4.0 License.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

Nature Communications, v. 10, art. 5786

Scholar Commons Citation

Jung, Jaewoo; Yoo, Kyu-Cheul; Rosenheim, Brad E.; Conway, Tim M.; Lee, Jae Il; Yoon, Ho Il; Hwang, Chung Yeon; Yang, Kiho; Subt, Christina; and Kim, Jinwook, "Microbial Fe(III) Reduction as a Potential Iron Source from Holocene Sediments Beneath Larsen Ice Shelf" (2019). Marine Science Faculty Publications. 2418.
https://digitalcommons.usf.edu/msc_facpub/2418