Storage and export of microbial biomass across the western Greenland Ice Sheet

Irvine-Fynn, T.D.L. et al. (2021) Storage and export of microbial biomass across the western Greenland Ice Sheet. Nature Communications, 12, 3960. (doi: 10.1038/s41467-021-24040-9) (PMID:34172727) (PMCID:PMC8233322)

Abstract

The Greenland Ice Sheet harbours a wealth of microbial life, yet the total biomass stored or exported from its surface to downstream environments is unconstrained. Here, we quantify microbial abundance and cellular biomass flux within the near-surface weathering crust photic zone of the western sector of the ice sheet. Using groundwater techniques, we demonstrate that interstitial water flow is slow (~10−2 m d−1), while flow cytometry enumeration reveals this pathway delivers 5 × 108 cells m−2 d−1 to supraglacial streams, equivalent to a carbon flux up to 250 g km−2 d−1. We infer that cellular carbon accumulation in the weathering crust exceeds fluvial export, promoting biomass sequestration, enhanced carbon cycling, and biological albedo reduction. We estimate that up to 37 kg km−2 of cellular carbon is flushed from the weathering crust environment of the western Greenland Ice Sheet each summer, providing an appreciable flux to support heterotrophs and methanogenesis at the bed.

• Item Type: Articles
• Additional Information: This research was supported by a Royal Society Grant (RG130314: PRESTIGE, to A.E. and T.D.L.I.-F.). We acknowledge NERC Large Grant (NE/M020991/1 and NE/M021025: Black & Bloom, supporting T.D.L.I.-F., J.M.C. and C.J.W., with recognition of project investigators including M Tranter, AJ Hodson, E Hanna, and M Yallop). T.D.L.I.-F. acknowledges Leverhulme Trust Fellowship RF-2018-584/4. A.E. acknowledges Leverhulme Trust Fellowship RF-2017-652. A.E., T.D.L.I.-F., S.M.E.R. and J.M.C. all recognise NERC Standard Grant (NE/S001034/1: MicroMelt). A.C.M. and A.E. acknowledge support from a National Research Network for Low Carbon Energy and Environment (NRN-LCEE) grant from the Welsh Government and the Higher Education Funding Council for Wales (HEFCW): Geo-Carb-Cymru. J.M.C. recognises the Rolex Awards for Enterprise and National Geographic. K.A.C. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant agreement No. 663830. Financial support was also provided to K.A.C. by the Welsh Government and Higher Education Funding Council for Wales through the Sêr Cymru National Research Network for Low Carbon, Energy and Environment. K.N. was involved through a SNSF Mobility Fellowship Grant (P2FRP2/174888); A.H. acknowledges a research professorship from the Research Council of Norway through its Centres of Excellence scheme (Grant 223259) and an Academy of Finland ArcI visiting fellowship to the University of Oulu. Logistical field support from the Dark Snow Project (www.darksnow.org) led by J.E.B., and a Villum Young Investigator Programme (Grant VKR-023121) and a Czech Science Foundation (Grant: 19-21341 S) held by M.S. are gratefully recognised.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cameron, Dr Karen
• Authors: Irvine-Fynn, T.D.L., Edwards, A., Stevens, I.T., Mitchell, A.C., Bunting, P., Box, J., Cameron, K. A., Cook, J.M., Naegeli, K., Rassner, S.M.E., Ryan, J.C., Stibal, M., Williamson, C.J., and Hubbard, A.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Nature Communications
• Publisher: Nature Research
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Copyright Holders: Copyright © The Author(s) 2021
• First Published: First published in Nature Communications 12:3960
• Publisher Policy: Reproduced under a Creative Commons Licence