The Watson River drains a portion of the SW Greenland ice sheet, transporting microbial communities from subglacial environments to a delta at the head of Søndre Strømfjord. This study investigates the potential activity and community shifts of glacial microbiota deposited and buried under layers of sediments within the river delta. A long-term (12-month) incubation experiment was established using Watson River delta sediment under anaerobic conditions, with and without CO2/H2 enrichment. Within CO2/H2-amended incubations, sulphate depletion and a shift in the microbial community to a 52% predominance of Desulfosporosinus meridiei by day 371 provides evidence for sulphate reduction. We found evidence of methanogenesis in CO2/H2-amended incubations within the first 5 months, with production rates of ~4 pmol g-1 d-1, which was likely performed by methanogenic Methanomicrobiales- and Methanosarcinales-related organisms. Later, a reduction in methane was observed to be paired with the depletion of sulphate, and we hypothesise that sulphate reduction out competed hydrogenotrophic methanogenesis. The structure and diversity of the original CO2/H2-amended incubation communities changed dramatically with a major shift in predominant community members and a decline in diversity and cell abundance. These results highlight the need for further investigations into the fate of subglacial microbiota within downstream environments.

Center for Permafrost University of Copenhagen Øster Voldgade 10 DK 1350 Copenhagen Denmark

Department of Ecology Faculty of Science Charles University Viničná 7 128 43 Prague Czech Republic

Department of Environmental Science Aarhus University Frederiksborgvej 399 DK 4000 Roskilde Denmark

Department of Geochemistry Geological Survey of Denmark and Greenland Øster Voldgade 10 DK 1350 Copenhagen Denmark

Institute of Biological Environmental and Rural Sciences Aberystwyth University Penglais Aberystwyth SY23 3FL UK

Zobrazit více v PubMed

Hasholt B, Mikkelsen AB, Nielsen MH, Larsen MAD. Observations of runoff and sediment and dissolved loads from the Greenland ice sheet at Kangerlussuaq, West Greenland, 2007 to 2010. Z Geomorphol, Supplementary Issue. 2012;57:3–27. doi: 10.1127/0372-8854/2012/S-00121. DOI

Cameron KA, Stibal M, Hawkings JR, Mikkelsen AB, Telling J, Kohler TJ, Gözdereliler E, Zarsky JD, Wadham JL, Jacobsen CS. Meltwater export of prokaryotic cells from the Greenland ice sheet. Environ. Microbiol. 2016 PubMed

Boyd ES, Skidmore M, Mitchell AC, Bakermans C, Peters JW. Methanogenesis in subglacial sediments. Environ. Microbiol. Rep. 2010;2:685–692. doi: 10.1111/j.1758-2229.2010.00162.x. PubMed DOI

Skidmore ML, Foght JM, Sharp MJ. Microbial life beneath a high Arctic glacier. Appl. Environ. Microbiol. 2000;66:3214–3220. doi: 10.1128/AEM.66.8.3214-3220.2000. PubMed DOI PMC

Dieser M, Broemsen ELJE, Cameron KA, King GM, Achberger A, Choquette K, Hagedorn B, Sletten R, Junge K, Christner BC. Molecular and biogeochemical evidence for methane cycling beneath the western margin of the Greenland ice sheet. ISME J. 2014;8:2305–2316. doi: 10.1038/ismej.2014.59. PubMed DOI PMC

Wadham JL, Arndt S, Tulaczyk S, Stibal M, Tranter M, Telling J, Lis GP, Lawson E, Ridgwell A, Dubnick A, Sharp MJ, Anesio AM, Butler CEH. Potential methane reservoirs beneath Antarctica. Nature. 2012;488:633–637. doi: 10.1038/nature11374. PubMed DOI

Stibal M, Wadham JL, Lis GP, Telling J, Pancost RD, Dubnick A, Sharp MJ, Lawson EC, Butler CE, Hasan F. Methanogenic potential of Arctic and Antarctic subglacial environments with contrasting organic carbon sources. Glob Change Biol. 2012;18:3332–3345. doi: 10.1111/j.1365-2486.2012.02763.x. DOI

Wadham JL, Bottrell S, Tranter M, Raiswell R. Stable isotope evidence for microbial sulphate reduction at the bed of a polythermal high Arctic glacier. Earth Planet. Sci. Lett. 2004;219:341–355. doi: 10.1016/S0012-821X(03)00683-6. DOI

Pester M, Brambilla E, Alazard D, Rattei T, Weinmaier T, Han J, Lucas S, Lapidus A, Cheng J-F, Goodwin L, Pitluck S, Peters L, Ovchinnikova G, Teshima H, Detter JC, Han CS, Tapia R, Land ML, Hauser L, Kyrpides NC, Ivanova NN, Pagani I, Huntmann M, Wei C-L, Davenport KW, Daligault H, Chain PSG, Chen A, Mavromatis K, Markowitz V, Szeto E, Mikhailova N, Pati A, Wagner M, Woyke T, Ollivier B, Klenk H-P, Spring S, Loy A. Complete genome sequences of Desulfosporosinus orientis DSM765(T), Desulfosporosinus youngiae DSM17734(T), Desulfosporosinus meridiei DSM13257(T), and Desulfosporosinus acidiphilus DSM22704(T) J. Bacteriol. 2012;194:6300–6301. doi: 10.1128/JB.01392-12. PubMed DOI PMC

Lloyd KG, Alperin MJ, Teske A. Environmental evidence for net methane production and oxidation in putative ANaerobic MEthanotrophic (ANME) archaea. Environ. Microbiol. 2011;13:2548–2564. doi: 10.1111/j.1462-2920.2011.02526.x. PubMed DOI

Stibal M, Hasan F, Wadham JL, Sharp MJ, Anesio AM. Prokaryotic diversity in sediments beneath two polar glaciers with contrasting organic carbon substrates. Extremophiles. 2012;16:255–265. doi: 10.1007/s00792-011-0426-8. PubMed DOI

Hamilton TL, Peters JW, Skidmore ML, Boyd ES. Molecular evidence for an active endogenous microbiome beneath glacial ice. ISME J. 2013;7:1402–1412. doi: 10.1038/ismej.2013.31. PubMed DOI PMC

Oremland RS, Polcin S. Methanogenesis and sulfate reduction: competitive and noncompetitive substrates in estuarine sediments. Appl. Environ. Microbiol. 1982;44:1270–1276. PubMed PMC

Boetius A, Ravenschlag K, Schubert CJ, Rickert D, Widdel F, Gieseke A, Amann R, Jørgensen BB, Witte U, Pfannkuche O. A marine microbial consortium apparently mediating anaerobic oxidation of methane. Nature. 2000;407:623–626. doi: 10.1038/35036572. PubMed DOI

Pernthaler A, Dekas AE, Brown CT, Goffredi SK, Embaye T, Orphan VJ. Diverse syntrophic partnerships from deep-sea methane vents revealed by direct cell capture and metagenomics. Proc. Natl. Acad. Sci. U. S. A. 2008;105:7052–7057. doi: 10.1073/pnas.0711303105. PubMed DOI PMC

Meulepas RJ, Jagersma CG, Zhang Y, Petrillo M, Cai H, Buisman CJ, Stams AJ, Lens PN. Trace methane oxidation and the methane dependency of sulfate reduction in anaerobic granular sludge. FEMS Microbiol. Ecol. 2010;72:261–271. doi: 10.1111/j.1574-6941.2010.00849.x. PubMed DOI

Fettweis X, Franco B, Tedesco M, Van Angelen JH, Lenaerts JTM, Van den Broeke MR, Gallée H. Estimating Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR. Cryosphere. 2012;7:3101–3147. doi: 10.5194/tcd-6-3101-2012. DOI

Methylotrophic Communities Associated with a Greenland Ice Sheet Methane Release Hotspot

Catchment characteristics and seasonality control the composition of microbial assemblages exported from three outlet glaciers of the Greenland Ice Sheet