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6. Back Cover

Author

Arnold, Brian C.

Published
2022

7. Colophon

Author

Arnold, Brian C.

Published
2022

10. Index

Author

Arnold, Brian C.

Published
2022

30. Limnological conditions in Subglacial Lake Vostok, Antarctica

Author

Christner, BC, Royston-Bishop, G, Foreman, CF, Arnold, BR, Tranter, Martyn, Welch, KA, Lyons, WB, Tsapin, AI, and Priscu, JC

Abstract

Subglacial Lake Vostok is located ~4 km beneath the surface of the East Antarctic Ice Sheet and has been isolated from the atmosphere for >15 million yr. Concerns for environmental protection have prevented direct sampling of the lake water thus far. However, an ice core has been retrieved from above the lake in which the bottom ,85 m represents lake water that has accreted (i.e., frozen) to the bottom of the ice sheet. We measured selected constituents within the accretion ice core to predict geomicrobiological conditions within the surface waters of the lake. Bacterial density is two- to sevenfold higher in accretion ice than the overlying glacial ice, implying that Lake Vostok is a source of bacterial carbon beneath the ice sheet. Phylogenetic analysis of amplified small subunit ribosomal ribonucleic acid (rRNA) gene sequences in accretion ice formed over a deep portion of the lake revealed phylotypes that classify within the b-, c-, and d-Proteobacteria. Cellular, major ion, and dissolved organic carbon levels all decreased with depth in the accretion ice (depth is a proxy for increasing distance from the shoreline), implying a greater potential for biological activity in the shallow shoreline waters of the lake. Although the exact nature of the biology within Lake Vostok awaits direct sampling of the lake water, our data from the accretion ice support the working hypothesis that a sustained microbial ecosystem is present in this subglacial lake environment, despite high pressure, constant cold, low nutrient input, potentially high oxygen concentrations, and an absence of sunlight.

Published
2006

31. Contributors

Author

Arnold, Bruce Makoto, Tunç, Tanfer Emin, and Chong, Raymond Douglas

Published
2018

33. Notes

Author

Arnold, Bruce Makoto, Tunç, Tanfer Emin, and Chong, Raymond Douglas

Published
2018

34. Index

Author

Arnold, Bruce Makoto, Tunç, Tanfer Emin, and Chong, Raymond Douglas

Published
2018

48. Preface

Author

Arnold, Bruce Makoto, Tunç, Tanfer Emin, and Chong, Raymond Douglas

Published
2018

50. Foreword

Author

Arnold, Bruce Makoto, Tunç, Tanfer Emin, and Chong, Raymond Douglas

Published
2018

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