Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica

The abundance of liquid water found beneath the Antarctic Ice Sheet (AIS) is thought to provide a suitable habitat for microbial life. However, the thick ice sheet has posed a significant obstacle to accessing this isolated system and as a consequence, little data exists to infer ecosystem processes...

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Main Author: Achberger, Amanda Marie
Format: Text
Language:unknown
Published: LSU Digital Commons 2016
Subjects:
Online Access:https://digitalcommons.lsu.edu/gradschool_dissertations/4453
https://doi.org/10.31390/gradschool_dissertations.4453
https://digitalcommons.lsu.edu/context/gradschool_dissertations/article/5460/viewcontent/Achberger_diss.pdf
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spelling ftlouisianastuir:oai:digitalcommons.lsu.edu:gradschool_dissertations-5460 2023-06-11T04:06:30+02:00 Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica Achberger, Amanda Marie 2016-01-01T08:00:00Z application/pdf https://digitalcommons.lsu.edu/gradschool_dissertations/4453 https://doi.org/10.31390/gradschool_dissertations.4453 https://digitalcommons.lsu.edu/context/gradschool_dissertations/article/5460/viewcontent/Achberger_diss.pdf unknown LSU Digital Commons https://digitalcommons.lsu.edu/gradschool_dissertations/4453 doi:10.31390/gradschool_dissertations.4453 https://digitalcommons.lsu.edu/context/gradschool_dissertations/article/5460/viewcontent/Achberger_diss.pdf LSU Doctoral Dissertations Antarctica Subglacial Lake Microbial Ecology Life Sciences text 2016 ftlouisianastuir https://doi.org/10.31390/gradschool_dissertations.4453 2023-05-28T19:16:37Z The abundance of liquid water found beneath the Antarctic Ice Sheet (AIS) is thought to provide a suitable habitat for microbial life. However, the thick ice sheet has posed a significant obstacle to accessing this isolated system and as a consequence, little data exists to infer ecosystem processes occurring beneath ice sheets. To address this deficit, data generated through 16S rRNA (genes and molecules) and metagenomic sequencing was used to evaluate the diversity and potential metabolic function of communities inhabiting Subglacial Lake Whillans (SLW) and the ocean basin into which it discharges (Whillans Ice Stream grounding zone; WIS-GZ). The analysis of SLW was found to be dominated by bacterial and archaeal species with little evidence for active eukaryotic organisms. The abundance of taxa related to chemolithoautrophic species (e.g., Thiobacillus, Sideroxydans, Nitrosospira, and Candidatus Nitrosoarcheaum) suggested that reduced sulfur, iron, and nitrogen compounds were important in fueling primary production in the permanently dark lake. Consistent with this, genes involved in inorganic carbon fixation, sulfide oxidation, and ammonia oxidation were also identified and taxonomically affiliated with species of Thiobacillus and Nitrosospira. Furthermore, the abundance of sequences related to Methylobacter¬ combined with the detection of methanogenic taxa provided evidence for methane cycling beneath the AIS. Although organic carbon and nutrients generated in SLW are transported to the WIS-GZ and may help support the diverse community found there, the prevalence of chemolithoautotrophic taxa (e.g., Thioprofundum and Thiohalophilus) suggests primary production coupled to the oxidation of reduced sulfur compounds may also provide a source of new fixed carbon to the system. The WIS-GZ community was distinct from those of SLW and the Ross Ice Shelf edge, signifying that it is structured based on the combined influences of input from the subglacial and marine systems. Collectively, these studies show that ... Text Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Ross Ice Shelf West Antarctica Whillans Ice Stream LSU Digital Commons (Louisiana State University) Antarctic The Antarctic West Antarctica Ross Ice Shelf Whillans ENVELOPE(-64.250,-64.250,-84.450,-84.450) Whillans Ice Stream ENVELOPE(-145.000,-145.000,-83.667,-83.667) Dark Lake ENVELOPE(-109.117,-109.117,59.567,59.567)
institution Open Polar
collection LSU Digital Commons (Louisiana State University)
op_collection_id ftlouisianastuir
language unknown
topic Antarctica
Subglacial Lake
Microbial Ecology
Life Sciences
spellingShingle Antarctica
Subglacial Lake
Microbial Ecology
Life Sciences
Achberger, Amanda Marie
Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
topic_facet Antarctica
Subglacial Lake
Microbial Ecology
Life Sciences
description The abundance of liquid water found beneath the Antarctic Ice Sheet (AIS) is thought to provide a suitable habitat for microbial life. However, the thick ice sheet has posed a significant obstacle to accessing this isolated system and as a consequence, little data exists to infer ecosystem processes occurring beneath ice sheets. To address this deficit, data generated through 16S rRNA (genes and molecules) and metagenomic sequencing was used to evaluate the diversity and potential metabolic function of communities inhabiting Subglacial Lake Whillans (SLW) and the ocean basin into which it discharges (Whillans Ice Stream grounding zone; WIS-GZ). The analysis of SLW was found to be dominated by bacterial and archaeal species with little evidence for active eukaryotic organisms. The abundance of taxa related to chemolithoautrophic species (e.g., Thiobacillus, Sideroxydans, Nitrosospira, and Candidatus Nitrosoarcheaum) suggested that reduced sulfur, iron, and nitrogen compounds were important in fueling primary production in the permanently dark lake. Consistent with this, genes involved in inorganic carbon fixation, sulfide oxidation, and ammonia oxidation were also identified and taxonomically affiliated with species of Thiobacillus and Nitrosospira. Furthermore, the abundance of sequences related to Methylobacter¬ combined with the detection of methanogenic taxa provided evidence for methane cycling beneath the AIS. Although organic carbon and nutrients generated in SLW are transported to the WIS-GZ and may help support the diverse community found there, the prevalence of chemolithoautotrophic taxa (e.g., Thioprofundum and Thiohalophilus) suggests primary production coupled to the oxidation of reduced sulfur compounds may also provide a source of new fixed carbon to the system. The WIS-GZ community was distinct from those of SLW and the Ross Ice Shelf edge, signifying that it is structured based on the combined influences of input from the subglacial and marine systems. Collectively, these studies show that ...
format Text
author Achberger, Amanda Marie
author_facet Achberger, Amanda Marie
author_sort Achberger, Amanda Marie
title Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
title_short Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
title_full Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
title_fullStr Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
title_full_unstemmed Structure and Functional Potential of Microbial Communities in Subglacial Lake Whillans and at the Ross Ice Shelf Grounding Zone, West Antarctica
title_sort structure and functional potential of microbial communities in subglacial lake whillans and at the ross ice shelf grounding zone, west antarctica
publisher LSU Digital Commons
publishDate 2016
url https://digitalcommons.lsu.edu/gradschool_dissertations/4453
https://doi.org/10.31390/gradschool_dissertations.4453
https://digitalcommons.lsu.edu/context/gradschool_dissertations/article/5460/viewcontent/Achberger_diss.pdf
long_lat ENVELOPE(-64.250,-64.250,-84.450,-84.450)
ENVELOPE(-145.000,-145.000,-83.667,-83.667)
ENVELOPE(-109.117,-109.117,59.567,59.567)
geographic Antarctic
The Antarctic
West Antarctica
Ross Ice Shelf
Whillans
Whillans Ice Stream
Dark Lake
geographic_facet Antarctic
The Antarctic
West Antarctica
Ross Ice Shelf
Whillans
Whillans Ice Stream
Dark Lake
genre Antarc*
Antarctic
Antarctica
Ice Sheet
Ice Shelf
Ross Ice Shelf
West Antarctica
Whillans Ice Stream
genre_facet Antarc*
Antarctic
Antarctica
Ice Sheet
Ice Shelf
Ross Ice Shelf
West Antarctica
Whillans Ice Stream
op_source LSU Doctoral Dissertations
op_relation https://digitalcommons.lsu.edu/gradschool_dissertations/4453
doi:10.31390/gradschool_dissertations.4453
https://digitalcommons.lsu.edu/context/gradschool_dissertations/article/5460/viewcontent/Achberger_diss.pdf
op_doi https://doi.org/10.31390/gradschool_dissertations.4453
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