Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica
During the austral summers of 2004 and 2009, we sampled a supraglacial stream on the Cotton Glacier, Antarctica. The stream dissolved organic matter (DOM) was low (44–48 µ M C) and lacked detectable humic fluorescence signatures. Analysis of the excitation emissions matrices (EEMs) indicated that...
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ftmontanastateu:oai:scholarworks.montana.edu:1/12450 2023-05-15T13:54:59+02:00 Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica Foreman, Christine M. Cory, R. M. Morris, Cindy E. SanClements, M. D. Smith, Heidi J. Lisle, John T. Miller, P. L. Chin, Yu-Ping McKnight, Diane M. 2013-07 application/pdf https://scholarworks.montana.edu/xmlui/handle/1/12450 unknown Foreman CM, Cory RM, Morris CE, SanClements MD, Smith HJ, Lisle JT, Miller PL, Chin Y-P, McKnight DM, "Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica," Environmental Research Letters. July 2013 8(3): 1-11 1748-9326 https://scholarworks.montana.edu/xmlui/handle/1/12450 Article 2013 ftmontanastateu 2022-06-06T07:26:35Z During the austral summers of 2004 and 2009, we sampled a supraglacial stream on the Cotton Glacier, Antarctica. The stream dissolved organic matter (DOM) was low (44–48 µ M C) and lacked detectable humic fluorescence signatures. Analysis of the excitation emissions matrices (EEMs) indicated that amino-acid fluorophores dominated, consistent with DOM of microbial origin, with little humic-like fluorescence. In most aquatic ecosystems, humic DOM attenuates harmful UV radiation and its absence may represent an additional stressor influencing the microbial community. Nonetheless, the stream contained an active microbial assemblage with bacterial cell abundances from 2.94 x 104 to 4.97 x 105 cells ml-1, and bacterial production ranging from 58.8 to 293.2 ng C l-1 d-1. Chlorophyll-a concentrations ranged from 0.3 to 0.53 µ g 1-1 indicating that algal phototrophs were the probable source of the DOM. Microbial isolates produced a rainbow of pigment colors, suggesting adaptation to stress, and were similar to those from other cryogenic systems (Proteobacteria and Bacteroidetes lineages). Supraglacial streams provide an example of contemporary microbial processes on the glacier surface and a natural laboratory for studying microbial adaptation to the absence of humics. Article in Journal/Newspaper Antarc* Antarctica Montana State University (MSU): ScholarWorks Austral Cotton Glacier ENVELOPE(161.667,161.667,-77.117,-77.117) |
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Montana State University (MSU): ScholarWorks |
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ftmontanastateu |
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description |
During the austral summers of 2004 and 2009, we sampled a supraglacial stream on the Cotton Glacier, Antarctica. The stream dissolved organic matter (DOM) was low (44–48 µ M C) and lacked detectable humic fluorescence signatures. Analysis of the excitation emissions matrices (EEMs) indicated that amino-acid fluorophores dominated, consistent with DOM of microbial origin, with little humic-like fluorescence. In most aquatic ecosystems, humic DOM attenuates harmful UV radiation and its absence may represent an additional stressor influencing the microbial community. Nonetheless, the stream contained an active microbial assemblage with bacterial cell abundances from 2.94 x 104 to 4.97 x 105 cells ml-1, and bacterial production ranging from 58.8 to 293.2 ng C l-1 d-1. Chlorophyll-a concentrations ranged from 0.3 to 0.53 µ g 1-1 indicating that algal phototrophs were the probable source of the DOM. Microbial isolates produced a rainbow of pigment colors, suggesting adaptation to stress, and were similar to those from other cryogenic systems (Proteobacteria and Bacteroidetes lineages). Supraglacial streams provide an example of contemporary microbial processes on the glacier surface and a natural laboratory for studying microbial adaptation to the absence of humics. |
format |
Article in Journal/Newspaper |
author |
Foreman, Christine M. Cory, R. M. Morris, Cindy E. SanClements, M. D. Smith, Heidi J. Lisle, John T. Miller, P. L. Chin, Yu-Ping McKnight, Diane M. |
spellingShingle |
Foreman, Christine M. Cory, R. M. Morris, Cindy E. SanClements, M. D. Smith, Heidi J. Lisle, John T. Miller, P. L. Chin, Yu-Ping McKnight, Diane M. Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
author_facet |
Foreman, Christine M. Cory, R. M. Morris, Cindy E. SanClements, M. D. Smith, Heidi J. Lisle, John T. Miller, P. L. Chin, Yu-Ping McKnight, Diane M. |
author_sort |
Foreman, Christine M. |
title |
Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
title_short |
Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
title_full |
Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
title_fullStr |
Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
title_full_unstemmed |
Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica |
title_sort |
microbial growth under humic-free conditions in a supraglacial stream system on the cotton glacier, antarctica |
publishDate |
2013 |
url |
https://scholarworks.montana.edu/xmlui/handle/1/12450 |
long_lat |
ENVELOPE(161.667,161.667,-77.117,-77.117) |
geographic |
Austral Cotton Glacier |
geographic_facet |
Austral Cotton Glacier |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_relation |
Foreman CM, Cory RM, Morris CE, SanClements MD, Smith HJ, Lisle JT, Miller PL, Chin Y-P, McKnight DM, "Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica," Environmental Research Letters. July 2013 8(3): 1-11 1748-9326 https://scholarworks.montana.edu/xmlui/handle/1/12450 |
_version_ |
1766261197337788416 |