Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change
Productivity in the Southern Ocean reflects both the spatial and temporal dynamics of the sea ice ecosystem, as well as the complex cycling of energy through the microbial community. Marine bacteria are thought to be integral to trophodynamics and the functioning of a microbial loop within the ice m...
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2005
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ftvuwellington:oai:researcharchive.vuw.ac.nz:10063/133 2023-08-15T12:38:28+02:00 Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change Martin, Andrew Robert Ryan, Ken 2005 http://researcharchive.vuw.ac.nz/handle/10063/133 en_NZ eng Victoria University of Wellington http://researcharchive.vuw.ac.nz/handle/10063/133 Microbial communities Climate Ecosystem changes Text Master's 2005 ftvuwellington 2023-07-25T17:22:18Z Productivity in the Southern Ocean reflects both the spatial and temporal dynamics of the sea ice ecosystem, as well as the complex cycling of energy through the microbial community. Marine bacteria are thought to be integral to trophodynamics and the functioning of a microbial loop within the ice matrix, but there is no clear understanding of the distribution and diversity of bacteria or the importance of bacterial production. Understanding the bacterial response to environmental change in the sea ice ecosystem may provide an insight into the potential changes to the physical oceanography and ecology of the Southern Ocean. In this study, a multivariate statistical approach was used to compare the distribution and abundance of bacteria occurring in pack ice at the tongue of the Mertz Glacier (George V Coast, Antarctica) with bacteria from fast ice at Cape Hallett (Victoria Land coastline, Antarctica). Estimates of bacterial abundance were derived using both epifluorescence microscopy and flow cytometry and correlated with algal and chlorophyll a data. Significant differences in the vertical distribution of cells within the ice were observed between the Mertz Glacier and Cape Hallett, but no overall difference in cell abundance was found between the two locations with 7.6 ± 1.2 x 109 cells per m2 and 8.7 ± 1.6 x 109 cells per m2 respectively. Bacteria and algae were positively correlated in pack ice of the Mertz Glacier indicating a functional microbial loop, but no discernable relationship was exhibited in multiyear ice at Cape Hallett. These findings support the general consensus that the generation of bacterial biomass from algal-derived dissolved organic matter is highly variable across seasons and habitats. The tetrazolium salt 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) was used to investigate the bacterial response to experimentally induced changes in light and salinity in fast ice at Cape Hallett. Two distinct assemblages were examined; the brine channel assemblage near the surface of the ice and the ... Master Thesis Antarc* Antarctic Antarctica Mertz Glacier Sea ice Southern Ocean Victoria Land Victoria University of Wellington: ResearchArchive Antarctic Cape Hallett ENVELOPE(170.217,170.217,-72.317,-72.317) George V Coast ENVELOPE(147.000,147.000,-69.000,-69.000) Hallett ENVELOPE(170.217,170.217,-72.317,-72.317) Mertz Glacier ENVELOPE(144.500,144.500,-67.667,-67.667) Southern Ocean Victoria Land |
institution |
Open Polar |
collection |
Victoria University of Wellington: ResearchArchive |
op_collection_id |
ftvuwellington |
language |
English |
topic |
Microbial communities Climate Ecosystem changes |
spellingShingle |
Microbial communities Climate Ecosystem changes Martin, Andrew Robert Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
topic_facet |
Microbial communities Climate Ecosystem changes |
description |
Productivity in the Southern Ocean reflects both the spatial and temporal dynamics of the sea ice ecosystem, as well as the complex cycling of energy through the microbial community. Marine bacteria are thought to be integral to trophodynamics and the functioning of a microbial loop within the ice matrix, but there is no clear understanding of the distribution and diversity of bacteria or the importance of bacterial production. Understanding the bacterial response to environmental change in the sea ice ecosystem may provide an insight into the potential changes to the physical oceanography and ecology of the Southern Ocean. In this study, a multivariate statistical approach was used to compare the distribution and abundance of bacteria occurring in pack ice at the tongue of the Mertz Glacier (George V Coast, Antarctica) with bacteria from fast ice at Cape Hallett (Victoria Land coastline, Antarctica). Estimates of bacterial abundance were derived using both epifluorescence microscopy and flow cytometry and correlated with algal and chlorophyll a data. Significant differences in the vertical distribution of cells within the ice were observed between the Mertz Glacier and Cape Hallett, but no overall difference in cell abundance was found between the two locations with 7.6 ± 1.2 x 109 cells per m2 and 8.7 ± 1.6 x 109 cells per m2 respectively. Bacteria and algae were positively correlated in pack ice of the Mertz Glacier indicating a functional microbial loop, but no discernable relationship was exhibited in multiyear ice at Cape Hallett. These findings support the general consensus that the generation of bacterial biomass from algal-derived dissolved organic matter is highly variable across seasons and habitats. The tetrazolium salt 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) was used to investigate the bacterial response to experimentally induced changes in light and salinity in fast ice at Cape Hallett. Two distinct assemblages were examined; the brine channel assemblage near the surface of the ice and the ... |
author2 |
Ryan, Ken |
format |
Master Thesis |
author |
Martin, Andrew Robert |
author_facet |
Martin, Andrew Robert |
author_sort |
Martin, Andrew Robert |
title |
Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
title_short |
Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
title_full |
Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
title_fullStr |
Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
title_full_unstemmed |
Antarctic Bacteria, Sea Ice Ecosystem Dynamics, and Global Climate Change |
title_sort |
antarctic bacteria, sea ice ecosystem dynamics, and global climate change |
publisher |
Victoria University of Wellington |
publishDate |
2005 |
url |
http://researcharchive.vuw.ac.nz/handle/10063/133 |
long_lat |
ENVELOPE(170.217,170.217,-72.317,-72.317) ENVELOPE(147.000,147.000,-69.000,-69.000) ENVELOPE(170.217,170.217,-72.317,-72.317) ENVELOPE(144.500,144.500,-67.667,-67.667) |
geographic |
Antarctic Cape Hallett George V Coast Hallett Mertz Glacier Southern Ocean Victoria Land |
geographic_facet |
Antarctic Cape Hallett George V Coast Hallett Mertz Glacier Southern Ocean Victoria Land |
genre |
Antarc* Antarctic Antarctica Mertz Glacier Sea ice Southern Ocean Victoria Land |
genre_facet |
Antarc* Antarctic Antarctica Mertz Glacier Sea ice Southern Ocean Victoria Land |
op_relation |
http://researcharchive.vuw.ac.nz/handle/10063/133 |
_version_ |
1774299820441206784 |