An active bacterial community linked to high chl-a concentrations in Antarctic winter-pack ice and evidence for the development of an anaerobic sea-ice bacterial community

Abstract Antarctic sea-ice bacterial community composition and dynamics in various developmental stages were investigated during the austral winter in 2013. Thick snow cover likely insulated the ice, leading to high (<4 μg l−1) chlorophyll-a (chl-a) concentrations and consequent bacterial pro...

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Bibliographic Details
Published in:The ISME Journal
Main Authors: Eronen-Rasimus, Eeva, Luhtanen, Anne-Mari, Rintala, Janne-Markus, Delille, Bruno, Dieckmann, Gerhard, Karkman, Antti, Tison, Jean-Louis
Format: Article in Journal/Newspaper
Language:English
Published: Oxford University Press (OUP) 2017
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Online Access:http://dx.doi.org/10.1038/ismej.2017.96
http://www.nature.com/articles/ismej201796.pdf
http://www.nature.com/articles/ismej201796
https://academic.oup.com/ismej/article-pdf/11/10/2345/56140753/41396_2017_article_bfismej201796.pdf
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Summary:Abstract Antarctic sea-ice bacterial community composition and dynamics in various developmental stages were investigated during the austral winter in 2013. Thick snow cover likely insulated the ice, leading to high (<4 μg l−1) chlorophyll-a (chl-a) concentrations and consequent bacterial production. Typical sea-ice bacterial genera, for example, Octadecabacter, Polaribacter and Glaciecola, often abundant in spring and summer during the sea-ice algal bloom, predominated in the communities. The variability in bacterial community composition in the different ice types was mainly explained by the chl-a concentrations, suggesting that as in spring and summer sea ice, the sea-ice bacteria and algae may also be coupled during the Antarctic winter. Coupling between the bacterial community and sea-ice algae was further supported by significant correlations between bacterial abundance and production with chl-a. In addition, sulphate-reducing bacteria (for example, Desulforhopalus) together with odour of H2S were observed in thick, apparently anoxic ice, suggesting that the development of the anaerobic bacterial community may occur in sea ice under suitable conditions. In all, the results show that bacterial community in Antarctic sea ice can stay active throughout the winter period and thus possible future warming of sea ice and consequent increase in bacterial production may lead to changes in bacteria-mediated processes in the Antarctic sea-ice zone.