RRNA and rDNA based assessment of sea ice protist biodiversity from the central Arctic Ocean. Issue 1 (2nd January 2016)

• Record Type: Journal Article
• Authors: Stecher, Anique; Neuhaus, Stefan; Lange, Benjamin; Frickenhaus, Stephan; Beszteri, Bánk; Kroth, Peter G.; Valentin, Klaus
• Is Part Of: European journal of phycology. Volume 51:Issue 1(2016)
• Page Start: 31
• Page End: 46
• Publication Date: 2016-01-02
• Subjects: 18S rDNA -- 18S rRNA -- 454 sequencing -- alveolates -- Arctic Ocean -- diatoms -- sea ice; Algology -- Periodicals; Algae -- Periodicals; 579.8
• DOI: 10.1080/09670262.2015.1077395
• Languages: English
• ISSNs: 0967-0262

Abstract

Abstract: Sea ice is a large and diverse ecosystem contributing significantly to primary production in ice-covered regions. In the Arctic Ocean, sea ice consists of mixed multi-year ice (MYI), often several metres thick, and thinner first-year ice (FYI). Current global warming is most severe in Arctic regions; as a consequence, summer sea ice cover is decreasing and MYI is disappearing at an alarming rate. Despite its apparent hostility, sea ice is inhabited by a diverse microbial community of bacteria and protists, many of which are photosynthetic. Here we present an assessment of eukaryotic biodiversity in MYI and FYI from the central Arctic Ocean using high-throughput 454 sequencing of 18S rRNA and rDNA amplicons. We compared the rDNA-based 'total' biodiversity with the 'active' biodiversity from rRNA amplicons and found differences between them including an over-representation of Ciliophora, Bicosoecida and Bacillariophyceae operational taxonomic units (OTUs) in the active part of the community. Differences between the two libraries are more pronounced at the lower taxonomic level: certain genera, such as Melosira, are more abundant in the rRNA library, indicating activity of these genera. Furthermore, we found that one FYI station showed a higher activity of potential grazers which was probably due to the advanced stage of melt evident by higher ice temperatures and highly porous ice compared with the other stations.