Ciliate biodiversity in Antarctic and Arctic freshwater habitats – a bipolar comparison
Abstract:Ciliate biodiversity and community composition was investigated in vivo and after silver impregnations in polar freshwater ecosystems in summer. In total, 334 species from at least 117 genera were found. 210 species (98 genera) occurred in the Arctic (Svalbard, 79°N), 120 spp. (73 genera) in the maritime Antarctic (Livingston Island, 63°S) and 59 spp. (41 genera) in the continental Antarctic (Victoria Land, 75°S). In Antarctica, however, freshwater ciliate communities are distinctly depauperized compared to those in the Arctic and species diversity decreases by about 5 spp./° latitude southwards, i.e. environmental conditions become more severe. While Litostomatea and Stichotrichia together comprised more than 40% of the species in all regions, a higher proportion of nassophorean (14%) and scuticociliate species (12%) occurred in the climatically more extreme Victoria Land than in the other locations. No colpodids were found in Victoria Land samples, while 9–12 species were found in Arctic and maritime Antarctic inland waters. Some genera, e.g. Stentor, Trithigmostoma, as well as mixotrophic species were widespread in the Arctic but not found in the maritime or continental Antarctic, but cyanobacterivores reached their highest proportion (13%) furthest south. Comparisons with the ciliate faunas of terrestrial and marine biotopes showed that a separate limnetic coenosis exists in both polar regions.
Document Type: Research Article
Affiliations: Institute of Zoology, University of Salzburg, Hellbrunnerstr. 34, A-5020 Salzburg, Austria;, Email: email@example.com
Publication date: December 1, 2003