(Table 1) Abundance of unicellular eukaryotes in ice cores collected during the July 2008 CCGS Amundsen cruise in Darnley Bay

• Main Author: Mundy, Christopher John
• Format: Dataset
• Language: English
• Published: PANGAEA 2011
• Subjects: Amphidinium spp.; Amundsen_Gulf08; Amundsen Gulf; Canada; Arcocellulus cornucervis; Attheya cf. septentrionalis; Attheya septentrionalis; Bicosta spp.; Bodo cf. curvifilus; Bodo spp.; Calliacantha longicaudata; Calliacantha natans; Chaetoceros cf. convolutus; Chaetoceros cf. minimus; Chaetoceros neogracile; Chaetoceros similis; Chaetoceros simplex; Chaetoceros socialis; Chaetoceros sp.; Chaetoceros spp.; Chaetoceros tenuissimus; Chaetoceros vistulae; Chaetoceros wighamii; Chattonella spp.; Chlorophyceae; Chlorophyceae indeterminata; Choanoflagellatea indeterminata; Choanoflagellida; Chrysochromulina spp.; Chrysophyceae; Chrysophyceae cysts; Chrysophyceae indeterminata; Ciliates; Ciliates indeterminata; Cryptophyceae; Cryptophyceae indeterminata; Cylindrotheca closterium; DATE/TIME; Diatoms; pennales indeterminata; Dicrateria spp.; Dictyochophyceae; Dinobryon balticum; Dinobryon faculiferum; Dinobryon spp.; Dinoflagellate indeterminata; Dinoflagellates; Dolichomastix nummulifera; Ephemera planamembranacea; Darnley Bay; Polar Biology
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.817323; https://doi.org/10.1594/PANGAEA.817323

Influence of methanogenic populations in Holocene lacustrine sediments revealed by clone libraries and fatty acid biogeochemistry.Biological characteristics of ice-associated algal communities were studied in Darnley Bay (western Canadian Arctic) during a 2-week period in July 2008 when the landfast ice cover had reached an advanced stage of melt. We found two distinct and separate algal communities: (1) an interior ice community confined to brine channel networks beneath white ice covers; and (2) an ice melt water community in the brackish waters of both surface melt ponds and the layer immediately below the ice cover. Both communities reached maximum chlorophyll a concentrations of about 2.5 mg/m**3, but with diatoms dominating the interior ice while flagellates dominated the melt water community. The microflora of each community was diverse, containing both unique and shared algal species, the latter suggesting an initial seeding of the ice melt water by the bottom ice community. Absorption characteristics of the algae indicated the presence of mycosporine-like amino acids (MAAs) and carotenoid pigments as a photoprotective strategy against being confined to high-light near-surface layers. Although likely not contributing substantially to total annual primary production, these ice-associated communities may play an important ecological role in the Arctic marine ecosystem, supplying an accessible and stable food source to higher trophic levels during the period of ice melt.