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  • From the abstract of the referenced paper: Spring phytoplankton communities in the water column of Ellis Fjord are characterised by diatoms originating from the bottom sea-ice strand community. Upon ice break-out in early summer, these are replaced by blooms of the phytoflagellates, Phaeocystis puchetii, Cryptomonas cryophila, Pyramimonas gelidicola, silicoflagellates and dinoflagellates. The narrow entrance of the fjord and the development of summer stratification is probably limiting the availability of nutrients and containing the magnitude of the small bloom (maximum 2.8 million cells per litre).

  • Metadata record for data from ASAC Project 2146 See the link below for public details on this project. From the abstracts of the referenced papers: Early season phytoplankton communities in both Omega and Taynaya Bays are characterised by diatoms sedimenting out of the overlying sea ice. Initial nitrate, phosphate and silicate levels are high and the bay waters are covered with ice and well mixed. In Taynaya Bay the ice cover is retained throughout the season while Omega Bay is free for 6-8 weeks. After ice break out in Omega Bay, the phytoplankton community changes from one dominated by diatoms to one dominated by the phtyoflagellates, Pyramimonas spp., Cryptomonas sp. and Gymnodinium sp. In Taynaya Bay the ice remained and even though phtyoflagellates became more common, diatoms still dominated. These differences in community composition result from differences in light climate, extent of stratification and nutrient levels. Sediment cores from Abel and Platcha Bays, in the Vestfold Hills, east Antarctica, contain evidence for a local late Holocene increase in fast ice extent and a possible ice cap retreat at approximately 1750 yr BP, a similar time to the Chelnock Glaciation. Prior to this time both bays experienced periods of isolation that lead to changes in their diatom flora, C:N ratio, percentage of biogenic silica and total organic carbon. Three new diatom indices are proposed; the fast ice index, based on the proportion of benthic taxa and the snow index, based on the proportion of Berkelaya adeliense and Thalassiosira australis. These indices show strong relationships with the percentage of biogenic silica, total organic carbon and percentage sand. A weak relationship exists between the fast ice index and delta 13 C and no relationship with the C:N ratio. The fields in these datasets are: Date Julian Day Sample Volume filtered (L) Acetone Volume (ml) Abs Chlorophyll Phytoplankton