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Author Schnack-Schiel, S.B.; Dieckmann, G.S.; Kattner, G.; Thomas, D.N. url  openurl
  Title Copepods in summer platelet ice in the eastern Weddell Sea, Antarctica Type Journal Article
  Year 2004 Publication Polar Biology Abbreviated Journal Polar Biol  
  Volume 27 Issue 8 Pages 502-506  
  Keywords  
  Abstract Copepods in platelet-ice layers underlying fast ice and in the water column below were studied at Drescher Inlet, eastern Weddell Sea in February 1998. Three copepod species were found: Drescheriella glacialis and Paralabidocera antarctica occurred in platelet-ice layers, while Stephos longipes was only present in the water column. The distribution of all species varied considerably between station and depth. D. glacialis dominated the platelet-ice community and occurred at all five platelet-ice sampling sites, except one, with numbers of up to 26 ind. l?¹. In contrast, P. antarctica was only found in low numbers (up to 2 ind. l?¹) at one site. The total copepod abundance in the platelet ice was not associated with algal biomass, although it was strongly correlated with high ammonium concentrations (up to 9 µM) in the interstitial water between the platelets. This is the first indirect evidence to support the hypothesis that zooplankton excretion can partly account for the high ammonium values often found in platelet-ice layers.  
  Address  
  Corporate Author (down) Thesis  
  Publisher Springer-Verlag Place of Publication Heidelberg Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0722-4060 ISBN Medium  
  Area Expedition Conference  
  Notes Short note Approved no  
  Call Number refbase @ admin @ Schnack-Schiel++2004 Serial 752  
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Author Schnack-Schiel, S.B.; Thomas, D.N.; Haas, C.; Dieckmann, G.S.; Alheit, R. url  openurl
  Title The occurrence of the copepods Stephos longipes (Calanoida) and Drescheriella glacialis (Harpacticoida) in summer sea ice in the Weddell Sea, Antarctica Type Journal Article
  Year 2001 Publication Antarctic Science Abbreviated Journal Antarctic Sci  
  Volume 13 Issue 2 Pages 150-157  
  Keywords copepods; Drescheriella glacialis; sea ice; seasonality; Stephos longipes  
  Abstract In January to March 1997, a RV Polarstern cruise that transected the Weddell Sea resulted in samples being taken in thick pack ice in the south-eastern Weddell Sea and then along the marginal ice edge towards the Antarctic Peninsula. Several ice types were thus sampled over a wide geographic area during late summer/early autumn. Common features of the first warm period was the occurrence of surface ponds, and that many floes had quasi-continuous horizontal gaps, underlying a layer of ice and metamorphic snow. With the onset of cold air temperatures in late February the gaps rapidly refroze. The calanoid copepod Stephos longipes occurred in all habitats encountered and showed highest numbers in the surface ice in summer, in the gap water during both seasons and in the refrozen gap water in autumn. Nauplii outnumbered copepodids in the surface ice and refrozen gap water, while in the gap water copepodids, mainly stages CI-CIII in summer and CII-CIV in autumn, comprised about 70% of the total population. The harpacticoid species Drescheriella glacialis did not occur in all habitats and was missing in surface ponds and new ice. Nauplii of D. glacialis were rarely found in gapwater, but predominated in the refrozen gaps.  
  Address  
  Corporate Author (down) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0954-1020 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Schnack-Schiel++2001_2 Serial 753  
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Author Thomas, D.N. url  isbn
openurl 
  Title Frozen Oceans – The floating world of pack ice Type Book Whole
  Year 2004 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract Pack ice is a layer of frozen seawater on the top of the polar oceans, varying in thickness from a few centimetres to tens of metres. It is an ephemeral feature, not just of polar regions but also of seas such as the Baltic, Caspian and Sea of Okhotsk. At its maximum extent it covers 13% of the Earth's surface area, making it one of the major biomes on the planet.For many years seen as an obstacle to trade and a threat to human life, the ice itself is now perceived to be vulnerable as we come to realize the dangers posed by global warming. Sea ice not only dominates polar regions but is also central to global ocean circulation as well as global climate patterns. Every year the formation, consolidation and subsequent melt of millions of square kilometres of ice influence the whole of the ocean's ecosystems.This is the first book to offer the general reader access to a remote frozen habitat which has for so long fascinated explorers, writers and scientists. During the harsh polar winter the surface of the ocean freezes up, forming a temporary ice layer called pack ice, or sea ice. This gives rise to a spectacular floating world which for a number of months each year becomes home to a wealth of plant and animal life. The wonderful colour photographs of life on, in and under the ice help draw the reader into this superb account of an extreme environment. Guaranteed to capture the imagination.The author is a veteran of six expeditions to the Arctic and Antarctic, and this book is packed with photographs taken in the course of his journeys. His lively and readable text conveys his excitement at the dangers and possibilities of life on the ice. He provides an in-depth background to the whole ecosystem of sea ice, its living communities and the structure of the ice itself. The level of accurate scientific detail will satisfy anyone looking for a reliable, up-to-date overview of this topic.  
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  Publisher Natural History Museum Place of Publication London Editor Coyne, C.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 0-565-09188-3 Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Thomas2004 Serial 756  
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Author Thomas, D.N.; Baumann, M.E.M.; Gleitz, M. url  openurl
  Title Efficiency of carbon assimilation and photoacclimation in a small unicellular Chaetoceros species from the Weddell Sea (Antarctica): Influence of temperature and irradiance Type Journal Article
  Year 1992 Publication Journal of Experimental Marine Biology and Ecology Abbreviated Journal J Exp Mar Biol Ecol  
  Volume 157 Issue 2 Pages 195-209  
  Keywords photosynthesis; Psw; Weddell Sea; Chaetoceros; temperature effects; irradiance; light effects; acclimation; respiration; carbon fixation; low temperature; polar waters; Antarctica; water temperature  
  Abstract It is well established that Antarctic phytoplankton and sea-ice algae are able to thrive at low temperatures and it has been proposed that a reduction in respiration may be important in enabling them to do this. This possibility was studied in an Antarctic clone of a small unicellular Chaetoceros species isolated from the Weddell Sea (Antarctica), using comparative measurements of C assimilation during long- and short-term incubation series over a range of temperatures (-1.5 to 4 °C) at two irradiances (5 and 55 µmol m?²/s). Even though doubling times varied considerably, the total amount of C assimilated per cell per generation time was similar at each of the temperature and light conditions. However, over one cell cycle, significant respiratory C losses were determined by divergences in C assimilation patterns between cumulative and long-term incubations at both light intensities at 0 and 4 °C. At -1.5 °C, insignificant C losses were recorded. No significant extracellular release of dissolved organic material (DOC) was observed.  
  Address  
  Corporate Author (down) Thesis  
  Publisher Elsevier Science B.V. Place of Publication Amsterdam Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0981 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Thomas++1992 Serial 757  
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Author Thomas, D.N.; Dieckmann, G.S. openurl 
  Title Biogeochemistry of Antarctic sea ice Type Journal Article
  Year 2002 Publication Oceanography and Marine Biology: An Annual Review Abbreviated Journal Oceanogr Mar Biol Annu Rev  
  Volume 40 Issue Pages 143-169  
  Keywords Sea ice; Biogeochemistry; Nutrients (mineral); Dissolved gases; Dissolved organic matter; Ps; Antarctic Ocean  
  Abstract Antarctic sea ice at its maximum extent in winter covers 40% of the Southern Ocean in a frozen layer, on average, 1 m thick. Sea ice is not solid, rather it is an ice crystal matrix permeated by a labyrinth of brine filled channels and pores in which life thrives. Organisms are constrained by a set of physicochemical factors quite unlike anything they encounter in the plankton from where they are recruited. Because sea ice is increasingly viewed as a suitable proxy for life in previous periods of the Earth's history, and even for astrobiology, it is pertinent that the physicochemical constraints acting upon sea-ice biology are better understood. The, largely microbial, network that develops in the ice itself imparts a unique chemistry that influences the nature and chemical composition of biogenic material released from the ice. This chemistry can result in the export of material to the sediments with distinctive chemical signatures that are useful tools for reconstructing past sea-ice cover of the oceans. This review synthesises information on inorganic nutrient, dissolved organic matter and dissolved gases from a variety of Antarctic ice habitats.  
  Address  
  Corporate Author (down) Thesis  
  Publisher Taylor & Francis Place of Publication London Editor Gibson, R.N.; Barnes, M.; Atkinson, R.J.A.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0415254620 ISBN Medium  
  Area Expedition Conference  
  Notes Review; Marine Approved no  
  Call Number refbase @ admin @ Thomas+Dieckmann2002 Serial 758  
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