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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.  
  Address  
  Corporate Author Thesis  
  Publisher Natural History Museum Place of Publication London Editor Coyne, C.  
  Language Summary Language Original Title (up)  
  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 Thesis  
  Publisher Elsevier Science B.V. Place of Publication Amsterdam Editor  
  Language Summary Language Original Title (up)  
  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 Thesis  
  Publisher Taylor & Francis Place of Publication London Editor Gibson, R.N.; Barnes, M.; Atkinson, R.J.A.  
  Language Summary Language Original Title (up)  
  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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Author Thomas, D.N.; Dieckmann, G.S. url  openurl
  Title Antarctic sea ice – a habitat for extremophiles Type Journal Article
  Year 2002 Publication Science Abbreviated Journal Science  
  Volume 295 Issue 5555 Pages 641-644  
  Keywords Microorganisms; Sea ice; Ecosystems; Polar zones; Antarctic zone; Epontic organisms; Sea ice ecology; Antarctic sea ice; Marine microorganisms; Marine ecosystems; Bacteria; Algae; Psychrophilic bacteria; extremophiles; Ps; Antarctica  
  Abstract The pack ice of Earth's polar oceans appears to be frozen white desert, devoid of life. However, beneath the snow lies a unique habitat for a group of bacteria and microscopic plants and animals that are encased in an ice matrix at low temperatures and light levels, with the only liquid being pockets of concentrated brines. Survival in these conditions requires a complex suite of physiological and metabolic adaptations, but sea-ice organisms thrive in the ice, and their prolific growth ensures they play a fundamental role in polar ecosystems. Apart from their ecological importance, the bacterial and algae species found in sea ice have become the focus for novel biotechnology, as well as being considered proxies for possible life forms on ice- covered extraterrestrial bodies.  
  Address  
  Corporate Author Thesis  
  Publisher American Association for the Advancement of Science Place of Publication Washington, DC Editor  
  Language Summary Language Original Title (up)  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-8075 ISBN Medium  
  Area Expedition Conference  
  Notes Review Approved no  
  Call Number refbase @ admin @ Thomas+Dieckmann2002_2 Serial 759  
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Author Thomas, D.N.; Gleitz, M. url  openurl
  Title Allocation of photoassimilated carbon into major algal metabolite fractions: Variation between two diatom species isolated from the Weddell Sea (Antarctica) Type Journal Article
  Year 1993 Publication Polar Biology Abbreviated Journal Polar Biol  
  Volume 13 Issue 4 Pages 281-286  
  Keywords carbon fixation; metabolites; biomass; Nitzschia curta; Chaetoceros; Psw; Weddell Sea  
  Abstract Distribution of photoassimilated carbon into major metabolite classes differed between two Antarctic diatom species, Nitzschia curta and a small unicellular Chaetoceros sp.. Time course uptake studies (over 54 h) revealed that¹?C allocation appeared to be equilibrated after approximately 8 h at light saturated photosynthesis. During short term dark periods (6 h), polysaccharides as well as low-molecular-weight compounds were catabolised to sustain protein synthesis in the dark, whilst lipid reserves were not mobilised for this process. Experiments with these two species were conducted at 0 and -1.5 degree C, although no difference in the distribution of radiolabel was measured between the two temperatures. It is hypothesised that under near-optimal conditions fast growing species are characterised by a high carbon turnover associated with a rapid flow of newly assimilated carbon into polymeric compound classes. On the other hand, slower growing species (such as N. curta) may store a significant amount of surplus carbon in the low-molecular-weight metabolite fraction. Species specific preferences were observed when comparing the accumulation of radiolabel into the lipid pools.  
  Address  
  Corporate Author Thesis  
  Publisher Springer-Verlag Place of Publication Heidelberg Editor  
  Language Summary Language Original Title (up)  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0722-4060 ISBN Medium  
  Area Expedition Conference  
  Notes Bibliogr.: 48 ref.; Marine Approved no  
  Call Number refbase @ admin @ Thomas+Gleitz1993 Serial 760  
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