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Author Arrigo, K.R.; Thomas, D.N. url  openurl
  Title Large scale importance of sea ice biology in the Southern Ocean Type Journal Article
  Year 2004 Publication (up) Antarctic Science Abbreviated Journal Antarct Sci  
  Volume 16 Issue 4 Pages 471-486  
  Keywords algae; Antarctic; biogeochemistry; carbon cycle; primary production; Full Data Records  
  Abstract Despite being one of the largest biomes on earth, sea ice ecosystems have only received intensive study over the past 30 years. Sea ice is a unique habitat for assemblages of bacteria, algae, protists, and invertebrates that grow within a matrix dominated by strong gradients in temperature, salinity, nutrients, and UV and visible radiation. A suite of physiological adaptations allow these organisms to thrive in ice, where their enormous biomass makes them a fundamental component of polar ecosystems. Sea ice algae are an important energy and nutritional source for invertebrates such as juvenile krill, accounting for up to 25% of total annual primary production in ice-covered waters. The ability of ice algae to produce large amounts of UV absorbing compounds such as mycosporine-like amino acids makes them even more important to organisms like krill that can incorporate these sunscreens into their own tissues. Furthermore, the nutrient and light conditions in which sea ice algae thrive induce them to synthesize enhanced concentrations of polyunsaturated fatty acids, a vital constituent of the diet of grazing organisms, especially during winter. Finally, sea ice bacteria and algae have become the focus of biotechnology, and are being considered as proxies of possible life forms on ice-covered extraterrestrial systems. An analysis of how the balance between sea ice and pelagic production might change under a warming scenario indicates that when current levels of primary production and changes in the areas of sea ice habitats are taken into account, the expected 25% loss of sea ice over the next century would increase primary production in the Southern Ocean by approximately 10%, resulting in a slight negative feedback on climate warming.  
  Address  
  Corporate Author Thesis  
  Publisher Cambridge University Press Place of Publication Cambridge 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 Review Approved no  
  Call Number refbase @ admin @ Arrigo+Thomas2004 Serial 729  
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Author Herborg, L.-M.; Thomas, D.N.; Kennedy, H.; Haas, C.; Dieckmann, G.S. url  openurl
  Title Dissolved carbohydrates in Antarctic sea ice Type Journal Article
  Year 2001 Publication (up) Antarctic Science Abbreviated Journal Antarct Sci  
  Volume 13 Issue 2 Pages 119-125  
  Keywords Doc; Mcho; Pcho; sea ice; bacteria; carbon cycling; diatoms; dissolved organic carbon; monocarbohydrates; polycarbohydrates  
  Abstract Concentrations of dissolved monocarbohydrates (MCHO) and polycarbohydrates (PCHO) were analysed in a variety of ice habitats from summer Weddell Sea sea ice (surface ponds, ice cores, gap layers and platelet ice). The dissolved organic carbon (DOC) pool in these habitats was also measured and the contribution of carbohydrate to this pool was assessed. The DOC concentrations within all sea ice habitats were high compared to surface seawater concentrations with values up to 958µMC being measured. Total carbohydrates (TCHO) were highest in the ice cores and platelet ice samples, up to 3 1% of the DOC pool, a reflection of the high algal biomass in these two habitat classes. TCHO in the other habitats ranged between 10% and 29% of DOC. The ratios of MCHO to PCHO varied considerably between the ice habitats: in surface ponds and ice cores MCHO was 70% of the TCHO pool, whereas in gap layers and platelet ice there were lower PCHO concentrations resulting in MCHO being 88% of TCHO.  
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  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Herborg++2001 Serial 743  
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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 (up) 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.  
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  Corporate Author 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 Dieckmann, G.S.; Eicken, H.; Haas, C.; Garrison, D.L.; Gleitz, M.; Lange, M.; Nöthig, E.-M.; Spindler, M.; Sullivan, C.W.; Thomas, D.N.; Weissenberger, J. isbn  openurl
  Title A compilation of data on sea ice algal standing crop from the Bellingshausen, Amundsen and Weddell Seas from 1983 to 1994 Type Book Chapter
  Year 1998 Publication (up) Antarctic sea ice: Biological processes, interactions and variability Abbreviated Journal  
  Volume Issue Pages 85-92  
  Keywords Algae; Biomass; Ecology; Ice composition; Antarctica; Bellingshausen Sea; Amundsen Sea; Weddell Sea  
  Abstract Algal standing stock as chlorophyll a in sea ice was compiled from 448 cores collected during 13 U.S. and German research cruises to Antarctica between 1983 and 1994. The data have a high variability and show no clear relationships with other parameters such as core length. However, seasonal variations in standing stock are discernable. The authors recommend that due to the high variability in the data and inconsistency of sampling methods, the data be used with caution, since they do not represent all sea ice habitats. We provide the data due to the current need for such information for the parameterization of models.  
  Address  
  Corporate Author Thesis  
  Publisher American Geophysical Union Place of Publication Washington, DC Editor Lizotte, M.P.; Arrigo, K.R.  
  Language Summary Language Original Title  
  Series Editor Series Title Antarctic Research Series Abbreviated Series Title  
  Series Volume 73 Series Issue Edition  
  ISSN ISBN 0-87590-901-9 Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Dieckmann++1998 Serial 731  
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Author Thomas, D.N.; Lara, R.J.; Haas, C.; Schnack-Schiel, S.B.; Dieckmann, G.S.; Kattner, G.; Nöthig, E.-M.; Mizdalski, E. url  isbn
openurl 
  Title Biological soup within decaying summer sea ice in the Amundsen Sea, Antarctica Type Book Chapter
  Year 1998 Publication (up) Antarctic sea ice: Biological processes, interactions and variability Abbreviated Journal  
  Volume Issue Pages 161-171  
  Keywords Marine biology; Algae; Ice composition; Pack ice; Decomposition; Ecology; Nutrient cycle; Antarctica; Amundsen Sea  
  Abstract In late February 1994, during the ANT XI/3 expedition of R/V Polarstern, ice cores from perennial sea ice were sampled in the Amundsen Sea in areas of dense pack ice. The ice was largely rotten, and a conspicuous feature was the occurrence of thick gaps and voids, often filled with a dark brown slush comprised of loose ice chunks and crystals. These interior ice assemblages were at depths between 1.0 and 1.5 m in 3 to 4 m thick ice floes, and had remarkably rich interior ice algal assemblages (<= 377 µg Chl a L?¹) which were in turn a food source for unusually large numbers of foraminifers (<= 1262 individuals L?¹), the calanoid copepod Stephos longipes (<= 163 individuals L?¹) and harpacticoid copepods (<= 168 individuals L?¹). Analysis of inorganic nutrients (nitrate, phosphate, ammonium, nitrite, and silicate) and dissolved organic carbon (DOC) showed that these were sites of high nutrient supply coupled with high rates of nutrient regeneration.  
  Address  
  Corporate Author Thesis  
  Publisher American Geophysical Union Place of Publication Washington, DC Editor Lizotte, M.P.; Arrigo, K.R.  
  Language Summary Language Original Title  
  Series Editor Series Title Antarctic Research Series Abbreviated Series Title  
  Series Volume 73 Series Issue Edition  
  ISSN ISBN 0-87590-901-9 Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Thomas++1998 Serial 764  
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