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Author Thomas, D.N.; Dieckmann, G.S. (eds) url  isbn
openurl 
  Title Sea ice – an introduction to its physics, chemistry, biology and geology Type Book Whole
  Year 2003 Publication Abbreviated Journal  
  Volume Issue Pages 402 pp  
  Keywords Sea Ice  
  Abstract Sea ice, which covers up to 7% of the planet's surface, is a major component of the world's oceans, partly driving ocean circulation and global climate patterns. It provides a habitat for a rich diversity of marine organisms, and is a valuable source of information in studies of global climate change and the evolution of present day life forms. Increasingly, sea ice is being used as a proxy for extraterrestrial ice covered systems.

Sea Ice provides a comprehensive review of our current available knowledge of polar pack ice, the study of which is severely constrained by the logistic difficulties of working in such harsh and remote regions of the earth. The book's editors, Drs Thomas and Dieckmann have drawn together an impressive group of international contributing authors, providing a well-edited and integrated volume, which will stand for many years as the standard work on the subject. Contents of the book include details of the growth, microstructure and properties of sea ice, large-scale variations in thickness and characteristics, its primary production, micro-and macrobiology, sea ice as a habitat for birds and mammals, sea ice biogeochemistry, particulate flux, and the distribution and significance of palaeo sea ice.
 
  Address Thomas: School of Ocean Sciences, University of Wales, Bangor, UK; Dieckmann: Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany  
  Corporate Author Thesis  
  Publisher Blackwell Science Ltd Place of Publication Oxford Editor Thomas, D.N.; Dieckmann, G.S.  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition (up)  
  ISSN ISBN 0-632-05808-0 Medium  
  Area Expedition Conference  
  Notes 40 Illustrations Approved yes  
  Call Number refbase @ user @ library-34/436/1 Serial 7  
Permanent link to this record
 

 
Author Gomez, I.; Thomas, D.N.; Wiencke, C. openurl 
  Title Longitudinal profiles of growth, photosynthesis and light independent carbon fixation in the Antarctic brown alga Ascoseira mirabilis Type Journal Article
  Year 1995 Publication Botanica Marina Abbreviated Journal Bot Mar  
  Volume 38 Issue Pages 157-164  
  Keywords  
  Abstract Thallus growth, photoynthetic oxygen evolution and rates of carbon fixation were determinedalong the lamina of the endemic Antarctic brown alga Ascoseira mirabilis (Ascoseirales), grown under simulated Antarctic condtions. The meristem is basally located and forms new blade tiddue under spring-conditions. Light saturated net photosynthesis (P,ax), measures as O? production, was higher in ther intermediate region of the plant (9..8 µmol O? g?¹ fw h?¹). In general, photosynthetic parameters such as dark respiration, gross photosynthesis, photosynthetic efficiency (?) and photosynthetic light compensation (Ic) increased significantly towards the distal region. Carbon-fixation in A. mirabilis also showed thllus-dependent variation. Rates of light and light independent (dark) carbon fixation increased towards the distal regions ranging between 7.6-9.5 and 1.2-2.0 µmol C g?¹ fw h?¹ respectively. The percentage of light independent carbon fixation (in relation to light ¹?C-fixation) also increased from the basal to the distal parts reaching 24% in the distal region of the thallus. he contents of Chl a and Chl c, were close to 0.37 and 0.14 mg g?¹ fw respectively and were notably uniform along the lamina. The results indicate that the formation of the blade by a basal meristem and the increase of light carbon fixation rates from base to the distal regions in A. mirabilis are similar compared with certain Laminariales, especially members of the genus Laminaria. However, light independent carbon fixation is highest in the meristem of Laminaria, opposite to the results obtained here for A. mirabilis  
  Address  
  Corporate Author Thesis  
  Publisher de Gruyter Place of Publication Berlin, New York Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition (up)  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Gomez++1995 Serial 736  
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Author Krell, A.; Ummenhofer, C.; Kattner, G.; Naumov, A.; Evans, D.; Dieckmann, G.S.; Thomas, D.N. url  openurl
  Title The biology and chemistry of land fast ice in the White Sea, Russia – A comparison of winter and spring conditions Type Journal Article
  Year 2003 Publication Polar Biology Abbreviated Journal Polar Biol  
  Volume 26 Issue 11 Pages 707-719  
  Keywords  
  Abstract Various abiotic and biotic parameters, including phytoplankton distribution, were studied to investigate seasonal changes within the fast-ice cover in Chupa Inlet, a freshwater-influenced Arctic-like fjord in Kandalaksha Bay (White Sea). Sea ice and under-ice water were collected along transects in the inlet in February and April 2002. Ice-texture analysis, salinity and δ18O values indicated that the complete ice sheet had transformed within 2 months. This resulted from an upward growth of snow ice and subsequent melting at the underside of the ice, which makes a comparison between the two sampling periods difficult in terms of defining temporal developments within the ice. Nutrients, DOC and DON concentrations in the under-ice water were typical for Russian Arctic rivers. Concentrations of nitrate, silicate and DOC in the ice were lower, which is attributed to a loss as the ice forms. The concentrations were also modified by biological activity. In February, there was a strong correspondence between the distribution of biological parameters, including particulate and dissolved organic carbon and nitrogen (POC and PON, DOC and DON) and inorganic nutrients (nitrate, nitrite, phosphate and silicate), which was not the case in April. The correlation between both DOC and DON with ammonium indicates heterotrophic activity within the winter ice collected in February. Sea-ice organisms were distributed throughout the ice, and several assemblages were found in surface layers of the ice. In April, a more typical distribution of biomass in the ice was measured, with low values in the upper part and high algal concentrations in the lower sections of the ice, characteristic of a spring ice-algal bloom. In contrast to the February sampling, there was evidence that the ice-algal assemblage in April was nitrogen-limited, with total inorganic nitrogen concentrations being <1 µ mand a mean inorganic nitrogen to phosphorus ratio of 2.8. The ice assemblages were dominated by diatoms (in particular, Nitzschia spp.). There were temporal shifts in the assemblage composition: in February, diatoms accounted for 40% and in April for >98% of all organisms counted.  
  Address  
  Corporate Author 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 (up)  
  ISSN 0722-4060 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ user @ Krell++2003 Serial 290  
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Author Brierley, A.S.; Thomas, D.N. openurl 
  Title Ecology of southern ocean pack ice Type Journal Article
  Year 2002 Publication Advances in marine biology Abbreviated Journal Adv Mar Biol  
  Volume 43 Issue Pages 171-276  
  Keywords Animals; Antarctic Regions; Birds; Crustacea; Ecology; *Ecosystem; Environment; Fishes; *Ice; *Marine Biology; Oceans and Seas; Phytoplankton; Population Dynamics; Research Support, Non-U.S. Gov't; Seasons; *Seawater; Water Microbiology; Whales  
  Abstract Around Antarctica the annual five-fold growth and decay of sea ice is the most prominent physical process and has a profound impact on marine life there. In winter the pack ice canopy extends to cover almost 20 million square kilometres--some 8% of the southern hemisphere and an area larger than the Antarctic continent itself (13.2 million square kilometres)--and is one of the largest, most dynamic ecosystems on earth. Biological activity is associated with all physical components of the sea-ice system: the sea-ice surface; the internal sea-ice matrix and brine channel system; the underside of sea ice and the waters in the vicinity of sea ice that are modified by the presence of sea ice. Microbial and microalgal communities proliferate on and within sea ice and are grazed by a wide range of proto- and macrozooplankton that inhabit the sea ice in large concentrations. Grazing organisms also exploit biogenic material released from the sea ice at ice break-up or melt. Although rates of primary production in the underlying water column are often low because of shading by sea-ice cover, sea ice itself forms a substratum that provides standing stocks of bacteria, algae and grazers significantly higher than those in ice-free areas. Decay of sea ice in summer releases particulate and dissolved organic matter to the water column, playing a major role in biogeochemical cycling as well as seeding water column phytoplankton blooms. Numerous zooplankton species graze sea-ice algae, benefiting additionally because the overlying sea-ice ceiling provides a refuge from surface predators. Sea ice is an important nursery habitat for Antarctic krill, the pivotal species in the Southern Ocean marine ecosystem. Some deep-water fish migrate to shallow depths beneath sea ice to exploit the elevated concentrations of some zooplankton there. The increased secondary production associated with pack ice and the sea-ice edge is exploited by many higher predators, with seals, seabirds and whales aggregating there. As a result, much of the Southern Ocean pelagic whaling was concentrated at the edge of the marginal ice zone. The extent and duration of sea ice fluctuate periodically under the influence of global climatic phenomena including the El Nino Southern Oscillation. Life cycles of some associated species may reflect this periodicity. With evidence for climatic warming in some regions of Antarctica, there is concern that ecosystem change may be induced by changes in sea-ice extent. The relative abundance of krill and salps appears to change interannually with sea-ice extent, and in warm years, when salps proliferate, krill are scarce and dependent predators suffer severely. Further research on the Southern Ocean sea-ice system is required, not only to further our basic understanding of the ecology, but also to provide ecosystem managers with the information necessary for the development of strategies in response to short- and medium-term environmental changes in Antarctica. Technological advances are delivering new sampling platforms such as autonomous underwater vehicles that are improving vastly our ability to sample the Antarctic under sea-ice environment. Data from such platforms will enhance greatly our understanding of the globally important Southern Ocean sea-ice ecosystem.  
  Address Gatty Marine Laboratory, School of Biology, University of St Andrews, Fife, KY16 8LB, UK. andrew.brierley@st-andrews.ac.uk  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition (up)  
  ISSN 0065-2881 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12154613 Approved no  
  Call Number refbase @ user @ Serial 317  
Permanent link to this record
 

 
Author Gleitz, M.; Rutgers v d Loeff, M.; Thomas, D.N.; Dieckmann, G.S.; Millero, F.J. url  openurl
  Title Comparison of summer and winter inorganic carbon, oxygen and nutrient concentrations in Antarctic sea ice brine Type Journal Article
  Year 1995 Publication Marine Chemistry Abbreviated Journal Mar Chem  
  Volume 51 Issue 2 Pages 81-91  
  Keywords dissolved oxygen; inorganic compounds; summer; winter; nutrients (mineral); Antarctic zone; sea ice; brines; carbon; chemical composition; Psw; Weddell Sea; polar zones; polar regions; nutrients  
  Abstract During summer (January 1991) and winter (April 1992) cruises to the southern Weddell Sea (Antarctica), brine samples were collected from first year sea ice and analysed for salinity, temperature, dissolved oxygen and major nutrient concentrations. Additionally, the carbonate system was determined from measurements of pH and total alkalinity. During winter, brine chemical composition was largely determined by seawater concentration in the course of freezing. Brine temperatures ranged from -1.9 to -6.7 °C. Precipitation of calcium carbonate was not observed at the corresponding salinity range of 34 to 108. Removal of carbon from the total inorganic carbon pool (up to 500 µmol Ct kg?¹) was related to reduced nutrient concentrations, indicating the presence of photosynthetically active ice algal assemblages in the winter sea ice. However, nutrient and inorganic carbon concentrations did generally not reach growth limiting levels for phytoplankton. The combined effect of photosynthesis and physical concentration resulted in O? concentrations of up to 650 µmol kg?¹. During summer, brine salinities ranged from 21 to 41 with most values >28, showing that the net effect of freezing and melting on brine chemical composition was generally slight. Opposite to the winter situation, brine chemical composition was strongly influenced by biological activity. Photosynthetic carbon assimilation resulted in a Ct depletion of up to 1200 µmol kg?¹, which was associated with CO? (aq) exhaustion and O? concentrations as high as 933 µmol kg?¹. The concurrent depletion of major nutrients generally corresponded to uptake ratios predicted from phytoplankton biochemical composition. Primary productivity in summer sea ice is apparently sustained until inorganic resources are fully exhausted, resulting in brine chemical compositions that differ profoundly from those of surface waters. This may have important implications for pathways of ice algal carbon acquisition, carbon isotope fractionation as well as for species distribution in the open water phytoplankton.  
  Address  
  Corporate Author 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 (up)  
  ISSN 0304-4203 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Gleitz++1995 Serial 733  
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