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Author Granskog, M.A.; Kaartokallio, H.; Kuosa, H.; Thomas, D.N.; Ehn, J.; Sonninen, E. url  doi
openurl 
  Title Scales of horizontal patchiness in chlorophyll a, chemical and physical properties of landfast sea ice in the Gulf of Finland (Baltic Sea) Type Journal Article
  Year 2005 Publication Polar Biology Abbreviated Journal Polar Biol  
  Volume 28 Issue 4 Pages 276-283  
  Keywords  
  Abstract Horizontal variation of first-year landfast sea ice properties was studied in the Gulf of Finland, the Baltic Sea. Several scales of variation were considered; a number of arrays with core spacings of 0.2, 2 and 20 m were sampled at different stages of the ice season for small-scale patchiness. Spacing between these arrays was from hundreds of meters to kilometers to study mesoscale variability, and once an onshore–offshore 40-km transect was sampled to study regional scale variability. Measured variables included salinity, stable oxygen isotopes (δ18O), chlorophyll a (chl-a), nutrients and dissolved organic carbon. On a large scale, a combination of variations in the under-ice water salinity (ice porosity), nutrient supply and the stage of ice development control the build-up of ice algal biomass. At scales of hundreds of meters to kilometers, there was significant variability in several parameters (salinity, chl-a, snow depth and ice thickness). Analyses of the data from the arrays did not show evidence of significant patchiness at scales <20 m for algal biomass. The results imply that the sampling effort in Baltic Sea ice studies should be concentrated on scales of hundreds of meters to kilometers. Using the variations observed in the study area, the estimate for depth-integrated algal biomass in landfast sea ice in the Gulf of Finland (March 2003) is 5.5±4.4 mg chl-a m-2.  
  Address Granskog: Arctic Centre, University of Lapland, P.O. Box 122, 96101 Rovaniemi, Finland  
  Corporate Author Thesis  
  Publisher Springer-Verlag Place of Publication Heidelberg Editor  
  Language English Summary Language (down) English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0722-4060 ISBN Medium  
  Area Baltic Sea; Gulf of Finland Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Granskog++2005 Serial 739  
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Author Steffens, M.; Granskog, M.A.; Kaartokallio, H.; Kuosa, H.; Luodekari, K.; Papadimitriou, S.; Thomas, D.N. url  openurl
  Title Spatial variation of biogeochemical properties of landfast sea ice in the Gulf of Bothnia, Baltic Sea Type Conference Article
  Year 2006 Publication Annals of Glaciology Abbreviated Journal Ann Glaciol  
  Volume 44 Issue 1 Pages 80-87  
  Keywords Sea ice; Fast ice; Sea ice properties; Ice algae; Chlorophyll; Biogeochemistry; Nutrients (mineral); Particulate organic matter; Dissolved organic matter; Salinity; Spatial scale; Spatial variability; Horizontal patchiness; Sampling design; Brackish water; Ane; Baltic Sea; Gulf of Bothnia  
  Abstract Horizontal variation of landfast sea-ice properties was studied in the Gulf of Bothnia, Baltic Sea, during March 2004. In order to estimate their variability among and within different spatial levels, 72 ice cores were sampled on five spatial scales (with spacings of 10 cm, 2.5 m, 25 m, 250 m and 2.5 km) using a hierarchical sampling design. Entire cores were melted, and bulk-ice salinity, concentrations of chlorophyll a (Chl a), phaeophytin (Phaeo), dissolved nitrate plus nitrite (DIN) as well as dissolved organic carbon (DOC) and nitrogen (DON) were determined. All sampling sites were covered by a 5.5-23 cm thick layer of snow. Ice thicknesses of cores varied from 26 to 58 cm, with bulk-ice salinities ranging between 0.2 and 0.7 as is typical for Baltic Sea ice. Observed values for Chl a (range: 0.8-6.0 μg Chl a l-1; median: 2.9 μg Chl a l -1) and DOC (range: 37-397 μM; median: 95 μM) were comparable to values reported by previous sea-ice studies from the Baltic Sea. Analysis of variance among different spatial levels revealed significant differences on the 2.5 km scale for ice thickness, DOC and Phaeo (with the latter two being positively correlated with ice thickness). For salinity and Chl a, the 250 m scale was found to be the largest scale where significant differences could be detected, while snow depth only varied significantly on the 25 m scale. Variability on the 2.5 m scale contributed significantly to the total variation for ice thickness, salinity, Chl a and DIN. In the case of DON, none of the investigated levels exhibited variation that was significantly different from the considerable amount of variation found between replicate cores. Results from a principal component analysis suggest that ice thickness is one of the main elements structuring the investigated ice habitat on a large scale, while snow depth, nutrients and salinity seem to be of secondary importance.  
  Address  
  Corporate Author Thesis  
  Publisher International Glaciological Society Place of Publication Cambridge Editor  
  Language English Summary Language (down) English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0260-3055 ISBN Medium  
  Area Baltic Sea; Gulf of Bothnia Expedition Conference International Symposium on Sea Ice, Dunedin (New Zealand), 5-9 Dec 2005  
  Notes Approved no  
  Call Number refbase @ admin @ Steffens++2006 Serial 754  
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Author Thomas, D.N. url  doi
openurl 
  Title Photosynthetic microbes in freezing deserts Type Journal Article
  Year 2005 Publication Trends in Microbiology Abbreviated Journal Trends Microbiol  
  Volume 13 Issue 3 Pages 87-88  
  Keywords  
  Abstract Polar deserts are not devoid of life despite the extreme low temperature and scarcity of water. Recently, patterned stone fields – caused by periglacial activity – have been surveyed in the Arctic and Antarctic. It was found that the productivity of the cyanobacteria and algae (hypoliths) that colonise the underside of the stones is strongly related to the pattern of the stones. The hypolith assemblages were in some cases as productive as lichens, bryophytes and plants that resided nearby.  
  Address  
  Corporate Author Thesis  
  Publisher Elsevier Science B.V. Place of Publication Amsterdam Editor  
  Language English Summary Language (down) English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0966-842X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ admin @ Thomas2005 Serial 755  
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Author Underwood, G.J.C.; Aslam, S.N.; Michel, C.; Niemi, A.; Norman, L.; Meiners, K.M.; Laybourn-Parry, J.; Paterson, H.; Thomas, D.N. url  doi
openurl 
  Title Broad-scale predictability of carbohydrates and exopolymers in Antarctic and Arctic sea ice Type Journal Article
  Year 2013 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc Natl Acad Sci U S A  
  Volume 110 Issue 39 Pages 15734-15739  
  Keywords Antarctic Regions; Arctic Regions; Biopolymers/*analysis; Carbohydrates/*analysis; Ice Cover/*chemistry; Models, Chemical; Molecular Weight; Solubility; algae; biogeochemistry; global relationships; microbial  
  Abstract Sea ice can contain high concentrations of dissolved organic carbon (DOC), much of which is carbohydrate-rich extracellular polymeric substances (EPS) produced by microalgae and bacteria inhabiting the ice. Here we report the concentrations of dissolved carbohydrates (dCHO) and dissolved EPS (dEPS) in relation to algal standing stock [estimated by chlorophyll (Chl) a concentrations] in sea ice from six locations in the Southern and Arctic Oceans. Concentrations varied substantially within and between sampling sites, reflecting local ice conditions and biological content. However, combining all data revealed robust statistical relationships between dCHO concentrations and the concentrations of different dEPS fractions, Chl a, and DOC. These relationships were true for whole ice cores, bottom ice (biomass rich) sections, and colder surface ice. The distribution of dEPS was strongly correlated to algal biomass, with the highest concentrations of both dEPS and non-EPS carbohydrates in the bottom horizons of the ice. Complex EPS was more prevalent in colder surface sea ice horizons. Predictive models (validated against independent data) were derived to enable the estimation of dCHO concentrations from data on ice thickness, salinity, and vertical position in core. When Chl a data were included a higher level of prediction was obtained. The consistent patterns reflected in these relationships provide a strong basis for including estimates of regional and seasonal carbohydrate and dEPS carbon budgets in coupled physical-biogeochemical models, across different types of sea ice from both polar regions.  
  Address School of Biological Sciences, University of Essex, Colchester, Essex CO4 3SQ, United Kingdom  
  Corporate Author Thesis  
  Publisher National Academy of Sciences Place of Publication Washington, DC Editor  
  Language English Summary Language (down) English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24019487; PMCID:PMC3785782 Approved no  
  Call Number refbase @ user @ Serial 17491  
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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 (down) Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  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  
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