Polar Research (E-Journal)
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Review of Inuit and whalers on Baffin Island through German eyes. Wilhelm Weike’s Arctic journal and letters (1883-84), by Ludger Müller-Wille & Bernd Gieseking
No full textIn 1883, Wilhelm Weike set off from Germany to spend a year on Baffin Island. He would probably have remained unknown if it had not been for the fact that he was the servant of the young and later well-known scientist, Franz Boas, on his expedition to Baffin Island in 1883-84. As part of his work, Boas made Weike keep a journal in order to supplement his own notes. Weike did this, although not always with great length or detail. The journal was published in German in 2008 to celebrate the International Polar Year and is now available to a larger audience in English.(Published: 18 December 2012)Citation: Polar Research 2012, 31, 20122, http://dx.doi.org/10.3402/polar.v31i0.2012
Review of Science in the snow: fifty years of international collaboration through the Scientific Committee on Antarctic Research, by David W.H. Walton & Peter D. Clarkson
No full textD. Walton and P. Clarkson present a history of the last 50 years of international collaborations stimulated by the presence and flexibility inherent in the Scientific Committee on Antarctic Research (SCAR) in their new book Science in the snow. As aptly portrayed in the acknowledgements that precede the book, SCAR has been both an important umbrella for drawing attention to the Antarctic and a virtual and real (meeting rooms to pubs) venue for Antarctic scientists to discuss their scientific findings, their experiences, and their dreams for understanding a place that - with the exception of the impact of iconic expeditions of the early explorers - was barely on the world’s collective mind until about 50 years ago.(Published: 3 September 2012)Citation: Polar Research 2012, 31, 19275, http://dx.doi.org/10.3402/polar.v31i0.1927
High-temperature optima phosphatases from the cold-tolerant Arctic fungus Penicillium citrinum
No full textFifty-six fungal isolates from Arctic soils were subjected to primary screening for their ability to solubilize insoluble inorganic phosphate. Nine of the isolates were further analysed quantitatively for phosphatase production using para-nitrophenylphosphate as substrate. Amongst these, a cold-tolerant fungus, Penicillium citrinum strain PG162 was found to be the best producer of intracellular acid phosphatase. Further characterization of the enzyme showed that it is most active in the temperature range of 40-60°C and pH range of 4.2-4.8. The dried enzyme extract is stable at a temperature of up to 50°C for at least 1 h. Its activity is affected by presence of metal ions. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE) analysis suggests the molecular weight of the enzyme to be between 20 and 29 kDa. The present study is important with respect to our understanding of the kind of enzymatic reactions that take place in the polar microbes, and the extent to which their activity is sustained.Keywords: acid phosphatase; enzyme; para-nitrophenylphosphate; Pikovskaya medium; psychrotolerant; SDSPAGE(Published: 9 August 2012)Citation: Polar Research 2012, 31, 11105, http://dx.doi.org/10.3402/polar.v31i0.1110
The sublittoral macroflora of Hornsund
No full textCombined hydroacoustic, video and direct examination by scuba-diving of the underwater meadows of Hornsund, a flagship biodiversity site in Svalbard, revealed 17 species of macroalgae with a biomass, dominated by Laminariales, of as much as 3 kg m-2. The biomass dominants were Laminaria digitata and Saccharina latissima, which were most abundant at depths of between 5 and 10 m. The species data presented are the first records for the fjord and provide a starting point for new research and a baseline for future assessments of climate-induced changes.Keywords: Macroalgae; Hornsund; Arctic fjord; West Spitsbergen; laminariales(Published: 18 July 2012)Citation: Polar Research 2012, 31, 18900, http://dx.doi.org/10.3402/polar.v31i0.1890
Low genetic diversity in Antarctic populations of the lichenforming ascomycete Cetraria aculeata and its photobiont
No full textLichens, symbiotic associations of fungi (mycobionts) and green algae or cyanobacteria (photobionts), are poikilohydric organisms that are particularly well adapted to withstand adverse environmental conditions. Terrestrial ecosystems of the Antarctic are therefore largely dominated by lichens. The effects of global climate change are especially pronounced in the maritime Antarctic and it may be assumed that the lichen vegetation will profoundly change in the future. The genetic diversity of populations is closely correlated to their ability to adapt to changing environmental conditions and to their future evolutionary potential. In this study, we present evidence for low genetic diversity in Antarctic mycobiont and photobiont populations of the widespread lichen Cetraria aculeata. We compared between 110 and 219 DNA sequences from each of three gene loci for each symbiont. A total of 222 individuals from three Antarctic and nine antiboreal, temperate and Arctic populations were investigated. The mycobiont diversity is highest in Arctic populations, while the photobionts are most diverse in temperate regions. Photobiont diversity decreases significantly towards the Antarctic but less markedly towards the Arctic, indicating that ecological factors play a minor role in determining the diversity of Antarctic photobiont populations. Richness estimators calculated for the four geographical regions suggest that the low genetic diversity of Antarctic populations is not a sampling artefact. Cetraria aculeata appears to have diversified in the Arctic and subsequently expanded its range into the Southern Hemisphere. The reduced genetic diversity in the Antarctic is most likely due to founder effects during long-distance colonization. The environmental conditions of the Antarctic are among the most adverse on Earth and are generally characterized by low mean annual temperatures, high wind velocities, extreme drought and extended periods of darkness. The effects of global climate change are especially pronounced in parts of the Antarctic (Turner et al. 2005). Air temperature in the maritime Antarctic has steadily increased within the last years (Smith & Stammerjohn 1996; Turner et al. 2005). On the western Antarctic Peninsula a temperature increase of more than 2.5 K has been observed over the last 50 years. The overall effect of such a temperature increase on terrestrial Antarctic organisms could be beneficial. For example, glacial melting will increase the availability of terrestrial (page number not for citation purpose)Keywords Genetic diversity; lichens; Cetraria aculeata; Trebouxia jamesii; polar lichens; global change(Published: 27 March 2012)Citation: Polar Research 2012, 31, 17353, DOI: 10.3402/polar.v31i0.17353To access the supplementary material to this article 'Supplementar tables 6-8' please see Supplementary files in the column to the right (under Article Tools
Chemical constituents and antioxidant activity of the Arctic mushroom Lycoperdon molle Pers
No full textThe biochemical adaptations of fungi to the harsh conditions of the Arctic may mean that these organisms have properties useful to people. Using samples of the puffball mushroom Lycoperdon molle Pers. (Basidiomycota, Fungi) collected at Ny-Ålesund, Svalbard, we examined the in vitro antioxidant potential of this species by investigating its free-radical scavenging (FRS) activity, inhibition of lipid peroxidation (ILP) and Trolox equivalent antioxidant capacity (TEAC). The FRS activity of the samples in various organic solvents, including methanol, ethanol, acetone and dimethyl sulfoxide (DMSO), were found to be in the range of 44.00-89.60%, while ILP activities ranged from 32.00 to 54.41%. The methanol extract showed the highest levels of FRS (89.60%) and ILP (54.41%) compared to standard antioxidants butylated hydroxyanisol and butylated hydroxytoluene (BHT). The TEAC value was also found to be higher compared to the standard water soluble vitamin E analogue Trolox (3.9 mM). Antimicrobial screening of Lycoperdon molle extracts was negative to the tested microorganisms. Using electrospray ionization mass spectrometry (ESI-MS), we determined that the samples contained compounds such as phosphoethanolamine, monomethyl arsenic acid, phosphatidyl glycerol, phosphoionositol, phosphoserine and lysophosphatidyl choline. We found that Lycoperdon molle showed strong antioxidant abilities compared to the standards, suggesting that this and perhaps other Arctic mushrooms could be valuable sources of natural antioxidants for the pharmaceutical industry. To our knowledge, this is the first report of the antioxidant activity in any Arctic mushroom.Keywords: Lycoperdon; fungi; antioxidative potential; HPLC; ESI-MS; Arctic(Published: 12 March 2012)Citation: Polar Research 2012, 31, 17329, DOI: 10.3402/polar.v31i0.1732
Foreword: The complex business of managing human activities and protecting the environment of the polar regions
No full textThe thematic cluster ‘‘Human impacts in the Arctic and Antarctic’’ in Polar Research has its origins in the International Polar Year (2007-09) Oslo Science Conference held in Oslo, Norway, from 8 to 12 June 2010. We were the co-convenors of the session ‘‘Human impacts in the Arctic and Antarctic: regulatory and management implications,’’ in which 27 talks and 21 posters were presented over the course of two days. We invited contributors to the conference session to explore all types of impacts of human activities and regional environmental change in the polar regions, with a special focus on highlighting the management priorities for the protection of the landscape (environment and people) of the polar regions in the face of increasing human activity. Exploring a wide range of topics ranging from human wildlife interactions to chemical contamination and from whaling to polar tourism, contributors provided examples of existing environmental management regimes that are working as well as those that are not.(Published: 28 December 2012)Citation: Polar Research 2012, 31, 20228, http://dx.doi.org/10.3402/polar.v31i0.2022
Review of Race for the South Pole: the expedition diaries of Scott and Amundsen, by Roland Huntford
No full textRoland Huntford is the grand old man among polar historians. After his classic Scott and Amundsen in 1979 (later editions were retitled, The last place on Earth), he wrote a series of books on Norwegian and British polar heroes as well as a thorough study of the history of skiing (2006). Huntford challenged the British admiration of Robert Falcon Scott’s scientific programme and great courage*and insisted that Roald Amundsen’s expedition was far better prepared and carried out. Huntford’s scathing criticism of Scott’s fatal choices and lack of competence dared to assault this cherished British polar icon in a manner that would be unthinkable for Norwegian authors.(Published: 7 June 2012)Citation: Polar Research 2012, 31, 18741, http://dx.doi.org/10.3402/polar.v31i0.1874
Aspartic acid racemization rate in narwhal (Monodon monoceros) eye lens nuclei estimated by counting of growth layers in tusks
No full textAges of marine mammals have traditionally been estimated by counting dentinal growth layers in teeth. However, this method is difficult to use on narwhals (Monodon monoceros) because of their special tooth structures. Alternative methods are therefore needed. The aspartic acid racemization (AAR) technique has been used in age estimation studies of cetaceans, including narwhals. The purpose of this study was to estimate a species-specific racemization rate for narwhals by regressing aspartic acid D/L ratios in eye lens nuclei against growth layer groups in tusks (n=9). Two racemization rates were estimated: one by linear regression (r2=0.98) based on the assumption that age was known without error, and one based on a bootstrap study, taking into account the uncertainty in the age estimation (r2 between 0.88 and 0.98). The two estimated 2kAsp values were identical up to two significant figures. The 2kAsp value from the bootstrap study was found to be 0.00229±0.000089 SE, which corresponds to a racemization rate of 0.00114-yr±0.000044 SE. The intercept of 0.0580±0.00185 SE corresponds to twice the (D/L)0 value, which is then 0.0290±0.00093 SE. We propose that this species-specific racemization rate and (D/L)0 value be used in future AAR age estimation studies of narwhals, but also recommend the collection of tusks and eyes of narwhals for further improving the (D/L)0 and 2kAsp estimates obtained in this study.Keywords: Age estimation; Greenland; species-specific racemization rate; growth layers groups(Published: 21 November 2012)Citation: Polar Research 2012, 31, 15865, http://dx.doi.org/10.3402/polar.v31i0.1586
The effectiveness of the Arctic Council
No full textCreated in 1996, the Arctic Council has now been in operation long enough to justify a systematic effort to assess its effectiveness. To explore this topic, we created a questionnaire and circulated it to a large number of individuals who have participated in the work of the council in one capacity or another or who have followed the work of the council closely. This article analyses the quantitative and the qualitative input of those who responded to the questionnaire. The main conclusions are that: the council has achieved considerable success in identifying emerging issues, framing them for consideration in policy venues and raising their visibility on the policy agenda and changes now occurring in the Arctic will require significant adjustments to maintain the effectiveness of the council during the foreseeable future.Keywords: Arctic Council; governance; Arctic Monitoring and Assessment Programme; Conservation of Arctic Flora and Fauna; Protection of the Arctic Marine Environment; Sustainable Development Working Group(Published: 26 October 2012)Citation: Polar Research 2012, 31, 17176, http://dx.doi.org/10.3402/polar.v31i0.1717