Ole Arve Misund

Polar Research, Год журнала: 2017, Номер 36, С. 1 - 10

Опубликована Апрель 25, 2017

Svalbard, a High-Arctic archipelago over which Norway practises sovereignty in accordance with the terms of the Svalbard Treaty, has become an increasingly important area for Arctic research and higher education. There are four more or less permanent settlements with substantial research infrastructure, and a few manned observatories for special purposes. Several Norwegian and foreign research institutions have established stations and installations in the archipelago. With coal mining activity scaling down because of economic difficulties and lack of political support for subsidies, Norwegian policy will prioritize research and higher education as a way of maintaining Norwegian settlements in Svalbard. I give …

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Christian Lydersen,

Kit M. Kovacs,

Jade Vaquie-Garcia,

Espen Lydersen,

Guttorm N. Christensen

Polar Research, Год журнала: 2017, Номер 36, С. 1 - 12

Опубликована Окт. 6, 2017

Ringed seals (Pusa hispida) are the most ice-associated of all Arctic pinnipeds. In the Svalbard area, this species has always given birth, moulted and rested on sea ice. In addition, much of their food has been comprised of ice-associated prey. Recently, ringed seals have been reported to be using terrestrial substrates as a haul-out platform in some fjords on the west coast of Spitsbergen. In many cases the seals involved are harbour seals (Phoca vitulina), which are extending their distribution into new areas within the Svalbard Archipelago and which are being misclassified as ringed seals. However, this study reports that …

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Catherine L. Docherty,

Tenna Riis,

David M. Hannah,

Simon Rosenhøj Leth,

Alexander M. Milner

Polar Research, Год журнала: 2018, Номер 37, С. 1 - 7

Опубликована Март 19, 2018

Permafrost thaw induced by climate change will cause increased release of nutrients and organic matter from the active layer to Arctic streams and, with increased water temperature, will potentially enhance algal biomass and nutrient uptake. Although essential for accurately predicting the response of Arctic streams to environmental change, knowledge of nutrient release on current Arctic in-stream processing is limited. Addressing this research gap, we quantified nutrient uptake of short-term releases of NO 3− , PO 43- and NH 4+ during peak snowmelt season in five streams of contrasting physiochemical characteristics (from unstable, highly turbid to highly stable, clear-water systems) in …

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Agnieszka Promińska,

Waldemar Walczowski,

Eva Falck

Polar Research, Год журнала: 2018, Номер 37, С. 1 - 12

Опубликована Сен. 6, 2018

Progressing warming in the Arctic and increased extreme weather events can significantly influence the hydrography of Svalbard fjords, leading to changes towards more Atlantic-type waters in the fjords. In this paper, we look into the hydrographic conditions in Hornsund, the southernmost fjord on the west coast of Svalbard, by analysing high-resolution CTD measurements collected in July during cruises with the RV Oceania between 2001 and 2015. These observations revealed high interannual variability in temperature, salinity and distribution of water masses, mainly due to differences in timing of the transition between winter and summer conditions but also as a result of …

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Luidmila A. Pestryakova,

Ulrike Herzschuh,

Ruslan Gorodnichev,

Sebastian Wetterich

Polar Research, Год журнала: 2018, Номер 37, С. 1 - 12

Опубликована Июль 31, 2018

Relative abundances of 157 diatom taxa from Yakutian lake surface-sediments were investigated for their potential to indicate certain environmental conditions. Data from 206 sites from Arctic, sub-Arctic and boreal environments were included. Redundancy analyses were performed to assess the explanatory power of mean July temperature (T July ), conductivity, pH, dissolved silica concentration, phosphate concentration, lake depth and vegetation type on diatom species composition. Boosted regression tree analyses were performed to infer the most relevant environmental variables for abundances of individual taxa and weighted average regression was applied to infer their respective optimum and tolerance. Electrical conductivity was best indicated …

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Pooja Kashid

Создана Авг. 7, 2023

Unlocking the Potential: Online platforms have revolutionized UPSC preparation, offering abundant quality content, personalized mentorship, and unparalleled flexibility. With RAUIAS as a prime example, aspirants now have access to top-notch resources and guidance to achieve their dreams of serving the nation.

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Jenny Maccali,

Claude Hillaire-Marcel,

Christelle Not

Polar Research, Год журнала: 2018, Номер 37, С. 1 - 10

Опубликована Март 22, 2018

Under modern conditions, sediments from the large continental shelves of the Arctic Ocean are mixed by currents, incorporated into sea ice and redistributed over the Arctic Basin through the Beaufort Gyre and Trans-Polar Drift major sea-ice routes. Here, compiling data from the literature and combining them with our own data, we explore how radiogenic isotopes (Sr, Pb and Nd) from Arctic shelf surface sediment can be used to identify inland and coastal sediment sources. Based on discriminant function analyses, the use of two-isotope systematics introduces a large uncertainty (ca. 50%) that prevents unequivocal identifications of regional shelf signatures. However, when …

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Luke Storrie,

Christian Lydersen,

Magnus Andersen,

Russell B. Wynn,

Kit M. Kovacs

Polar Research, Год журнала: 2018, Номер 37, С. 1 - 12

Опубликована Июнь 1, 2018

This study used 13 years of cetacean sighting data (2002–2014) from waters around the Svalbard Archipelago to determine key habitats for year-round resident species as well as seasonally resident species, and to explore spatial overlap between these groups via a combination of kernel density estimation and Maxent modelling. The data set consists of observations made by research vessels conducting various marine studies, coast guard ships and marine-cruise tourist operators. Data are reported from the seasonal period in which there is daylight (March-November), though 95% of the observations occurred June- September. Changes over the study period were investigated, within the limits …

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Karen Lone,

Jon Aars,

Christian Lydersen,

Kit M. Kovacs,

Charmain D. Hamilton

Polar Research, Год журнала: 2019, Номер 38, С. 1 - 15

Опубликована Сен. 13, 2019

Ringed seals are a central component of the Arctic ecosystem; they have a circumpolar distribution and are both important predators of lower trophic animals (invertebrates and fishes) and prey for polar bears and coastal human populations. They depend on sea ice for reproduction, moulting and resting, and they consume significant amounts of ice-associated prey. The population of ringed seals in Svalbard, Norway, uses both coastal and offshore habitats, the latter being important during seasonal migrations undertaken by some animals, mostly juveniles. This study examined habitat preferences of 18 satellite-tracked ringed seals (mostly young animals, but also a few adults) during …

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Morten Frederiksen,

Jannie F. Linnebjerg,

Flemming R. Merkel,

Sabina I. Wilhelm,

Gregory J. Robertson

Polar Research, Год журнала: 2019, Номер 38, С. 1 - 12

Опубликована Авг. 6, 2019

Brünnich’s guillemot (Uria lomvia), or thick-billed murre, is an abundant pan-Arctic seabird, but several Atlantic breeding populations are declining. The species is subject to traditional harvest in the important wintering areas off west Greenland and Newfoundland, and has been subject to chronic oil pollution on the east coast of Canada. Until recently, knowledge of winter distribution has been insufficient to assess the impact of these mortality sources on specific breeding populations. We collate existing information on mortality from bag statistics in Greenland and Canada and studies of oiling off Newfoundland, as well as new data on age distribution in the …

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