Viser treff 1338-1357 av 1513

    • Structure and function of the western Baffin Bay coastal and shelf ecosystem 

      Pedro, Sara; Lemire, Mélanie; Hoover, Carie; Saint-Béat, Blanche; Janjua, Muhammad Y.; Herbig, Jennifer; Geoffroy, Maxime; Yunda-Guarin, Gustavo; Moisan, Marie-Ange; Boissinot, Justin; Tremblay, Jean-Éric; Little, Matthew; Chan, Laurie; Babin, Marcel; Kenny, Tiff-Annie; Maps, Frédéric (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-16)
      Arctic marine species, from benthos to fish and mammals, are essential for food security and sovereignty of Inuit people. Inuit food security is dependent on the availability, accessibility, quality, and sustainability of country food resources. However, climate change effects are threatening Inuit food systems through changes in abundance and nutritional quality of locally harvested species, ...
    • Structure-function relationships in the nasal cavity of Arctic and subtropical seals 

      Cheon, Hyejeong; Kjelstrup, Signe; Kizilova, Nataliya; Flekkøy, Eirik Grude; Mason, Matthew J.; Folkow, Lars (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-14)
      The heating and moistening of inhaled air, and the cooling and moisture removal from exhaled air, are crucial for the survival of animals under severe environmental conditions. Arctic mammals have evolved specific adaptive mechanisms to retain warmth and water and restrict heat loss during breathing. Here, the role of the porous turbinates of the nasal cavities of Arctic and subtropical seals is ...
    • Sub-arctic mosses and lichens show idiosyncratic responses to combinations of winter heatwaves, freezing and nitrogen deposition 

      Bokhorst, Stef; Bjerke, Jarle W.; Phoenix, Gareth K.; Jaakola, Laura; Mæhre, Hanne; Tømmervik, Hans (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-25)
      Arctic ecosystems are increasingly exposed to extreme climatic events throughout the year, which can affect species performance. Cryptogams (bryophytes and lichens) provide important ecosystem services in polar ecosystems but may be physiologically affected or killed by extreme events. Through field and laboratory manipulations, we compared physiological responses of seven dominant sub-Arctic ...
    • The Sub-Ice Algal Communities of the Barents Sea Pack Ice: Temporal and Spatial Distribution of Biomass and Species 

      Hegseth, Else Nøst; von Quillfeldt, Cecilie (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-27)
      This work summarizes ice algal studies, presented as biomass and species temporal and spatial distribution, during 11 cruises conducted between 1986 and 2012. The majority of the biomass was found as loosely attached sub-ice algal layers, and sampling required diving. A maximum of 40 mg chlorophyll m<sup>−2</sup> and 15.4 × 10<sup>9</sup> cells m<sup>−2</sup> was measured in May. The species ...
    • Summer and winter MgCO3 levels in the skeletons of Arctic bryozoans 

      Iglikowska, Anna; Krzemińska, Małgorzata; Renaud, Paul Eric; Berge, Jørgen; Hop, Haakon; Kuklinski, Piotr (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-02)
      <p>In the Arctic, seasonal patterns in seawater biochemical conditions are shaped by physical, chemical, and biological processes related to the alternation of seasons, i.e. winter polar night and summer midnight sun. In summertime, CO<sub>2</sub> concentration is driven by photosynthetic activity of autotrophs which raises seawater pH and carbonate saturation state (Ω). In addition, restriction of ...
    • Superb Winter fur insulation in small Siberian musk deer (Moschus moschiferus) 

      Blix, Arnoldus S; Kvadsheim, Petter Helgevold; Kholodova, Marina V.; Sokolov, Vladimir E.; Messelt, Edward B.; Tyler, N. J. C. (Journal article; Tidsskriftartikkel, 2015)
    • Surface aggregations of Calanus finmarchicus during the polar night 

      Espinasse, Boris Dristan; Daase, Malin; Halvorsen, Elisabeth; Reigstad, Marit; Berge, Jørgen; Basedow, Sünnje Linnéa (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-16)
      While marine ecosystems in polar areas were thought to be mostly inactive during the polar night, recent observations in the Arctic highlight that dynamic biological interactions occur across all trophic levels. One particularly interesting observation made repeatedly is the occurrence of Calanus finmarchicus, a key species at the base of the food web, in the upper part of the water column in early ...
    • Surface chlorophyll anomalies induced by mesoscale eddy- wind interactions in the northern Norwegian Sea 

      Dong, Huizi; Zhou, Meng; Raj, Roshin Pappukutty; Smith, Walker O; Basedow, Sünnje Linnéa; Ji, Rubao; Ashjian, Carin; Zhang, Zhaoru; Hu, Ziyuan (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-29)
      The substantial productivity of the northern Norwegian Sea is closely related to its strong mesoscale eddy activity, but how eddies affect phytoplankton biomass levels in the upper ocean through horizontal and vertical transportmixing has not been well quantified. To assess mesoscale eddy induced ocean surface chlorophyll-a concentration (CHL) anomalies and modulation of eddywind interactions in ...
    • Susceptibility of polar cod (Boreogadus saida) to a model carcinogen 

      Lerebours, Adélaïde; Murzina, Svetlana; Song, You; Tollefsen, Knut-Erik; Benedetti, Maura; Regoli, Francesco; Rotchell, Jeanette M.; Nahrgang, Jasmine (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-27)
      Studies that aim to characterise the susceptibility of the ecologically relevant and non-model fish polar cod (Boreogadus saida) to model carcinogens are required. Polar cod were exposed under laboratory conditions for six months to control, 0.03 μg BaP/g fish/week and 0.3 μg BaP/g fish/week dietary benzo(a)pyrene (BaP), a reference carcinogen. The concentrations of the 3-OH-BaP bile metabolite and ...
    • Sustainable blue foods: drivers and barriers in northern Norway 

      Kebir, Zina Asnah; Abu-Alam, Tamer; Schøning, Lena; Hausner, Vera Helene; Weber, Charlotte Teresa; Iordan, Cristina Maria; Engen, Sigrid (Research report; Forskningsrapport, 2023)
      There is a push for transition to sustainable blue food systems in the High North. An interdisciplinary group of Fram Centre researchers have looked closer at the drivers motivating the transition and identified a set of barriers to sustainable blue food systems in northern Norway.
    • Sustainable management of populations impacted by harvesting and climate change 

      Stenseth, Nils Christian; Ims, Rolf Anker; Sæther, Bernt-Erik; Cadahia, Luis; Herfindal, Ivar; Lee, Aline Magdalena; Whittington, Jason D; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-13)
      The sustainable use of natural resources is critical for addressing the global challenges of today. Strategies for sustainable harvesting need to consider not only harvested species, but also other non-harvested species interacting with them in the same ecosystem. In addition, environmental variation needs to be considered, with climate change currently being one of the main sources of this ...
    • Sustainable strategies for harvesting predators and prey in a fluctuating environment 

      Bellier, Edwige; Sæther, Bernt-Erik; Engen, Steinar (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-12)
      The effects of harvest and fluctuating environment on inter-dependent predators and prey are complex and not well-known. We define a stochastic model where the predators and prey dynamically interact. The novelty of the model holds on the fact that predators and prey dynamics are simultaneously affected by correlated environmental noises. Interacting predators and prey are harvested using a proportional ...
    • Svalbard reindeer winter diets: Long-term dietary shifts to graminoids in response to a changing climate 

      Hiltunen, Tamara A.; Stien, Audun; Väisänen, Maria; Ropstad, Erik; Aspi, Jouni O.; Welker, Jeffery M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-07)
      Arctic ecosystems are changing dramatically with warmer and wetter conditions resulting in complex interactions between herbivores and their forage. We investigated how Svalbard reindeer (Rangifer tarandus platyrhynchus) modify their late winter diets in response to long-term trends and interannual variation in forage availability and accessibility. By reconstructing their diets and foraging ...
    • Swimming performance of subarctic Calanus spp. facing downward currents 

      Weidberg, Nicholas; DiBacco, Claudio; Pezzola, Caterina; Rebiffe, Etienne; Basedow, Sünnje Linnéa (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-29)
      Calanoid copepods dominate mesozooplankton communities in temperate and Nordic seas. The ability of copepods to remain and feed in productive surface waters depends on their ability to overcome downward flows. In this study, we assessed the swimming performance of subarctic Calanus spp. and tested how the copepods can retain their vertical position in a representative range of downward currents ...
    • Sympagic fauna in and under Arctic pack ice in the annual sea ice system of the new Arctic Frontiers in Marine Science 

      Ehrlich, Julia; Schaafsma, Fokje L.; Bluhm, Bodil; Peeken, Ilka; Castellani, Guilia; Brandt, Angelika; Flores, Hauke (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-19)
      A strong decline and thinning of the Arctic sea-ice cover over the past five decades has been documented. The former multiyear sea-ice system has largely changed to an annual system and with it the dynamics of sea-ice transport across the Arctic Ocean. Less sea ice is reaching the Fram Strait and more ice and ice-transported material is released in the northern Laptev Sea and the central Arctic ...
    • Sympatric diversification as influenced by ecological opportunity and historical contingency in a young species lineage of whitefish 

      Siwertsson, Anna; Knudsen, Rune; Kahilainen, Kimmo; Præbel, Kim; Primicerio, Raul; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2010)
      In adaptive radiations, ecological opportunity (i.e. niche availability) is considered to be an important driver to increase phenotypic variation, but diversity may also be constrained by historical factors related to colonization events. How do ecological opportunity and post-glacial colonization history affect the phenotypic diversity in a young species lineage? We quantified phenotypic diversity ...
    • Synchronous timing of return to breedingsites in a long-distance migratory seabirdwith ocean-scale variation in migrationschedules 

      van Bemmelen, Rob S.A.; Moe, Børge; Schekkerman, Hans; Hanssen, Sveinn Are; Snell, Katherine R. S.; Humphreys, Elizabeth M.; Mäntylä, Elina; Hallgrimsson, Gunnar Thor; Gilg, Olivier; Ehrich, Dorothee; Calladine, John; Hammer, Sjúrður; Harris, Sarah; Lang, Johannes; Vignisson, Sölvi Rúnar; Kolbeinsson, Yann; Nuotio, Kimmo; Sillanpää, Matti; Sittler, Benoit; Sokolov, Aleksandr; Klaassen, Raymond H. G.; Phillips, Richard A.; Tulp, Ingrid (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-22)
      Background Migratory birds generally have tightly scheduled annual cycles, in which delays can have carry-over effects on the timing of later events, ultimately impacting reproductive output. Whether temporal carry-over effects are more pronounced among migrations over larger distances, with tighter schedules, is a largely unexplored question. <p><p>Methods We tracked individual Arctic Skuas ...
    • Synechococcus in the Atlantic Gateway to the Arctic Ocean 

      Paulsen, Maria Lund; Doré, Hugo; Garczarek, Laurence; Seuthe, Lena; Müller, Oliver; Sandaa, Ruth-Anne; Bratbak, Gunnar; Larsen, Aud (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-10-05)
      Increasing temperatures, with pronounced effects at high latitudes, have raised questions about potential changes in species composition, as well as possible increased importance of small-celled phytoplankton in marine systems. In this study, we mapped out one of the smallest and globally most widespread primary producers, the picocyanobacterium Synechococcus, within the Atlantic inflow to ...
    • Synergism between cruising cod and ambush sculpin predators on 0-group gadoids is modified by daylight cycle and presence of aggressive wolffish 

      Strand, Hans Kristian; Pedersen, Torstein; Christie, Hartvig C; Moy, Frithjof Emil (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-06)
      Shorthorn sculpin (<i>Myoxocephalus scorpius</i>) and large cod (300–400 g body weight) are important predators on newly settled 0-group cod (<i>Gadus morhua</i>) and saithe (<i>Pollachius virens</i>) in Porsangerfjorden in northern Norway. The Atlantic wolffish (<i>Anarhichas lupus</i>) used to be abundant but is now very rare in the fjord. Video recorded experiments showed that interactions between ...
    • A synoptic history of the development, production and environmental oversight of hydropower in Brazil, Canada, and Norway 

      Alfredsen, K.; Amundsen, P.-A.; Hahn, L.; Harrison, P.M.; Helland, Ingeborg Palm; Martins, E.G.; Twardek, W.M.; Power, M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-17)
      Sustainable global energy production is back-stopped by hydropower which is responsible for a significant share of the green energy produced worldwide. Hydropower, however, does not come without some environmental impacts but has worked to reduce those impacts. Here, we discuss the historical, legislative, and design configurations of hydropower facilities located in three of the world’s ...