Now showing items 1341-1360 of 1636

    • Marine diatoms are a rich source of bioactivity 

      Ingebrigtsen, Richard Andre (Conference object; Konferansebidrag, 2014-11-03)
      As part of the MabCent-SFI drug-discovery initiative organized by the University of Tromsø, the coastal areas of northern Norway and the Barents Sea have been investigated (2006-2014). We saw that bioac- tive compounds from diatoms are very rarely reported (1-4). There- fore we desided that during the initial MabCent research cruises, di- atom strains should be isolated and kept in a culture collection ...
    • Area use and movement patterns of wild and escaped farmed Atlantic salmon before and during spawning in a large Norwegian river 

      Moe, Karina; Næsje, Tor; Haugen, Thrond Oddvar; Ulvan, Eva Marita; Aronsen, Tonje; Sandnes, Tomas; Thorstad, Eva Bonsak (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-02-02)
      We compared the within-river movements and distribution of wild and escaped farmed Atlantic salmon Salmo salar before and during spawning in the Namsen river system of Central Norway. A total of 74 wild and 43 escaped farmed salmon were captured at sea, tagged with radio transmitters and released. Based on our examinations, most, if not all salmon (farmed and wild) entering the River Namsen were ...
    • Deepened winter snow increases stem growth and alters stem δ13C and δ15N in evergreen dwarf shrub Cassiope tetragona in high-arctic Svalbard tundra 

      Blok, Daan; Weijers, Stef; Welker, Jeffrey M.; Cooper, Elisabeth J.; Michelsen, Anders; Löffler, Jörg; Elberling, Bo (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-14)
      Abstract Deeper winter snow is hypothesized to favor shrub growth and may partly explain the shrub expansion observed in many parts of the arctic during the last decades, potentially triggering biophysical feedbacks including regional warming and permafrost thawing.Weexperimentally tested the effects of winter snow depth on shrub growth and ecophysiology by measuring stem length and stem hydrogen ...
    • What are the impacts of reindeer/caribou (Rangifer tarandus L.) on arctic and alpine vegetation? A systematic review 

      Bernes, Claes; Bråthen, Kari Anne; Forbes, Bruce C.; Speed, James David Mervyn; Moen, Jon (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-02-23)
      Background: The reindeer (or caribou, Rangifer tarandus L.) has a natural range extending over much of Eurasia’s and North America’s arctic, alpine and boreal zones, yet its impact on vegetation is still unclear. This lack of a common understanding hampers both the management of wild and semi-domesticated reindeer populations and the preservation of biodiversity. To achieve a common platform, we ...
    • Deeper snow alters soil nutrient availability and leaf nutrient status in high Arctic tundra 

      Semenchuk, Philipp; Elberling, Bo; Amtorp, Cecilie; Winkler, Judith; Rumpf, Sabine Bettina; Michelsen, Anders; Cooper, Elisabeth J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-02-24)
      Nitrogen (N) mineralization, nutrient availability, and plant growth in the Arctic are often restricted by low temperatures. Predicted increases of cold-season temperatures may be important for plant nutrient availability and growth, given that N mineralization is also taking place during the cold season. Changing nutrient availability may be reflected in plant N and chlorophyll content and lead to ...
    • Future changes in the supply of goods and services from natural ecosystems: prospects for the European north 

      Jansson, Roland; Nilsson, Christer; Keskitalo, E. Carina H.; Viasova, Tatiana; Sutinen, Marja-Liisa; Moen, Jon; Chapin, Stuart; Bråthen, Kari Anne; Cabeza, Mar; Callaghan, Terry V.; van Oort, Bob; Dannevig, Halvor; Bay-Larsen, Ingrid Agathe; Ims, Rolf Anker; Aspholm, Paul Eric (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09)
      Humans depend on services provided by ecosystems, and how services are affected by climate change is increasingly studied. Few studies, however, address changes likely to affect services from seminatural ecosystems. We analyzed ecosystem goods and services in natural and seminatural systems, specifically how they are expected to change as a result of projected climate change during the 21st ...
    • Comparative absorption and tissue distribution of 14C-benzo(a)pyrene and 14C-phenanthrene in the polar cod (Boreogadus saida) following oral administration 

      Bakke, Marit Jørgensen; Nahrgang, Jasmine; Ingebrigtsen, Kristian (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-29)
      The Arctic is an important sink for organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) long-range transported from industrial regions. With the retreat of sea ice and increasing anthropogenic activities such as the oil and gas industries, local sources of PAHs are expected to increase both through operational and accidental discharges. There is a need to increase our knowledge ...
    • Cross-cultural values and management preferences in protected areas of Norway and Poland 

      Brown, Greg; Hausner, Vera Helene; Grodzińska-Jurczak, Malgorzata; Pietrzyk-Kaszyńska, Agata; Olszańska, Agnieszka; Peek, Barbara; Rechciński, Marcin; Lægreid, Eiliv Jenssen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-25)
      Protected areas provide important ecosystem services globally but few studies have examined how cultural differences influence the distribution of cultural ecosystem values and management preferences. We used internet-based public participation GIS (PPGIS) in the countries of Norway and Poland to identify ecosystem values and management preferences in protected areas held by regional residents and ...
    • Effects of land tenure and protected areas on ecosystem services and land use preferences in Norway 

      Hausner, Vera Helene; Brown, Greg; Lægreid, Eiliv Jenssen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08)
      Prior research has examined the relationship between physical landscapes and ecosystem services, but the distribution of ecosystem services by land tenure and protected areas is less developed. We analyze the spatial distribution of participatory mapped ecosystem values, as indicators of ecosystem services, to determine their relationship with land tenure in southern Norway, a region characterized ...
    • Physical landscape associations with mapped ecosystem values with implications for spatial value transfer: An empirical study from Norway 

      Brown, Greg; Hausner, Vera Helene; Lægreid, Eiliv Jenssen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-31)
      The identification of spatial associations between perceived ecosystem values and physical landscapes is confronted by a diversity of mapping methods, heterogeneous human populations, and variability in physical landscape classification systems. This study reviews previous research on spatial associations and reports new empirical findings from Norway to describe the potential for spatial “value ...
    • Aspects of reproductive biology of wild-caught polar cod (Boreogadus saida) from Svalbard waters 

      Nahrgang, Jasmine; Storhaug, Ekaterina; Murzina, Svetlana; Delmas, Olympe; Nemova, Nina N.; Berge, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-27)
      Polar cod (Boreogadus saida) is considered a key species in the Arctic marine ecosystems. Yet detailed or even basic knowledge regarding its biology and adaptations, especially during the polar night, is in many cases poor. Data are presently unavailable in Western literature on the gonad development of polar cod and its reproductive biology in wild specimens. Accordingly, gonad development of ...
    • Mixed exposure to bacterial lipopolysaccharide and seafood proteases augments inflammatory signalling in an airway epithelial cell model (A549) 

      Bhagwat, Sampada Satchidanand; Larsen, Anett Kristin; Seternes, Ole Morten; Bang, Berit (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-06)
      Seafood industry workers exhibit increased prevalence of respiratory symptoms due to exposure to bioaerosols containing a mixture of bioactive agents. In this study, a human pulmonary epithelial cell model (A549) was exposed to mixtures of bacterial lipopolysaccharide (LPS) and protease-activated receptor-2 (PAR-2) agonists H-Ser-Leu-Ile-Gly-Lys-Val-NH2 (SLIGKV-NH2), purified salmon (Salmo salar) ...
    • First records of Atlantic mackerel (Scomber scombrus) from the Svalbard archipelago, Norway, with possible explanations for the extension of its distribution 

      Berge, Jørgen; Heggland, Kristin N.; Lønne, Ole Jørgen; Cottier, Finlo R.; Hop, Haakon; Gabrielsen, Geir W.; Nøttestad, Leif; Misund, Ole Arve (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03)
      Atlantic mackerel (Scomber scombrus) were recorded in Isfjorden, Svalbard (78˚15ʹ N, 15˚11ʹ E) in late September 2013. This record is the northernmost known occurrence of mackerel in the Arctic and represents a possible northward expansion (of ca. 5˚ latitude) of its distributional range. The examined specimens of mackerel were between 7 and 11 years old, with a mean size of 39 cm and a mean ...
    • Biological introduction risks from shipping in a warming Arctic 

      Ware, Christopher; Berge, Jørgen; Jelmert, Anders; Olsen, Steffen M.; Pellisier, Loic; Wisz, Mary S.; Kriticos, Darren J.; Semenov, Georgy; Kwasniewski, Sawomir; Alsos, Inger Greve (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-12-14)
      Several decades of research on invasive marine species have yielded a broad understanding of the nature of species invasion mechanisms and associated threats globally. However, this is not true of the Arctic, a region where ongoing climatic changes may promote species invasion. Here, we evaluated risks associated with non-indigenous propagule loads discharged with ships' ballast water to the high-Arctic ...
    • The eyes of the deep diving hooded seal (Cystophora cristata) enhance sensitivity to ultraviolet light 

      Hogg, Chris; Neveu, Magella; Folkow, Lars; Stokkan, Karl-Arne; Kam, Jaimie Hoh; Douglas, Ron H; Jeffery, Glen (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-05-11)
      The mammalian visual range is approximately 400–700 nm, although recent evidence suggests varying ultraviolet (UV) extensions in diverse terrestrial species. UV sensitivity may have advantages in the dim, blue light shifted environment experienced by submerged marine mammals. It may also be advantageous when seals are on land as UV is reflected by snow and ice but absorbed by fur, enhancing visual ...
    • Extreme Features of the Galdieria sulphuraria Organellar Genomes: A Consequence of Polyextremophily? 

      Jain, Kanika; Krause, Kirsten; Grewe, Felix; Nelson, Gaven F; Weber, Andreas PM; Christensen, Alan C; Mower, Jeffrey P (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-12-13)
      Nuclear genome sequencing from extremophilic eukaryotes has revealed clues about the mechanisms of adaptation to extreme environments, but the functional consequences of extremophily on organellar genomes are unknown. To address this issue, we assembled the mitochondrial and plastid genomes from a polyextremophilic red alga, Galdieria sulphuraria strain 074 W, and performed a comparative genomic ...
    • Arctic Ocean outflow shelves in the changing Arctic: A review and perspectives 

      Michel, Christine; Hamilton, J.; Hansen, Edmond; Barber, Dave; Reigstad, Marit; Iocozza, J; Seuthe, Lena; Niemi, Andrea (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-28)
      Over the past decade or so, international research efforts, many of which were part of the International Polar Year, have accrued our understanding of the Arctic outflow shelves. The Arctic outflow shelves, namely the East Greenland Shelf (EGS) and the Canadian Arctic Archipelago (CAA), serve as conduits through which Arctic sea ice and waters and their properties are exported to the North Atlantic. ...
    • Physical constrains and productivity in the future Arctic Ocean 

      Slagstad, Dag; Wassmann, Paul; Ellingsen, Ingrid H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-20)
      Today's physical oceanography and primary and secondary production was investigated for the entire Arctic Ocean (AO) with the physical-biologically coupled SINMOD model. To obtain indications on the effect of climate change in the twenty-first century the magnitude of change, and where and when these may take place SINMOD was forced with down-scaled climate trajectories of the International Panel ...
    • Shifts in methanogenic community composition and methane fluxes along the degradation of discontinuous permafrost 

      Liebner, Susanne; Ganzert, Lars; Kiss, Andrea; Yang, Sizhong; Wagner, Dirk; Svenning, Mette Marianne (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-05-12)
      The response of methanogens to thawing permafrost is an important factor for the global greenhouse gas budget. We tracked methanogenic community structure, activity, and abundance along the degradation of sub-Arctic palsa peatland permafrost. We observed the development of pronounced methane production, release, and abundance of functional (mcrA) methanogenic gene numbers following the transitions ...
    • Macroalgal detritus and food-web subsidies along an Arctic fjord depth-gradient 

      Renaud, Paul; Løkken, Therese Smelnor; Jørgensen, Lis Lindal; Berge, Jørgen; Johnson, Beverly J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-05)
      Tight coupling between pelagic and benthic communities is accepted as a general principle on Arctic shelves. Whereas this paradigm has been useful for guiding ecological research, it has perhaps led to a disproportionate focus on POM and ice algae as the most likely sources of carbon for the benthic food web. Arctic shelves are complex systems, including banks, fjords, and trough systems up to 350 ...