Now showing items 1001-1020 of 1643

    • A rapid preparation procedure for laser microdissection‑mediated harvest of plant tissues for gene expression analysis 

      Olsen, Stian; Krause, Kirsten (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-02)
      <p><i>Background - </i>Gene expression changes that govern essential biological processes can occur at the cell-specific level. To gain insight into such events, laser microdissection is applied to cut out specific cells or tissues from which RNA for gene expression analysis is isolated. However, the preparation of plant tissue sections for laser microdissection and subsequent RNA isolation usually ...
    • Incomplete degradation of lichen usnic acid and atranorin in Svalbard reindeer (Rangifer tarandus platyrhynchus) 

      Węgrzyn, Michał Hubert; Wietrzyk-Pełka, Paulina; Galanty, Agnieszka; Cykowska-Marzencka, Beata; Sundset, Monica Alterskjær (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-22)
      Previous studies of Eurasian tundra reindeer (<i>Rangifer tarandus tarandus</i>) in Norway indicate that their rumen microbiota play a key role in degrading lichen secondary metabolites. We investigated the presence of usnic acid and atranorin in faecal samples from Svalbard reindeer (<i>R. tarandus platyrhynchus</i>). Samples were collected in Bolterdalen valley together with vegetation samples ...
    • Seasonal dynamics of the marine CO2 system in Adventfjorden, a West Spitsbergen fjord 

      Ericson, Ylva; Chierici, Melissa; Falck, Eva; Fransson, Agneta Ingrid; Jones, Elizabeth Marie; Kristiansen, Svein (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-11)
      Time series of the marine CO<sub>2</sub> system and related parameters at the IsA Station, by Adventfjorden, Svalbard, were investigated between March 2015 and November 2017. The physical and biogeochemical processes that govern changes in total alkalinity (TA), total dissolved inorganic carbon (DIC) and the saturation state of the calcium carbonate mineral aragonite (Ω<sub>Ar</sub>) were assessed ...
    • Drones as a tool to monitor human impacts and vegetation changes in parks and protected areas 

      Ancin-Murguzur, Francisco Javier; Munoz, Lorena; Monz, Christopher; Hausner, Vera H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-04)
      Increased visitation to protected areas could have adverse impacts on the conservation values in the protected areas, and therefore effective visitor monitoring methods are needed to meet the complex management challenges that arise. Collecting data on human impacts is highly time consuming, thus requiring more effective tools that allow for high-quality and long-term measurements. In this study, ...
    • Advection of Mesozooplankton Into the Northern Svalbard Shelf Region 

      Wassmann, Paul; Slagstad, Dag; Ellingsen, Ingrid H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-14)
      The northern Svalbard shelf region is part of the Atlantic advective contiguous domain along which nutrients, phyto- and mesozooplankton are advected with Atlantic Water from the Norwegian Sea along the Norwegian shelf break and into the Arctic Ocean. By applying the SINMOD model, we investigated how much mesozooplankton may be advected into the northern Svalbard shelf region. We also compared this ...
    • Tidewater glaciers and bedrock characteristics control the phytoplankton growth environment in a fjord in the arctic 

      Halbach, Laura; Vihtakari, Mikko; Duarte, Pedro; Everett, Alistair; Granskog, Mats; Hop, Haakon; Kauko, Hanna Maria; Kristiansen, Svein; Myhre, Per Inge; Pavlov, Alexey K.; Pramanik, Ankit; Tatarek, Agnieszka; Torsvik, Tomas; Wiktor, Józef Maria; Wold, Anette; Wulff, Angela; Steen, Harald; Assmy, Philipp (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-05-31)
      Meltwater discharge from tidewater glaciers impacts the adjacent marine environment. Due to the global warming, tidewater glaciers are retreating and will eventually terminate on land. Yet, the mechanisms through which meltwater runoff and subglacial discharge from tidewater glaciers influence marine primary production remain poorly understood, as data in close proximity to glacier fronts are scarce. ...
    • A glimpse into the biogeography, seasonality, and ecological functions of arctic marine Oomycota 

      Hassett, Brandon Thomas; Thines, Marco; Buaya, Anthony; Ploch, Sebastian; Gradinger, R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-20)
      High-latitude environments are warming, leading to changes in biological diversity patterns of taxa. <i>Oomycota</i> are a group of fungal-like organisms that comprise a major clade of eukaryotic life and are parasites of fish, agricultural crops, and algae. The diversity, functionality, and distribution of these organisms are essentially unknown in the Arctic marine environment. Thus, it was our ...
    • A way forward with eco evo devo: an extended theory of resource polymorphism with postglacial fishes as model systems 

      Skulason, Skuli; Parsons, Kevin J; Svanback, Richard; Räsänen, Katja; Ferguson, Moira M; Adams, Colin Ean; Amundsen, Per-Arne; Bartels, Pia; Bean, Colin W.; Boughman, Janette W.; Englund, Göran; Gudbrandsson, Johannes; Hooker, Oliver E.; Hudson, Alan G; Kahilainen, Kimmo Kalevi; Knudsen, Rune; Kristjánsson, Bjarni Kr.; Leblanc, Camille A-L; Jonsson, Zophonias; Ohlund, Gunnar; Smith, Carl; Snorrason, Sigurdur S (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-19)
      A major goal of evolutionary science is to understand how biological diversity is generated and altered. Despite considerable advances, we still have limited insight into how phenotypic variation arises and is sorted by natural selection. Here we argue that an integrated view, which merges ecology, evolution and developmental biology (eco evo devo) on an equal footing, is needed to understand the ...
    • Zooplankton communities associated with new and regenerated primary production in the Atlantic inflow north of Svalbard 

      Svensen, Camilla; Halvorsen, Elisabeth; Vernet, Maria; Franzè, Gayantonia; Dmoch, Katarzyna; Lavrentyev, Peter J.; Kwasniewski, Slawomir (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-05)
      The Arctic Ocean is changing rapidly with respect to ice cover extent and volume, growth season duration and biological production. Zooplankton are important components in the arctic marine food web, and tightly coupled to the strong seasonality in primary production. In this study, we investigate zooplankton composition, including microzooplankton, copepod nauplii, as well as small and large copepod ...
    • Documenting lemming population change in the Arctic: Can we detect trends? 

      Ehrich, Dorothée; Schmidt, Niels M.; Gauthier, Gilles; Alisauskas, Ray; Angerbjörn, Anders; Clark, Karin; Ecke, Frauke; Eide, Nina E.; Framstad, Erik; Frandsen, Jay; Franke, Alastair; Gilg, Olivier; Giroux, Marie-Andrée; Henttonen, Heikki; Hörnfeldt, Birger; Ims, Rolf A.; Kataev, Gennadiy D.; Kharitonov, Sergey P.; Killengreen, Siw T.; Krebs, Charles J.; Lanctot, Richard B.; Lecomte, Nicolas; Menyushina, Irina E.; Morris, Douglas W.; Morrisson, Guy; Oksanen, Lauri; Oksanen, Tarja; Olofsson, Johan; Pokrovsky, Ivan G.; Yu, Igor; Reid, Donald; Roth, James D.; Saalfeld, Sarah T.; Samelius, Gustaf; Sittler, Benoit; Sleptsov, Sergey M.; Smith, Paul A.; Sokolov, Alekstandr A.; Sokolova, Natalya A.; Soloviev, Mikhail Y.; Solovyeva, Diana V. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-22)
      Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed ...
    • Alien plants, animals, fungi and algae in Norway: an inventory of neobiota 

      Sandvik, Hanno; Dolmen, Dag; Elven, Reidar; Falkenhaug, Tone; Forsgren, Elisabet; Hansen, Haakon; Hassel, Kristian; Husa, Vivian; Kjærstad, Gaute; Ødegaard, Frode; Pedersen, Hans Christian; Solheim, Halvor; Stokke, Bård Gunnar; Åsen, Per Arvid; Åström, Sandra Charlotte Helene; Brandrud, Tor Erik; Elven, Hallvard; Endrestøl, Anders; Finstad, Anders Gravbrøt; Fredriksen, Stein; Gammelmo, Øivind; Gjershaug, Jan Ove; Gulliksen, Bjørn; Hamnes, Inger Sofie; Hatteland, Bjørn Arild; Hegre, Hanne; Hesthagen, Trygve H.; Jelmert, Anders; Jensen, Thomas Correll; Johnsen, Stein Ivar; Karlsbakk, Egil; Magnusson, Christer; Nedreaas, Kjell Harald; Nordén, Björn; Oug, Eivind; Pedersen, Oddvar; Pedersen, Per Anker; Sjøtun, Kjersti; Skei, Jon Kristian; Solstad, Heidi; Sundheim, Leif; Swenson, Jon; Syvertsen, Per Ole; Talgø, Venche; Vandvik, Vigdis; Westergaard, Kristine Bakke; Wienerroither, Rupert; Ytrehus, Bjørnar; Hilmo, Olga; Henriksen, Snorre; Gederaas, Lisbeth (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-03)
      We present the results of an inventory and status assessment of alien species in Norway. The inventory covered all known multicellular neobiota, 2496 in total, 1039 of which were classified as naturalised. The latter constitute c. 3% of all species known to be stably reproducing in Norway. These figures are higher than expected from Norway’s latitude, which may be due a combination of ...
    • Greenland Shark (Somniosus microcephalus) stomach contents and stable isotope values reveal an ontogenetic dietary shift 

      Nielsen, Julius; Christiansen, Jørgen Schou; Grønkjær, Peter; Bushnell, Peter G.; Steffensen, John Fleng; Kiilerich, Helene O.; Præbel, Kim; Hedeholm, Rasmus (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-04)
      Current knowledge on the feeding ecology of the Greenland shark (<i>Somniosus microcephalus</i>), a potential top predator in arctic marine ecosystems, is based on small sample sizes as well as narrow size ranges of sharks. Therefore, potential size-related feeding patterns remain poorly documented. Using stomach content data (<i>N</i> = 88) and stable isotope values of white muscle tissue (<i>N</i> ...
    • Dead or Alive; or Does It Really Matter? Level of Congruency Between Trophic Modes in Total and Active Fungal Communities in High Arctic Soil 

      Wutkowska, Magdalena; Vader, Anna; Mundra, Sunil; Cooper, Elisabeth J.; Eidesen, Pernille Bronken (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-08)
      Describing dynamics of belowground organisms, such as fungi, can be challenging. Results of studies based on environmental DNA (eDNA) may be biased as the template does not discriminate between metabolically active cells and dead biomass. We analyzed ribosomal DNA (rDNA) and ribosomal RNA (rRNA) coextracted from 48 soil samples collected from a manipulated snow depth experiment in two distinct ...
    • Efficient sampling for ecosystem service supply assessment at a landscape scale 

      Murguzur, Francisco Javier Ancin; Munoz, Lorena; Monz, Christopher; Fauchald, Per; Hausner, Vera Helene (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-19)
      Decision makers and stakeholders need high-quality data to manage ecosystem services (ES) efficiently. Landscape-level data on ES that are of sufficient quality to identify spatial tradeoffs, co-occurrence and hotspots of ES are costly to collect, and it is therefore important to increase the efficiency of sampling of primary data. We demonstrate how ES could be assessed more efficiently through ...
    • Rodent population cycle as a determinant of gastrointestinal nematode abundance in a low-arctic population of the red fox 

      Mørk, Torill; Ims, Rolf Anker; Killengreen, Siw Turid (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-22)
      We analyzed an 11-year time series (2005–2015) of parasite abundance for three intestinal nematode species in the red fox (<i>Vulpes vulpes</i>) as a function of the multi-annual rodent population cycle in low-arctic Norway, while correcting for other potential covariates that could influence prevalence and abundance. Rodents are paratenic and facultative intermediate hosts for the two Ascarididae ...
    • Contrasting associations between breeding coloration and parasitism of male Arctic charr relate to parasite species and life cycle stage 

      Johansen, Ida Beitnes; Henriksen, Eirik Haugstvedt; Shaw, Jenny Carolyn; Mayer, Ian; Amundsen, Per-Arne; Øverli, Øyvind (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-23)
      Conspicuous carotenoid ornamentation is considered a signal of individual “quality” and one of the most intensely studied traits found to co-vary with parasitism. Since it has been suggested that only “high quality” individuals have enough resources to express excessive sexual ornaments and resist parasites, current theory struggles to explain cases where the brightest individuals carry the most ...
    • Arctic charr brain transcriptome strongly affected by summer seasonal growth but only subtly by feed deprivation 

      Striberny, Anja; Jørgensen, Even Hjalmar; Klopp, Christophe; Magnanou, Elodie (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-27)
      <i>Background</i>: The Arctic charr (<i>Salvelinus alpinus</i>) has a highly seasonal feeding cycle that comprises long periods of voluntary fasting and a short but intense feeding period during summer. Therefore, the charr represents an interesting species for studying appetite-regulating mechanisms in fish. <p> <p><i>Results</i>: In this study, we compared the brain transcriptomes of fed and ...
    • Trophic interactions and abiotic factors drive functional and phylogenetic structure of vertebrate herbivore communities across the Arctic tundra biome 

      Speed, James David Mervyn; Skjelbred, Ina Åsnes; Barrio, Isabel C.; Martin, Michael David; Berteaux, Dominique; Bueno, Guillermo; Christie, Katie; Forbes, Bruce C.; Forbey, Jennifer; Fortin, Daniel; Grytnes, John-Arvid; Hoset, Katrine Skamfer; Lecomte, Nicolas; Marteinsdottir, Bryndis; Mosbacher, Jesper Bruun; Pedersen, Åshild Ø.; Ravolainen, Virve; Rees, Eileen C.; Skarin, Anna; Sokolova, Natalya; Thornhill, Andrew H; Tombre, Ingunn; Soininen, Eeva M (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-29)
      Communities are assembled from species that evolve or colonise a given geographic region, and persist in the face of abiotic conditions and interactions with other species. The evolutionary and colonisation histories of communities are characterised by phylogenetic diversity, while functional diversity is indicative of abiotic and biotic conditions. The relationship between functional and phylogenetic ...
    • Stakeholders’ perceptions of protected area management following a nationwide community-based conservation reform 

      Engen, Sigrid; Fauchald, Per; Hausner, Vera Helene (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-24)
      People’s perceptions can point to reasons for conservation support or lack thereof. In this study, we surveyed the perceptions of conservation among local stakeholders who participated in protected area (PA) management following a reform towards community-based conservation in Norway. We analyzed the link between perceptions of threats to conservation values, prioritized management actions and ...
    • Secondary Folds Contribute Significantly to the Total Surface Area in the Olfactory Organ of Chondrichthyes 

      Ferrando, Sara; Amaroli, Andrea; Gallus, Lorenzo; Aicardi, S; Di Blasi, D; Christiansen, Jørgen Schou; Vacchi, Marino; Ghigliotti, Laura (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-12)
      The olfactory organ of Chondrichthyes is characterized by a central support with several lamellae covered by a sensory olfactory epithelium. Although secondary folds are present on the lamellae in all the chondrichthyan species analyzed to date, their shape and size have not been described. We here analyze the olfactory organ of 13 elasmobranch and 1 holocephalan species, describe the shape of ...