Now showing items 641-660 of 1629

    • Food web approach for managing Arctic wildlife populations in an era of rapid environmental change 

      Mellard, Jarad; Henden, John-André; Pedersen, Åshild Ønvik; Marolla, Filippo; Hamel, Sandra; Yoccoz, Nigel; Ims, Rolf Anker (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-28)
      Scientists and wildlife managers implementing adaptive monitoring and management schemes, are tasked with providing predictions of population responses to harvest and environmental changes. Such predictions are useful not only to forecast direct effects of climate, productivity, land use, or habitat degradation, but also changes in the food web, such as expanding/increasing species that are predators, ...
    • Direct and indirect effects of environmental drivers on reindeer reproduction 

      Henden, John-André; Tveraa, T.; Stien, Audun; Mellard, Jarad; Marolla, Filippo; Ims, Rolf Anker; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-27)
      The impact of climate change on the dynamics of populations has been well documented and is widespread. However, weather variability influences populations both directly and indirectly, and is mediated by species interactions. This complexity may impede proper climate impact assessments. Hence, predicting the consequences of climate change may require including processes that occur both with time ...
    • Will borealization of Arctic tundra herbivore communities be driven by climate warming or vegetation change? 

      Speed, James David Mervyn; Chimal-Ballesteros, J. Adrian; Martin, Michael D.; Barrio, Isabel C.; Vuorinen, Katariina Elsa Maria; Soininen, Eeva M (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-30)
      Poleward shifts in species distributions are expected and frequently observed with a warming climate. In Arctic ecosystems, the strong warming trends are associated with increasing greenness and shrubification. Vertebrate herbivores have the potential to limit greening and shrub advance and expansion on the tundra, posing the question of whether changes in herbivore communities could partly mediate ...
    • MYBA and MYBPA transcription factors co-regulate anthocyanin biosynthesis in blue-coloured berries 

      Karppinen, Katja; Lafferty, Declan J.; Albert, Nick W.; Mikkola, Nelli; McGhie, Tony K.; Allan, Andrew C.; Afzal, Bilal M.; Häggman, Hely; Espley, Richard V.; Jaakola, Laura (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-05)
      <p>We used blue berries of bilberry (Vaccinium myrtillus) to comprehensively characterise flavonoid-regulating R2R3 MYBs, which revealed a new type of co-regulation in anthocyanin biosynthesis between members of MYBA-, MYBPA1- and MYBPA2-subgroups. <p>VmMYBA1, VmMYBPA1.1 and VmMYBPA2.2 expression was elevated at berry ripening and by abscisic acid treatment. Additionally, VmMYBA1 and VmMYBPA1.1 ...
    • Ice-Associated Amphipods in a Pan-Arctic Scenario of Declining Sea Ice 

      Hop, Haakon; Vihtakari, Mikko; Bluhm, Bodil; Daase, Malin; Gradinger, Rolf; Melnikov, Igor A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-13)
      Sea-ice macrofauna includes ice amphipods and benthic amphipods, as well as mysids. Amphipods are important components of the sympagic food web, which is fuelled by the production of ice algae. Data on the diversity of sea-ice biota have been collected as a part of scientific expeditions over decades, and here we present a pan-Arctic analysis of data on ice-associated amphipods and mysids assimilated ...
    • Modelling the biogeographic boundary shift of Calanus finmarchicus reveals drivers of Arctic Atlantification by subarctic zooplankton 

      Freer, Jennifer; Daase, Malin; Tarling, Geraint A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-15)
      Biological communities in the Arctic are changing through the climate-driven encroachment of subarctic species. This “Atlantification” extends to keystone Calanoid copepods, as the small-bodied Calanus finmarchicus increases in abundance in areas where it overlaps with larger Arctic congeners. The environmental factors that are facilitating this shift, whether related to optimal conditions in ...
    • Red and blue light treatments of ripening bilberry fruits reveal differences in signalling through abscisic acid-regulated anthocyanin biosynthesis 

      Samkumar, Amos; Jones, Dan; Karppinen, Katja; Dare, Andrew P.; Sipari, Nina; Espley, Richard V.; Martinussen, Inger; Jaakola, Laura (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-01)
      The biosynthesis of anthocyanins has been shown to be influenced by light quality. However, the molecular mechanisms underlying the light-mediated regulation of fruit anthocyanin biosynthesis are not well understood. In this study, we analysed the effects of supplemental red and blue light on the anthocyanin biosynthesis in non-climacteric bilberry (<i>Vaccinium myrtillus</i> L.). After 6 days of ...
    • Parasitoids indicate major climate-induced shifts in arctic communities 

      Kankaanpää, Tuomas; Vesterinen, Eero; Hardwick, Bess; Schmidt, Niels M.; Andersson, Tommi; Aspholm, Paul E.; Barrio, Isabel C.; Beckers, Niklas; Bêty, Joël; Birkemoe, Tone; DeSiervo, Melissa; Drotos, Katherine H.I.; Ehrich, Dorothee; Gilg, Olivier; Gilg, Vladimir; Hein, Nils; Høye, Toke T.; Jakobsen, Kristian M.; Jodouin, Camille; Jorna, Jesse; Kozlov, Mikhail V.; Kresse, Jean-Claude; Leandri-Breton, Don-Jean; Lecomte, Nicolas; Loonen, Maarten; Marr, Philipp; Monckton, Spencer K.; Olsen, Maia; Otis, Josée-Anne; Pyle, Michelle; Roos, Ruben Erik; Raundrup, Katrine; Rozhkova, Daria; Sabard, Brigitte; Sokolov, Aleksandr; Sokolova, Natalia; Solecki, Anna M.; Urbanowicz, Christine; Villeneuve, Catherine; Vyguzova, Evgenya; Zverev, Vitali; Roslin, Tomas (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-05)
      Climatic impacts are especially pronounced in the Arctic, which as a region is warming twice as fast as the rest of the globe. Here, we investigate how mean climatic conditions and rates of climatic change impact parasitoid insect communities in 16 localities across the Arctic. We focus on parasitoids in a widespread habitat, Dryas heathlands, and describe parasitoid community composition in terms ...
    • Finding the needle in the haystack: Comparison of methods for salmon louse enumeration in plankton samples 

      Bui, Samantha; Dalvin, Sussie; Vågseth, Tone; Oppedal, Frode; Fossøy, Frode; Brandsegg, Hege; Jacobsen, Ása; Nordi, Gunnvør á; Fordyce, Mark; Michelsen, Helena Kling; Finstad, Bengt; Skern-Mauritzen, Rasmus (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-07)
      The economic and social implications of salmon louse (Lepeophtheirus salmonis) epidemics in salmon aquaculture drive focus of the dispersal dynamics of the planktonic larval stages. The vast spatial scale and high connectivity of the marine environment creates difficult conditions to monitor the infective planktonic louse stage, whereby the number of samples required for a representative description ...
    • Overexploitation, Recovery, and Warming of the Barents Sea Ecosystem During 1950–2013 

      Pedersen, Torstein; Mikkelsen, Nina; Lindstrøm, Ulf; Renaud, Paul Eric; Nascimento, Marcela C.; Blanchet, Marie-Anne; Ellingsen, Ingrid H.; Jørgensen, Lis L.; Blanchet, Hugues (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-17)
      The Barents Sea (BS) is a high-latitude shelf ecosystem with important fisheries, high and historically variable harvesting pressure, and ongoing high variability in climatic conditions. To quantify carbon flow pathways and assess if changes in harvesting intensity and climate variability have affected the BS ecosystem, we modeled the ecosystem for the period 1950–2013 using a highly trophically ...
    • The paradox of forbs in grasslands and the legacy of the mammoth steppe 

      Bråthen, Kari Anne; Pugnaire, Francisco I; Bardgett, Richard D (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-07)
      The grassland biome supports an enormous diversity of life and includes ecosystems used extensively by humans. Although graminoids lend grasslands their characteristic appearance, forbs are largely responsible for their taxonomic, phylogenetic, and functional diversity. In terms of abundance, however, forbs often play a subordinate role relative to graminoids. Yet this may be a relatively recent ...
    • Cultural and linguistic diversities are underappreciated pillars of biodiversity 

      Frainer, Andre barbosa; Mustonen, Tero; Hugu, Sutej; Andreeva, Tamara; Arttijeff, Elle-Maarit; Arttijeff, Inka-Saara; Brizoela, Felipe; Coelho-De-Souza, Gabriela; Printes, Rafaela Biehl; Prokhorova, Evgenia; Sambou, Salatou; Scherer, Antoine; Shadrin, Vyacheslav; Pecl, Gretta (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-07)
    • Sea ice reduction drives genetic differentiation among Barents Sea polar bears 

      Maduna, Simo; Aars, Jon; Fløystad, Ida; Klutsch, Cornelya; Fiskebeck, Eve Marie Louise Zeyl; Wiig, Øystein; Ehrich, Dorothee; Andersen, Magnus; Bachmann, Lutz; Derocher, Andrew E.; Nyman, Tommi; Eiken, Hans Geir; Hagen, Snorre (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-08)
      Loss of Arctic sea ice owing to climate change is predicted to reduce both genetic diversity and gene flow in ice-dependent species, with potentially negative consequences for their long-term viability. Here, we tested for the population-genetic impacts of reduced sea ice cover on the polar bear (<i>Ursus maritimus</i>) sampled across two decades (1995–2016) from the Svalbard Archipelago, Norway, ...
    • Time-series of cloud-free sentinel-2 ndvi data used in mapping the onset of growth of central Spitsbergen, Svalbard 

      Karlsen, Stein Rune; Stendardi, Laura; Tømmervik, Hans; Nilsen, Lennart; Arntzen, Ingar; Cooper, Elisabeth J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-02)
      The Arctic is a region that is expected to experience a high increase in temperature. Changes in the timing of phenological phases, such as the onset of growth (as observed by remote sensing), is a sensitive bio-indicator of climate change. In this paper, the study area was the central part of Spitsbergen, Svalbard, located between 77.28°N and 78.44°N. The goals of this study were: (1) to prepare, ...
    • Effect of scavenging on predation in a food web 

      Mellard, Jarad; Hamel, Sandra; Henden, John-André; Ims, Rolf Anker; Stien, Audun; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-26)
      <ol> <li>The fasting endurance hypothesis (FEH) predicts strong selection for large body size in mammals living in environments where food supply is interrupted over prolonged periods of time. The Arctic is a highly seasonal and food-restricted environment, but contrary to predictions from the FEH, empirical evidence shows that Arctic mammals are often smaller than their temperate conspecifics. ...
    • Microbial responses to herbivory-induced vegetation changes in a high-Arctic peatland 

      Bender, Kathrin Marina; Svenning, Mette Marianne; Hu, Yuntao; Richter, Andreas; Schückel, Julia; Jørgensen, Bodil; Liebner, Susanne; Tveit, Alexander Tøsdal (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-30)
      Herbivory by barnacle geese (<i>Branta leucopsis</i>) alters the vegetation cover and reduces ecosystem productivity in high-Arctic peatlands, limiting the carbon sink strength of these ecosystems. Here we investigate how herbivory-induced vegetation changes affect the activities of peat soil microbiota using metagenomics, metatranscriptomics and targeted metabolomics in a comparison of fenced ...
    • Poleward shifts in marine fisheries under Arctic warming 

      Fauchald, Per; Arneberg, Per; Debernard, Jens Boldingh; Lind, Sigrid; Olsen, Erik; Hausner, Vera Helene (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-16)
      As global warming makes the Arctic Ocean more accessible, concerns have been raised about the environmental consequences of a possible expansion of commercial fisheries into pristine marine ecosystems. Using a recently released global dataset, we quantify for the first time how fishing activities are responding to diminishing sea ice and a warmer Arctic Ocean. We show that trawling dominates Arctic ...
    • Climate variability and density-dependent population dynamics: Lessons from a simple High Arctic ecosystem 

      Fauteux, Dominique; Stien, Audun; Yoccoz, Nigel; Fuglei, Eva; Ims, Rolf Anker (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-09)
      Ecologists are still puzzled by the diverse population dynamics of herbivorous small mammals that range from high-amplitude, multiannual cycles to stable dynamics. Theory predicts that this diversity results from combinations of climatic seasonality, weather stochasticity, and density-dependent food web interactions. The almost ubiquitous 3- to 5-y cycles in boreal and arctic climates may theoretically ...
    • Developing common protocols to measure tundra herbivory across spatial scales 

      Barrio, Isabel C.; Ehrich, Dorothee; Soininen, Eeva M; Ravolainen, Virve; Bueno, C. G.; Gilg, Olivier; Koltz, Amanda; Speed, James David Mervyn; Hik, David S.; Mörsdorf, M.; Alatalo, Juha M.; Angerbjørn, A.; Bêty, Joël; Bollache, L.; Boulanger-Lapointe, N.; Brown, G. S.; Eischeid, Isabell; Giroux, M. A.; Hajek, T.; Hansen, Brage Bremset; Hofhius, S. P.; Lamarre, J.-F.; Lang, J.; Latty, C.; Lecomte, N.; Macek, P.; McKinnon, L.; Myers-Smith, I. H.; Pedersen, Åshild Ønvik; Prevey, J. S.; Roth, J. D.; Saalfeld, S. T.; Schmidt, N. M.; Smith, P.; Sokolov, A.; Sokolova, N.; Stolz, C.; van Bemmelen, R.; Varpe, Øystein; Woodard, P. F.; Jonsdottir, I. S. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-12)
      Understanding and predicting large-scale ecological responses to global environmental change requires comparative studies across geographic scales with coordinated efforts and standardized methodologies. We designed, applied, and assessed standardized protocols to measure tundra herbivory at three spatial scales: plot, site (habitat), and study area (landscape). The plot- and site-level protocols ...
    • Moving forward in microplastic research: A Norwegian perspective 

      Lusher, Amy; Hurley, Rachel; Arp, Hans Peter H; Booth, Andy; Bråte, Inger Lise Nerland; Gabrielsen, Geir W.; Gomiero, Alessio; Gomes, Tania; Grøsvik, Bjørn Einar; Green, Norman; Haave, Marte; Hallanger, Ingeborg G.; Halsband, Claudia; Herzke, Dorte; Joner, Erik J; Kögel, Tanja; Rakkestad, Kirsten; Ranneklev, Sissel Brit; Wagner, Martin; Olsen, Marianne (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-03)
      Given the increasing attention on the occurrence of microplastics in the environment, and the potential envi-ronmental threats they pose, there is a need for researchers to move quickly from basic understanding to applied science that supports decision makers in finding feasible mitigation measures and solutions. At the same time, they must provide sufficient, accurate and clear information to the ...