Viser treff 801-820 av 1637

    • Nitrate supply and uptake in the Atlantic Arctic sea ice zone: seasonal cycle, mechanisms and drivers 

      Henley, Sian F.; Porter, Marie; Hobbs, Laura; Braun, Judith; Guillaume-Castel, Robin; Venables, Emily J.; Dumont, Estelle; Cottier, Finlo Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-31)
      Nutrient supply to the surface ocean is a key factor regulating primary production in the Arctic Ocean under current conditions and with ongoing warming and sea ice losses. Here we present seasonal nitrate concentration and hydrographic data from two oceanographic moorings on the northern Barents shelf between autumn 2017 and summer 2018. The eastern mooring was sea ice-covered to varying degrees ...
    • Interfering with neighbouring communities: Allelopathy astray in the tundra delays seedling development 

      Pilsbacher, Anna Katharina; Lindgård, Bente; Reiersen, Rigmor; González, Victoria T.; Bråthen, Kari Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-06)
      <ol> <li>Altered species composition caused by environmental and climatic change can affect the transfer of plant residues among communities. Whereas transferred residues are typically considered a resource in recipient systems, residues of allelopathic species may instead cause interference.</li> <li>Evergreen dwarf shrubs, specifically the allelopathic species Empetrum nigrum are increasing ...
    • Gonads or body? Differences in gonadal and somatic photoperiodic growth response in two vole species 

      van Rosmalen, Laura; van Dalum, Mattis Jayme; Hazlerigg, David; Hut, Roelof A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-21)
      To optimally time reproduction, seasonal mammals use a photoperiodic neuroendocrine system (PNES) that measures photoperiod and subsequently drives reproduction. To adapt to late spring arrival at northern latitudes, a lower photoperiodic sensitivity and therefore a higher critical photoperiod for reproductive onset is necessary in northern species to arrest reproductive development until spring ...
    • Anaerobic oxidation of methane and associated microbiome in anoxic water of Northwestern Siberian lakes 

      Cabrol, Lea; Thalasso, Frederic; Gandois, Laure; Sepulveda-Jauregui, Armando; Martinez-Cruz, Karla; Teisserenc, Roman; Tananaev, Nikita; Tveit, Alexander Tøsdal; Svenning, Mette M.; Barret, Maialen (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-25)
      Arctic lakes emit methane (CH<sub>4</sub>) to the atmosphere. The magnitude of this flux could increase with permafrost thaw but might also be mitigated by microbial CH4 oxidation. Methane oxidation in oxic water has been extensively studied, while the contribution of anaerobic oxidation of methane (AOM) to CH<sub>4</sub> mitigation is not fully understood. We have investigated four Northern Siberian ...
    • Growth and behaviour of blue mussels, a re-emerging polar resident, follow a strong annual rhythm shaped by the extreme high Arctic light regime: Mussels' growth and behavior in Arctic 

      Tran, Damien; Andrade Rodriguez, Hector Antonio; Durier, Guillaume; Ciret, Pierre; Leopold, Peter; Sow, Mohamedou; Ballantine, Carl; Camus, Lionel; Berge, Jørgen; Perrigault, Mickael (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-14)
      Polar regions are currently warming at a rate above the global average. One issue of concern is the consequences on biodiversity in relation to the Northward latitudinal shift in distribution of temperate species. In the present study, lasting almost two years, we examined two phenological traits, i.e. the shell growth and behavioural rhythm of a recently re-established species in the high Arctic, ...
    • Changes in Sea-Ice Protist Diversity With Declining Sea Ice in the Arctic Ocean From the 1980s to 2010s 

      Hop, Haakon; Vihtakari, Mikko; Bluhm, Bodil; Assmy, Philipp; Poulin, Michel; Gradinger, Rolf; Peeken, Ilka; von Quillfeldt, Cecilie; Olsen, Lasse Mork; Zhitina, Ludmila; Melnikov, Igor A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-06)
      The large declines in Arctic sea-ice age and extent over the last decades could have altered the diversity of sea-ice associated unicellular eukaryotes (referred to as sea-ice protists). A time series from the Russian ice-drift stations from the 1980s to the 2010s revealed changes in community composition and diversity of sea-ice protists from the Central Arctic Ocean. However, these observations ...
    • The impact of thermal seasonality on terrestrial endotherm food web dynamics: a revision of the Exploitation Ecosystem Hypothesis 

      Oksanen, Tarja Maarit; Oksanen, Lauri; Vuorinen, Katariina; Wolf, Christopher; Mäkynen, Aurelia; Olofsson, Johan; Ripple, William J.; Virtanen, Risto; Utsi, Tove Aagnes (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-06)
      Many terrestrial endotherm food webs constitute three trophic level cascades. Others have two trophic level dynamics (food limited herbivores; plants adapted to tackle intense herbivory) or one trophic level dynamic (herbivorous endotherms absent, thus plants compete for the few places where they can survive and grow). According to the Exploitation Ecosystems Hypothesis (EEH), these contrasting ...
    • A risk assessment of the effects of mercury on Baltic Sea, Greater North Sea and North Atlantic wildlife, fish and bivalves 

      Dietz, Rune; Fort, Jérôme; Sonne, Christian; Albert, Céline; Bustnes, Jan Ove; Christensen, Thomas Kjær; Ciesielski, Tomasz Maciej; Danielsen, Jóhannis; Dastnai, Sam; Eens, Marcel; Erikstad, Kjell E; Galatius, Anders; Garbus, Svend-Erik; Gilg, Oliver; Hanssen, Sveinn Are; Helander, Björn; Helberg, Morten; Jaspers, Veerle; Jenssen, Bjørn Munro; Jónsson, Jón Einar; Kauhala, Kaarina; Kolbeinsson, Yann; Kyhn, Line A.; Labansen, Aili Lage; Larsen, Martin M.; Lindstrøm, Ulf; Reiertsen, Tone Kristin; Rigét, Frank F.; Roos, Anna; Strand, Jakob; Strøm, Hallvard; Søndergaard, Jens; Sun, Jiachen; Teilmann, Jonas; Therkildsen, Ole Roland; Thórarinsson, Thorkell Lindberg; Tjørnløv, Rune Skjold; Wilson, Simon; Eulaers, Igor (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-24)
      A wide range of species, including marine mammals, seabirds, birds of prey, fish and bivalves, were investigated for potential population health risks resulting from contemporary (post 2000) mercury (Hg) exposure, using novel risk thresholds based on literature and de novo contamination data. The main geographic focus is on the Baltic Sea, while data from the same species in adjacent waters, such ...
    • Tap av tamrein – et kunnskapsgrunnlag 

      Hansen, Inger; Eilertsen, Svein Morten; Sørensen, Ole Jakob; Mørk, Torill; Bråthen, Kari Anne; Johansen, Bernt; Moa, Pål Fossland; Risvoll, Camilla; Sandström, Camilla; Winje, Erlend (Research report; Forskningsrapport, 2019-12-30)
      Tap av dyr er en utfordring og et sentralt tema i norsk tamreindrift. Dette kunnskapsgrunnlaget beskriver status for hva vi vet om tapsomfang, tapsårsaker og tapsammenhenger innen områdene tap av rein til rovvilt, sykdom, klimarelatert tap, påkjørsler og grunnet kumulative effekter. Videre setter den fokus på forebyggende tiltak og hvilke felt man trenger ytterligere kunnskapsbygging på. Gjennomgående ...
    • Influence of glacial water and carbonate minerals on wintertime sea-ice biogeochemistry and the CO2 system in an Arctic fjord in Svalbard 

      Fransson, Agneta; Chierici, Melissa; Nomura, Daiki; Granskog, Mats; Kristiansen, Svein; Martma, Tõnu; Nehrke, Gernot (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-13)
      The effect of freshwater sources on wintertime sea-ice CO2 processes was studied from the glacier front to the outer Tempelfjorden, Svalbard, in sea ice, glacier ice, brine and snow. March–April 2012 was mild, and the fjord was mainly covered with drift ice, in contrast to the observed thicker fast ice in the colder April 2013. This resulted in different physical and chemical properties of the sea ...
    • Proceedings of the Norwegian Environmental Toxicology Symposium, 2018 

      Waugh, Courtney; Reinardy, Helena; Jenssen, Bjørn Munro (Conference object; Konferansebidrag, 2018)
    • Skogens helsetilstand i Norge. Resultater fra skogskadeovervåkingen i 2018 

      Timmermann, Volkmar; Andreassen, Kjell; Brurberg, May Bente; Børja, Isabella; Clarke, Nicholas; Flø, Daniel; Jepsen, Jane Uhd; Kvamme, Torstein; Nordbakken, Jørn-Frode; Nygaard, Per Holm; Pettersson, Martin; Solberg, Sverre; Solheim, Halvor; Talgø, Venche; Vinstad, O.P.L; Wollebæk, Gro; Økland, Bjørn; Aas, Wenche (Research report; Forskningsrapport, 2019)
      Skogens helsetilstand påvirkes i stor grad av klima og værforhold, enten direkte ved tørke, frost og vind, eller indirekte ved at klimaet påvirker omfanget av soppsykdommer og insektangrep. Klimaendringene og den forventede økningen i klimarelaterte skogskader gir store utfordringer for forvaltningen av framtidas skogressurser. Det samme gjør invaderende skadegjørere, både allerede etablerte arter ...
    • Skogens helsetilstand i Norge. Resultater fra skogskadeovervåkingen i 2017 

      Timmermann, Volkmar; Andreassen, Kjell; Brurberg, May Bente; Clarke, Nicholas; Herrero, Maria-Luz; Jepsen, Jane Uhd; Vindstad, Ole Petter Laksforsmo (Research report; Forskningsrapport, 2018)
      Skogens helsetilstand påvirkes i stor grad av klima og værforhold, enten direkte ved tørke, frost og vind, eller indirekte ved at klimaet påvirker omfanget av soppsykdommer og insektangrep. Klimaendringene og den forventede økningen i klimarelaterte skogskader gir store utfordringer for forvaltningen av framtidas skogressurser. Det samme gjør invaderende skadegjørere, både allerede etablerte arter ...
    • Epibenthic megafauna communities in Northeast Greenland vary across coastal, continental shelf and slope habitats 

      Fredriksen, Rosalyn; Christiansen, Jørgen Schou; Bonsdorff, Erik; Larsen, Lars-Henrik; Nordström, Marie C.; Zhulay, Irina; Bluhm, Bodil (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-29)
      The marine area of Northeast Greenland belongs to the largest national park in the world. Biodiversity assessments and tailored conservation measures often target specific physiographic or oceanographic features of an area for which detailed knowledge on their biological communities is incomplete. This study, therefore, characterizes epibenthic megafauna communities in a priori defined seabed habitats ...
    • Arctic (Svalbard islands) active and exported diatom stocks and cell health status 

      Agustí, Susana; Krause, Jeffrey W.; Marquez, Israel A.; Wassmann, Paul; Kristiansen, Svein; Duarte, Carlos M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-03)
      Diatoms tend to dominate the Arctic spring phytoplankton bloom, a key event in the ecosystem including a rapid decline in surface-water <i>p</i>CO<sub>2</sub>. While a mass sedimentation event of diatoms at the bloom terminus is commonly observed, there are few reports on the status of diatoms' health during Arctic blooms and its possible role on sedimentary fluxes. Thus, we examine the idea that ...
    • The need for transformative changes in the use of Indigenous knowledge along with science for environmental decision-making in the Arctic 

      Wheeler, Helen; Danielsen, Finn; Fidel, Maryann; Hausner, Vera Helene; Horstkotte, Tim; Johnson, Noor; Lee, Olivia; Mukherjee, Nibedita; Amos, Amy; Ashtorn, Heather; Ballari, Øystein; Behe, Carolina; Breton‐Honeyman, Kaitlin; Retter, Gunn-Britt; Buschman, Victoria; Jakobsen, Pâviârak; Johnson, Frank; Lyberth, Bjarne; Parrott, Jennifer A.; Pogodaev, Mikhail; Sulyandziga, Rodion; Vronski, Nikita (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-03)
      <ol> <li>Recent attention to the role of Indigenous knowledge (IK) in environmental monitoring, research and decision‐making is likely to attract new people to this field of work.</li> <li>Advancing the bringing together of IK and science in a way that is desirable to IK holders can lead to successful and inclusive research and decision‐making.</li> <li>We used the Delphi technique with 18 ...
    • Using crowdsourced spatial data from Flickr vs. PPGIS for understanding nature's contribution to people in Southern Norway 

      Munoz, Lorena; Hausner, Vera Helene; Runge, Claire Alice; Brown, Greg; Daigle, Remi (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-20)
      <ol> <li>Crowdsourced data can provide spatially explicit data on the contribution of nature to people. Spatial information is essential for effectively managing the diverse relationships that people have with nature, but the potential and limits of using crowdsourcing data to generate maps for conservation purposes need further research. </li><p> <p><li>Passive crowdsourcing tools include social ...
    • Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches 

      Renedo, Marina; Amouroux, David; Albert, Céline; Bérail, Sylvain; Bråthen, Vegard Sandøy; Gavrilo, Maria; Grémillet, David; Helgason, Hálfdán H.; Jakubas, Dariusz; Mosbech, Anders; Strøm, Hallvard; Tessier, Emmanuel; Wojczulanis-Jakubas, Katarzyna; Bustamante, Paco; Fort, Jérôme (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-16)
      Despite the limited direct anthropogenic mercury (Hg) inputs in the circumpolar Arctic, elevated concentrations of methylmercury (MeHg) are accumulated in Arctic marine biota. However, the MeHg production and bioaccumulation pathways in these ecosystems have not been completely unraveled. We measured Hg concentrations and stable isotope ratios of Hg, carbon, and nitrogen in the feathers and blood ...
    • Transcriptome sequencing and histology reveal dosage compensation in the liver of triploid pre-smolt Atlantic salmon 

      Odei, Derrick Kwame; Hagen, Ørjan; Peruzzi, Stefano; Falk-Petersen, Inger-Britt; Fernandes, Jorge Manuel de Oliveira (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-08)
      Triploid Atlantic salmon (<i>Salmo salar</i> L.) is seen as one of the best solutions to solve key issues in the salmon farming industry, such as the impact of escapees on wild stocks and pre-harvest sexual maturation. However, the effects of triploidy on salmon smoltification are poorly understood at the molecular level, even though smoltification is a very sensitive period that has a major influence ...
    • Evidence for oscillating circadian clock genes in the copepod Calanus finmarchicus during the summer solstice in the high Arctic 

      Hüppe, Lukas; Payton, Laura; Last, Kim; Wilcockson, David; Ershova, Elizaveta; Meyer, Bettina (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-15)
      The circadian clock provides a mechanism for anticipating environmental cycles and is synchronized by temporal cues such as daily light/dark cycle or photoperiod. However, the Arctic environment is characterized by several months of Midnight Sun when the sun is continuously above the horizon and where sea ice further attenuates photoperiod. To test if the oscillations of circadian clock genes remain ...