Viser treff 149-168 av 1513

    • Caligus elongatus and other sea lice of the genus Caligus as parasites of farmed salmonids: A review 

      Hemmingsen, Willy; MacKenzie, Ken; Sagerup, Kjetil; Remen, Mette; Bloch-Hansen, Karin; Imsland, Albert (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-24)
      This review was prompted by reports of unusually large numbers of sea lice tentatively identified as <i>Caligus elongatus</i> infesting farmed salmon in northern Norway. Following a brief introduction to the sea lice problem in salmonid aquaculture, the review is divided into a further eight sections. The first is a review of existing information on the life cycle and behaviour of <i>Caligus</i> ...
    • Calving rates at tidewater glaciers vary strongly with ocean temperature 

      Luckman, Adrian; Benn, Doug; Cottier, Finlo; Bevan, Suzanne; Nilsen, Frank; Inall, Mark (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-09)
      Rates of ice mass loss at the calving margins of tidewater glaciers (frontal ablation rates) are a key uncertainty in sea level rise projections. Measurements are difficult because mass lost is replaced by ice flow at variable rates, and frontal ablation incorporates sub-aerial calving, and submarine melt and calving. Here we derive frontal ablation rates for three dynamically contrasting glaciers ...
    • Can a key boreal Calanus copepod species now complete its life-cycle in the Arctic? Evidence and implications for Arctic food-webs 

      Tarling, Geraint A.; Freer, Jennifer J.; Banas, Neil S.; Belcher, Anna; Blackwell, Mayleen; Castellani, Claudia; Cook, Kathryn B.; Cottier, Finlo Robert; Daase, Malin; Johnson, Magnus L.; Last, Kim S.; Lindeque, Penelope K.; Mayor, Daniel J.; Mitchell, Elaine; Parry, Helen E.; Speirs, Douglas C.; Stowasser, Gabriele; Wootton, Marianne (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-29)
      The changing Arctic environment is affecting zooplankton that support its abundant wildlife. We examined how these changes are influencing a key zooplankton species, Calanus finmarchicus, principally found in the North Atlantic but expatriated to the Arctic. Close to the ice-edge in the Fram Strait, we identified areas that, since the 1980s, are increasingly favourable to C. finmarchicus. Field-sampling ...
    • Can bryophyte groups increase functional resolution in tundra ecosystems? 

      Lett, Signe; Jonsdottir, Ingibjorg Svala; Cooper, Elisabeth; Becker-Scarpitta, Antoine; Christiansen, Casper T.; During, Heinjo; Ekelund, Flemming; Henry, Gregory H. R.; Lang, Simone I.; Michelsen, Anders; Rousk, Kathrin; Alatalo, Juha M.; Betway, Katlyn R.; Busca, Sara; Callaghan, Terry; Carbognani, Michele; Cornelissen, Hans C.; Dorrepaal, Ellen; Egelkraut, Dagmar; Elumeeva, Tatiana G.; Hollister, Robert D.; Jägerbrand, Annika K.; Keuper, Frida; Klanderud, Kari; Lévesque, Esther; Liu, Xin; May, Jeremy; Michel, Pascale; Mörsdorf, Martin; Petraglia, Alessandro; Rixen, Christian; Robroek, Bjorn J.M.; Rzepczynska, Agnieszka M.; Soudzilovskaia, Nadeja A.; Tolvanen, Anne; Vandvik, Vigdis; Volkov, Igor; Volkova, Irina; van Zuijlen, Kristel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-30)
      The relative contribution of bryophytes to plant diversity, primary productivity, and ecosystem functioning increases towards colder climates. Bryophytes respond to environmental changes at the species level, but because bryophyte species are relatively difficult to identify, they are often lumped into one functional group. Consequently, bryophyte function remains poorly resolved. Here, we explore ...
    • Can bryophyte groups increase functional resolution in tundra ecosystems? 

      Lett, Signe; Jónsdóttir, Ingibjörg Svala; Becker-Scarpitta, Antoine; Christiansen, Casper T.; During, Heinjo; Ekelund, Flemming; Henry, Greg H.R.; Lang, Simone; Michelsen, Anders; Rousk, Kathrin; Alatalo, Juha; Betway, Katlyn Rose; Busca, Sara; Callaghan, Terry; Carbognani, Michele; Cooper, Elisabeth J.; Cornelissen, J. Hans C.; Dorrepaal, Ellen; Egelkraut, Dagmar Dorothea; Elumeeva, Tatiana G.; Haugum, Siri Vatsø; Hollister, Robert D.; Jägerbrand, Annika K.; Keuper, Frida; Klanderud, Kari; Lévesque, Esther; Liu, Xin; May, Jeremy L.; Michel, Pascale; Mörsdorf, Martin; Petraglia, Alessandro; Rixen, Christian; Robroek, Bjorn J.M.; Rzepczynska, Agnieszka M.; Soudzilovskaia, Nadejda A.; Tolvanen, Anne; Vandvik, Vigdis; Volkov, Igor; Volkova, Irina; van Zuijlen, Kristel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-30)
      The relative contribution of bryophytes to plant diversity, primary productivity, and ecosystem functioning increases towards colder climates. Bryophytes respond to environmental changes at the species level, but because bryophyte species are relatively difficult to identify, they are often lumped into one functional group. Consequently, bryophyte function remains poorly resolved. Here, we explore ...
    • Can morphology reliably distinguish between the copepods Calanus finmarchicus and C. glacialis, or is DNA the only way? 

      Choquet, Marvin; Kosobokova, Ksenia; Kwaśniewski, Sławomir; Hatlebakk, Maja Karoline Viddal; Dhanasiri, Anusha Krishanthi Shyama; Melle, Webjørn Raunsgård; Daase, Malin; Svensen, Camilla; Søreide, Janne; Hoarau, Galice Guillaume (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-10)
      Copepods of the genus <i>Calanus</i> play a key role in marine food webs as consumers of primary producers and as prey for many commercially important marine species. Within the genus, <i>Calanus glacialis</i> and <i>Calanus finmarchicus</i> are considered indicator species for Arctic and Atlantic waters, respectively, and changes in their distributions are frequently used as a tool to track climate ...
    • Can multitrophic interactions and ocean warming influence large-scale kelp recovery? 

      Christie, Hartvig C; Gundersen, Hege; Rinde, Eli; Filbee-Dexter, Karen; Norderhaug, Kjell Magnus; Pedersen, Torstein; Bekkby, Trine; Gitmark, Janne Kim; Fagerli, Camilla With (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-14)
      Ongoing changes along the northeastern Atlantic coastline provide an opportunity to explore the influence of climate change and multitrophic interactions on the recovery of kelp. Here, vast areas of sea urchin‐dominated barren grounds have shifted back to kelp forests, in parallel with changes in sea temperature and predator abundances. We have compiled data from studies covering more than 1,500‐km ...
    • Can novel pest outbreaks drive ecosystem transitions in northern-boreal birch forest? 

      Vindstad, Ole Petter Laksforsmo; Jepsen, Jane Uhd; Ek, Malin; Pepi, Adam A.; Ims, Rolf Anker (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-04)
      <p>1.The boreal biome exhibits distinct alternative ecosystem states with high and low levels of tree cover. Insect outbreaks facilitated by climate warming could potentially drive transitions from high to low tree cover states. We investigated whether two key premises for such outbreak‐induced transitions – critical thresholds (tipping points) and positive feedbacks that could maintain alternative ...
    • Can plastic related chemicals be indicators of plastic ingestion in an Arctic seabird? 

      Collard, France; Tulatz, Felix; Harju, Mikael; Herzke, Dorte; Bourgeon, Sophie; Gabrielsen, Geir Wing (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-22)
      For decades, the northern fulmar (Fulmarus glacialis) has been found to ingest and accumulate high loads of plastic due to its feeding ecology and digestive tract morphology. Plastic ingestion can lead to both physical and toxicological effects as ingested plastics can be a pathway for hazardous chemicals into seabirds' tissues. Many of these contaminants are ubiquitous in the environment and the ...
    • Can waste re-cycling increase the sustainability of animal feeds? 

      Jobling, Malcolm (Journal article; Tidsskriftartikkel, 2019)
      An annual procution of over one billion tonnes, and an economic turnover in excess of $US400 billion; this is the animal feed industry. The vast majority of animal feed is given to terrestrial farm animals; those reared for meat, and those used to produce eggs and dairy products. Fish feeds make up about 5% of the total volume of animal feeds and have a 10% share of marked sales. <p> <p>It is ...
    • Cannibalism and protective behavior of eggs in Arctic charr (Salvelinus alpinus) 

      Frye, Marilena; Egeland, Torvald Blikra; Nordeide, Jarle Tryti; Folstad, Ivar (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-28)
      From video recordings of spawning events, we quantified protective and cannibalistic behavior of Arctic charr occurring immediately after spawning. The number of fish cannibalizing on stray eggs was examined regarding (a) whether more than one male shed milt during the spawning event, that is, whether sperm competition occurred, (b) whether the sperm competition included few or many males, that is, ...
    • Car tire crumb rubber: Does leaching produce a toxic chemical cocktail in coastal marine systems? 

      Halsband, Claudia; Sørensen, Lisbet; Booth, Andy; Herzke, Dorte (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-23)
      Crumb rubber granulate (CRG) produced from end of life tires (ELTs) is commonly applied to synthetic turf pitches (STPs), playgrounds, safety surfaces and walkways. In addition to fillers, stabilizers, cross-linking agents and secondary components (e.g., pigments, oils, resins), ELTs contain a range of other organic compound and heavy metal additives. While previous environmental impact studies on ...
    • Carbon export in the seasonal sea ice zone north of Svalbard from winter to late summer 

      Dybwad, Christine; Assmy, Philipp; Olsen, Lasse Mork; Peeken, Ilka; Nikolopoulos, Anna; Krumpen, Thomas; Randelhoff, Achim; Tatarek, Agnieszka; Wiktor, Józef M.; Reigstad, Marit (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-21)
      Phytoplankton blooms in the Arctic Ocean's seasonal sea ice zone are expected to start earlier and occur further north with retreating and thinning sea ice cover. The current study is the first compilation of phytoplankton bloom development and fate in the seasonally variable sea ice zone north of Svalbard from winter to late summer, using short-term sediment trap deployments. Clear seasonal patterns ...
    • Carbon stocks and fluxes in the high latitudes: Using site-level data to evaluate Earth system models 

      Chadburn, Sarah E.; Krinner, Gerhard; Porada, Philipp; Bartsch, Annett; Beer, Christian; Belelli Marchesini, Luca; Boike, Julia; Ekici, Altug; Elberling, Bo; Friborg, Thomas; Hugelius, Gustaf; Johansson, Margareta; Kuhry, Peter; Kutzbach, Lars; Langer, Moritz; Lund, Magnus; Parmentier, Frans-Jan Willem; Peng, Shushi; van Huissteden, Ko; Wang, Tao; Westermann, Sebastian; Zhu, Dan; Burke, Eleanor J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-17)
      It is important that climate models can accurately simulate the terrestrial carbon cycle in the Arctic due to the large and potentially labile carbon stocks found in permafrost-affected environments, which can lead to a positive climate feedback, along with the possibility of future carbon sinks from northward expansion of vegetation under climate warming. Here we evaluate the simulation of tundra ...
    • Carotenoid metabolism during bilberry (Vaccinium myrtillus L.) fruit development under different light conditions is regulated by biosynthesis and degradation 

      Karppinen, Katja; Zoratti, Laura; Sarala, Marian; Carvalho, Elisabete; Hirsimäki, Jenni; Mentula, Helmi; Martens, Stefan; Häggman, Hely; Jaakola, Laura (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-04-21)
      <b>Background:</b> Carotenoids are important pigments and precursors for central signaling molecules associated in fruit development and ripening. Carotenoid metabolism has been studied especially in the climacteric tomato fruit but the content of carotenoids and the regulation of their metabolism have been shown to be highly variable between fruit species. Non-climacteric berries of the genus ...
    • CASCADE-The Circum-Arctic Sediment CArbon DatabasE 

      Martens, Jannik; Romankevich, Evgeny; Semiletov, Igor; Wild, Birgit; Van Dongen, Bart; Vonk, Jorien; Tesi, Tommaso; Shakhova, Natalia; Dudarev, Oleg V.; Kosmach, Denis; Vetrov, Alexander; Lobkovsky, Leopold; Belyaev, Nikolay; Macdonald, Robie W.; Pieńkowski, Anna J.; Eglinton, Timothy I.; Haghipour, Negar; Dahle, Salve; Carroll, Michael L.; Åström, Emmelie; Grebmeier, Jacqueline M.; Cooper, Lee W.; Possnert, Göran; Gustafsson, Örjan (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-08)
      Biogeochemical cycling in the semi-enclosed Arctic Ocean is strongly influenced by land–ocean transport of carbon and other elements and is vulnerable to environmental and climate changes. Sediments of the Arctic Ocean are an important part of biogeochemical cycling in the Arctic and provide the opportunity to study present and historical input and the fate of organic matter (e.g., through permafrost ...
    • Cascading effects of moth outbreaks on subarctic soil food webs 

      Calderón-Sanou, Irene; Münkemüller, Tamara; Zinger, Lucie; Schimann, Heidy; Yoccoz, Nigel; Gielly, Ludovic; Foulquier, Arnaud; Hedde, Mickael; Ohlmann, Marc; Roy, Mélanie; Si-Moussi, Sara; Thuiller, Wilfred (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-23)
      The increasing severity and frequency of natural disturbances requires a better understanding of their effects on all compartments of biodiversity. In Northern Fennoscandia, recent large-scale moth outbreaks have led to an abrupt change in plant communities from birch forests dominated by dwarf shrubs to grass-dominated systems. However, the indirect effects on the belowground compartment remained ...
    • Case report: Subclinical verminous pneumonia and high ambient temperatures had severe impact on the anesthesia of semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) with medetomidine-ketamine 

      Tryland, Morten; Josefsen, Terje D.; Sanchez Romano, Javier; Marcin, Nina; Mørk, Torill; Arnemo, Jon Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-24)
      Semidomesticated Eurasian tundra reindeer (<i>Rangifer tarandus tarandus, n</i> = 21) were scheduled twice for chemical immobilization with medetomidine–ketamine as part of a scientific experiment in June 2014. During the first round of immobilizations, seven animals developed severe respiratory depression (RD). Three individuals died, and 4 recovered. The ambient temperature during the 2 days of ...
    • causalizeR: a text mining algorithm to identify causal relationships in scientific literature 

      Ancin Murguzur, Francisco Javier; Hausner, Vera Helene (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-20)
      Complex interactions among multiple abiotic and biotic drivers result in rapid changes in ecosystems worldwide. Predicting how specific interactions can cause ripple effects potentially resulting in abrupt shifts in ecosystems is of high relevance to policymakers, but difficult to quantify using data from singular cases. We present causalizeR (https://github.com/fjmurguzur/causalizeR), a text-processing ...
    • Causes and consequences of ontogenetic dietary shifts: a global synthesis using fish models 

      Sanchez-Hernandez, Javier; Nunn, Andy D; Adams, Colin Ean; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-09-24)
      Ontogenetic dietary shifts (ODSs), the changes in diet utilisation occurring over the life span of an individual consumer, are widespread in the animal kingdom. Understanding ODSs provides fundamental insights into the biological and ecological processes that function at the individual, population and community levels, and is critical for the development and testing of hypotheses around key concepts ...