• Age-dependent genetic structure of arctic foxes in Svalbard 

      Ehrich, Dorothee; Carmichael, Lindsey; Fuglei, Eva (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
    • Aggregate feeding by the copepods Calanus and Pseudocalanus controls carbon flux attenuation in the Arctic shelf sea during the productive period 

      van der Jagt, Helga; Wiedmann, Ingrid; Hildebrandt, Nicole; Niehoff, Barbara; Iversen, Morten H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-24)
      Up to 95% of the oceanic primary production is recycled within the upper few hundred meters of the water column. Marine snow and zooplankton fecal pellets in the upper water column are often recycled at rates exceeding those measured for microbial degradation, suggesting that zooplankton might be important for flux attenuation of particulate organic carbon in the upper ocean. However, direct evidence ...
    • Aggregative response in white-tailed eagles- an initial study of the terrestrial implications of invasive Pacific pink salmons (Oncorhynchus gorbuscha) in northern Norway. 

      Bonde, Bror Mathias (Master thesis; Mastergradsoppgave, 2023-05-15)
      Abstract The spawning population of invasive Pacific pink salmon (Oncorhynchus gorbuscha) has only continued to increase in the river systems on the Varanger peninsula in Norway, causing concerns across institutional boundaries and management communities. So far, the Norwegian research efforts on Pacific pink salmon have been centred on consequential effects in marine- and freshwater ecosystems, ...
    • Algal hot spots in a changing Arctic Ocean: Sea-ice ridges and the snow-ice interface 

      Fernández-Méndez, Mar; Olsen, Lasse Mork; Kauko, Hanna M.; Meyer, Amelie; Rösel, Anja; Merkouriadi, Ioanna; Mundy, Christopher John; Ehn, Jens K.; Johansson, Malin; Wagner, Penelope Mae; Ervik, Åse; Sorrell, BK; Duarte, Pedro; Wold, Anette; Hop, Haakon; Assmy, Phillipp (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-12)
      During the N-ICE2015 drift expedition north-west of Svalbard, we observed the establishment and development of algal communities in first-year ice (FYI) ridges and at the snow-ice interface. Despite some indications of being hot spots for biological activity, ridges are under-studied largely because they are complex structures that are difficult to sample. Snow infiltration communities can grow at ...
    • 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 ...
    • Alien species in Norway: results from quantitative ecological impact assessments 

      Sandvik, Hanno; Hilmo, Olga; Henriksen, Snorre; Elven, Reidar; Åsen, Per Arvid; Hegre, Hanne; Pedersen, Oddvar; Pedersen, Per Anker; Solstad, Heidi; Vandvik, Vigdis; Westergaard, Kristine Bakke; Ødegaard, Frode; Åström, Sandra Charlotte Helene; Elven, Hallvard; Endrestøl, Anders; Gammelmo, Øivind; Hatteland, Bjørn Arild; Solheim, Halvor; Nordén, Björn; Sundheim, Leif; Talgø, Venche; Falkenhaug, Tone; Gulliksen, Bjørn; Jelmert, Anders; Oug, Eivind; Sundet, Jan Henry; Forsgren, Elisabet; Finstad, Anders Gravbrøt; Hesthagen, Trygve H.; Nedreaas, Kjell Harald; Wienerroither, Rupert; Husa, Vivian; Fredriksen, Stein; Sjøtun, Kjersti; Steen, Henning; Hansen, Haakon; Hamnes, Inger Sofie; Karlsbakk, Egil; Magnusson, Christer; Ytrehus, Bjørnar; Pedersen, Hans Christian; Swenson, Jon; Syvertsen, Per Ole; Stokke, Bård Gunnar; Gjershaug, Jan Ove; Dolmen, Dag; Kjærstad, Gaute; Johnsen, Stein Ivar; Jensen, Thomas Correll; Hassel, Kristian; Gederaas, Lisbeth (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-20)
      1. Due to globalisation, trade and transport, the spread of alien species is increasing dramatically. Some alien species become ecologically harmful by threatening native biota. This can lead to irreversible changes in local biodiversity and ecosystem functioning, and, ultimately, to biotic homogenisation.<p><p> 2. We risk-assessed all alien plants, animals, fungi and algae, within certain ...
    • All-sky camera system providing high temporal resolution annual time series of irradiance in the arctic 

      Johnsen, Geir; Zolich, Artur; Grant, Stephen; Bjorgum, Rune; Cohen, Jonathan H.; Mckee, David; Kopec, Tomasz Piotr; Vogedes, Daniel Ludwig; Berge, Jorgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-23)
      The ArcLight observatory provides hourly continuous time series of light regime data (intensity, spectral composition, and photoperiod) from the Arctic, Svalbard at 79° N. Until now, no complete annual time series of biologically relevant light has been provided from the high Arctic due to insufficient sensitivity of commercial light sensors during the Polar Night. We describe a camera system providing ...
    • Allochthonous Allelopathy. Effects of Empetrum nigrum chemical interference on plant development 

      Pilsbacher, Anna Katharina (Master thesis; Mastergradsoppgave, 2016-05-20)
      The dwafshrub Empetrum nigrum uses phenolic compounds exuded by its leaves to depress the germination and growth of its surroundings. The allelopathic effect has, only been studied in areas immediately surrounding the plant (autochthonous allelopathy) but not in an open system apptoach that takes into account that a multitude of EMpetrum nigrum leaves get introduced into new environments through ...
    • Allometric trajectories of body and head morphology in three sympatric Arctic charr (Salvelinus alpinus (L.)) morphs 

      Simonsen, Marianne; Siwertsson, Anna; Adams, Colin Ean; Amundsen, Per-Arne; Præbel, Kim; Knudsen, Rune (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-08)
      A study of body and head development in three sympatric reproductively isolated Arctic charr (Salvelinus alpinus (L.)) morphs from a subarctic lake (Skogsfjordvatn, northern Norway) revealed allometric trajectories that resulted in morphological differences. The three morphs were ecologically assigned to a littoral omnivore, a profundal benthivore and a profundal piscivore, and this was confirmed ...
    • Altered regulation of TERMINAL FLOWER 1 causes the unique vernalisation response in an arctic woodland strawberry accession 

      Koskela, Elli A.; Kurokura, Takeshi; Toivainen, Tuomas; Sønsteby, Anita; Heide, Ola M; Sargent, Daniel J.; Isobe, Sachiko; Jaakola, Laura; Hilmarsson, Hrannar; Elomaa, Paula; Hytönen, Timo (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-16)
      <p>Vernalisation requirement is an agriculturally important trait that postpones the development of cold‐sensitive floral organs until the spring. The family Rosaceae includes many agriculturally important fruit and berry crops that suffer from crop losses caused by frost injury to overwintering flower buds. Recently, a vernalisation‐requiring accession of the Rosaceae model woodland strawberry ...
    • Alternative prey choice in the pteropod Clione limacina (Gastropoda) studied by DNA-based methods 

      Kallevik, Ida Helene Funderud (Master thesis; Mastergradsoppgave, 2013-11-15)
      The gymnosome pteropod Clione limacina is regarded as a monophagous predator, feeding exclusively on the thecosome pteropod Limacina helicina in Arctic waters. C. limacina is adapted to survive periods of low food availability by long-term starvation. Although L. helicina is absent from the water, a number of other zooplankton species are present during this time. It may therefore seem surprising ...
    • Ambient temperature effects on stress-induced hyperthermia in Svalbard ptarmigan 

      Nord, Andreas; Folkow, Lars (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-20)
      Stress-induced hyperthermia (SIH) is commonly observed during handling in homeotherms. However, in birds, handling in cold environments typically elicits hypothermia. It is unclear whether this indicates that SIH is differently regulated in this taxon or if it is due to size, because body temperature changes during handling in low temperatures have only been measured in small birds <0.03 kg (that ...
    • Ambient Temperature Effects on the Spring and Autumn Somatic Growth Trajectory Show Plasticity in the Photoneuroendocrine Response Pathway in the Tundra Vole 

      van Dalum, Mattis Jayme; van Rosmalen, Laura; Appenroth, Daniel; Cazarez Marquez, Fernando; Roodenrijs, Renzo T. M.; de Wit, Lauren; Hut, Roelof A.; Hazlerigg, David Grey (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-11)
      Seasonal mammals register photoperiodic changes through the photoneuroendocrine system enabling them to time seasonal changes in growth, metabolism, and reproduction. To a varying extent, proximate environmental factors like ambient temperature (Ta) modulate timing of seasonal changes in physiology, conferring adaptive flexibility. While the molecular photoneuroendocrine pathway governing the seasonal ...
    • The amphipod scavenging guild in two Arctic fjords : seasonal variations, abundance and trophic interactions 

      Nygård, Henrik Andreas; Berge, Jørgen; Søreide, Janne; Vihtakari, Mikko; Falk-Petersen, Stig (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      Scavenging amphipods are important for the circulation and dispersal of organic material in the marine environment. Despite their dominance in the scavenging guild and importance in the food web, little is known about Arctic amphipods and their feeding preferences. We studied the amphipod scavenging guild using baited traps for one full year to increase our understanding of its seasonal variations. ...
    • 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 ...
    • Analysing diet of small herbivores : the efficiency of DNA barcoding coupled with high-throughput pyrosequencing for deciphering the composition of complex plant mixtures 

      Valentini, Alice; Soininen, Eeva Marjatta; Coissac, Eric; Ims, Rolf Anker; Miquel, Christian; Yoccoz, Nigel Gilles; Gielly, Ludovic; Brochmann, Christian; Brysting, Anne K.; Sønstebø, Jørn H.; Taberlet, Pierre (Journal article; Tidsskriftartikkel; Peer reviewed, 2009-08-20)
      Background: In order to understand the role of herbivores in trophic webs, it is essential to know what they feed on. Diet analysis is, however, a challenge in many small herbivores with a secretive life style. In this paper, we compare novel (high-throughput pyrosequencing) DNA barcoding technology for plant mixture with traditional microhistological method. We analysed stomach contents of two ...
    • Analysis across diverse fish species highlights no conserved transcriptome signature for proactive behaviour 

      Rey, Sonia; Jin, Xingkun; Damsgård, Børge; Bégout, Marie-Laure; MacKenzie, Simon (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-07)
      <p>Background: Consistent individual differences in behaviour, known as animal personalities, have been demonstrated within and across species. In fish, studies applying an animal personality approach have been used to resolve variation in physiological and molecular data suggesting a linkage, genotype-phenotype, between behaviour and transcriptome regulation. In this study, using three fish species ...
    • Analysis of composition, morphology, and biosynthesis of cuticular wax in wild type bilberry (Vaccinium myrtillus L.) and its glossy mutant 

      Trivedi, Priyanka; Nguyen, Nga; Klavins, Linards; Kviesis, Jorens; Heinonen, Esa; Remes, Janne; Jokipii-Lukkari, Soile; Klavins, Maris; Karppinen, Katja; Jaakola, Laura; Häggman, Hely (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-09)
      In this study, cuticular wax load, its chemical composition, and biosynthesis, was studied during development of wild type (WT) bilberry fruit and its natural glossy type (GT) mutant. GT fruit cuticular wax load was comparable with WT fruits. In both, the proportion of triterpenoids decreased during fruit development concomitant with increasing proportions of total aliphatic compounds. In GT fruit, ...
    • An analysis of dietary variation in Icelandic arctic fox (Vulpes lagopus) over a period of 30 years using stable isotopes 

      Ellgutter, Jennifer Alejandrina Carbonell (Master thesis; Mastergradsoppgave, 2017-05-14)
      Identifying the food resources for a species is one of the basic steps towards understanding population dynamics. The arctic fox is the only terrestrial carnivore on Iceland, and the population had been increasing until recently. Therefore, it is of great importance to know what factors regulate the population growth and which resources support it to understand why the population fluctuates. In this ...
    • Analysis of xyloglucan-modifying genes and enzymes at graft-junctions of tomato plants 

      Lundblad, Herman (Master thesis; Mastergradsoppgave, 2020-05-16)
      Grafting is a widely used technique for propagation of plants in both agriculture and horticulture worldwide and involves combining two or more plants into one chimeric plant, ultimately with a shared vascular system. Benefits of grafting such as pathogen resistance, increase in fruit yield and abiotic stress tolerance have long been known, but the biological mechanisms of how plants graft are still ...