Artikler, rapporter og annet (arktisk og marin biologi): Nye registreringer

Viser treff 1461-1480 av 1636

    • The Effect of Freeze/Thaw Cycles on Reproducibility of Metabolic Profiling of Marine Microalgal Extracts Using Direct Infusion High-Resolution Mass Spectrometry (HR-MS) 

      Eilertsen, Hans Christian; Huseby, Siv; Degerlund, Maria; Eriksen, Gunilla Kristina; Ingebrigtsen, Richard Andre; Hansen, Espen (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-10-13)
      During normal sample preparation, storage in freezers and subsequent freeze/thaw cycles are commonly introduced. The effect of freeze/thaw cycles on the metabolic profiling of microalgal extracts using HR-MS was investigated. Methanolic extracts of monocultures of Arctic marine diatoms were analyzed immediately after extraction, after seven days of storage at −78 °C (one freeze/thaw cycle), and after ...

    • Identification Guide for Skates (Chondrichthyes: Rajiformes) in Norwegian waters, for both sexes and all stadiums 

      Lynghammar, Arve (Research report; Forskningsrapport, 2014-05)

    • Molecular characterization and phylogenetics of Fennoscandian cowpox virus isolates based on the p4c and atip genes 

      Okeke, Malachy Ifeanyi; Okoli, Arinze Stanley; Nilssen, Øivind; Moens, Ugo; Tryland, Morten; Bøhn, Thomas; Traavik, Terje (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      Background: Cowpox virus (CPXV), a rodent-borne Orthopoxvirus (OPV) that is indigenous to Eurasia can infect humans, cattle, felidae and other animals. Molecular characterization of CPXVs isolated from different geographic locations is important for the understanding of their biology, geographic distribution, classification and evolution. Our aim was to characterize CPXVs isolated from Fennoscandia ...

    • Phenology and cover of plant growth forms predict herbivore habitat selection in a high latitude ecosystem 

      Iversen, Marianne; Fauchald, Per; Langeland, Knut; Ims, Rolf Anker; Yoccoz, Nigel Gilles; Bråthen, Kari Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      The spatial and temporal distribution of forage quality is among the most central factors affecting herbivore habitat selection. Yet, for high latitude areas, forage quantity has been found to be more important than quality. Studies on large ungulate foraging patterns are faced with methodological challenges in both assessing animal movements at the scale of forage distribution, and in assessing ...

    • Use of unmanned aircraft systems (UAS) in a multi-scale vegetation index study of arctic plant communities in Adventdalen on Svalbard 

      Tømmervik, Hans; Karlsen, Stein-Rune; Nilsen, Lennart; Johansen, Bernt; Storvold, Rune; Zmarz, Anna; Beck, Pieter S.; Høgda, Kjell Arild; Goetz, Scott; Park, Taejin; Zagajewski, Bogdan; Myneni, Ranga B.; Bjerke, Jarle W. (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      Use of Unmanned Aircraft Systems (UAS) gives the opportunity to carry out research with a re-duced environmental footprint. Unmanned aircraft, including both fixed wing and multi rotor types (helicopters) allow us to collect very high resolution image data for vegetation mapping without the need for any personnel walking into the site and thereby potentially disturbing the sensitive Arctic ecosystems. ...

    • The relative effect of parasites and social status on sperm traits in Arctic charr 

      Figenschou, Lars; Folstad, Ivar; Rudolfsen, Geir; Hanssen, Sveinn Are; Kortet, Raine; Skau, Philip; Killie, Jan Eirik; Oskam, Irma Caroline; Strand, Harald (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Sperm production and sperm swimming speed, which most likely affect fertilization under sperm competition, are modified by proximate mechanisms. In a comprehensive observational study of free-living and reproductively active Arctic charr (Salvelinus alpinus), we examined the possible modulating effects of male social status (including ornamental development), parasite intensities, and immunity ...

    • Prolonged chemical restraint of walrus (Odobenus rosmarus) with etorphine supplemented with medetomidine 

      Griffiths, David; Born, Erik W.; Acquarone, Mario (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      Physiological studies involving the use of isotopic water required chemical restraint of free- ranging walruses (Odobenus rosmarus) for several hours. In August 2000, six male walrus (total body mass: 1050–1550 kg) were immobilized in East Greenland by remote delivery of 8.0–9.8 mg of etorphine and subsequently restrained for up to 6.75 h by administration of medetomidine. The effects of etorphine ...

    • Functional diversity of the Barents Sea fish community 

      Wiedmann, Magnus Aune; Aschan, Michaela; Certain, Gregoire; Dolgov, Andrey V.; Greenacre, Michael; Johannesen, Edda; Planque, Benjamin; Primicerio, Raul (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      This paper provides the first assessment of the functional diversity (FD) of the Barents Sea fish community. FD is recognized as an important driver of ecosystem functions and, thus, governs the adaptability of ecosystems in the face of disturbance. We integrate ecosystem survey data with an extensive trait matrix and show that fish FD displayed large spatial variation. The study period (2004 to ...

    • Evoked potentials in the Atlantic cod following putatively innocuous and putatively noxious electrical stimulation: a minimally invasive approach 

      Ludvigsen, Stian; Stenklev, Niels Chr.; Johnsen, Helge K.; Laukli, Einar; Matre, Dagfinn; Aas-Hansen, Øyvind (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Aspects of peripheral and central nociception have previously been studied through recording of somatosensory evoked potentials (SEPs) to putative noxious stimuli in specific brain regions in a few freshwater fish species. In the present study, we describe a novel, minimally invasive method for recording SEPs from the central nervous system of the Atlantic cod (Gadus morhua). Cutaneous ...

    • Hydrozoan diversity on hard bottom in Kongsfjorden, Svalbard 

      Voronkov, Andrey; Stepanjants, S.D.; Hop, Haakon (Journal article; Tidsskriftartikkel; Peer reviewed, 2010)
      Hydroids in Kongsfjorden, Svalbard, were studied on five hard-bottom transects along gradients of environmental conditions from the glacier at the fjord’s head to the fjord’s mouth at depth-range 0–30 m. Hydrozoa colonies are widely distributed on rock and gravel substrata in Kongsfjorden. In general, however, hydroids are not dominant or subdominant in zoobenthic communities. The exception is ...

    • The Atlantic spiny lumpsucker Eumicrotremus spinosus: life history traits and the seemingly unlikely interaction with the pelagic amphipod Themisto libellula 

      Berge, Jørgen; Nahrgang, Jasmine (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      During a cruise to Svalbard in September 2012 a unique collection of the little known but widely distributed Atlantic spiny lumpsucker (Eumicrotremus spinosus) was made in the Hinlopen Strait. A total of 140 individuals (36–101mm total length) were col− lected using a bottom trawl. All individuals were sexed and 26 of these were also analysed for gonadosomatic index (GSI), hepatosomatic index ...

    • Lipid Status of the Two High Latitude Fish Species, Leptoclinus maculatus and Lumpenus fabricii 

      Murzina, Svetlana A.; Nefedova, Zinaida A.; Falk-Petersen, Stig; Ripatti, Pauli O.; Ruokolainen, Tatiana R.; Pekkoeva, Svetlana N.; Nemova, Nina N. (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      A comparative study of the lipid status (i.e., the total lipid and phospholipid concentrations and the percentage of fatty acids of the total lipids) of adult specimens of daubed shanny (Leptoclinus maculatus) from Svalbard waters (Isfjord) and slender eel blenny (Lumpenus fabricii) from the White Sea (Onega Bay and Tersky shore) was performed to study the metabolism and functions of lipids of these ...

    • No longer tracking greenery in high altitudes: Pastoral practices of Rupshu nomads and their implications for biodiversity conservation 

      Singh, Navinder; Bhatnagar, Yash Veer; Lecomte, Nicolas; Fox, Joseph L.; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Nomadic pastoralism has thrived in Asia’s rangelands for several millennia by tracking seasonal changes in forage productivity and coping with a harsh climate. This pastoralist lifestyle, however, has come under intense transformations in recent decades due to socio-political and land use changes. One example is of the high-altitude trans-Himalayan rangelands of the Jammu and Kashmir State in ...

    • Recent oceanic changes in the Arctic in the context of long-term observations 

      Polyakov, Igor V; Bhatt, Uma; Walsh, John E.; Abrahamsen, Einar Povl; Pnyushkov, A.V.; Wassmann, Paul (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      This synthesis study assesses recent changes of Arctic Ocean physical parameters using a unique collection of observations from the 2000s and places them in the context of long-term climate trends and variability. Our analysis demonstrates that the 2000s were an exceptional decade with extraordinary upper Arctic Ocean freshening and intermediate Atlantic water warming. We note that the Arctic ...

    • Diversity of hard-bottom fauna relative to environmental gradients in Kongsfjorden, Svalbard 

      Voronkov, Andrey; Hop, Haakon; Gulliksen, Bjørn (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      A baseline study of hard-bottom zoobenthos in relation to environmental gradients in Kongsfjorden, a glacial fjord in Svalbard, is presented, based on collections from 1996 to 1998. The total species richness in 62 samples from 0 to 30 m depth along five transects was 403 species. Because 32 taxa could not be identified to species level and because 11 species are probably new to science, the ...

    • How rapidly do invasive birch forest geometrids recruit larval parasitoids? Insights from comparison with a sympatric native geometrid 

      Laksforsmo Vindstad, Ole Petter; Schott, Tino; Hagen, Snorre; Jepsen, Jane Uhd; Kapari, Lauri Teemu; Ims, Rolf Anker (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Two related issues in studies of biological invasions are how quickly the enemy complexes of invasive species become as species-rich and efficient as those of native species and how important enemy release is for the establishment and spread of invaders. We addressed these issues for the geometrid moths Operophtera brumata and Agriopis aurantiaria, who invaded the coastal mountain birch forest ...

    • Seasonal patterns in Arctic planktonic metabolism (Fram Strait - Svalbard region) 

      Vaquer-Sunyer, Raquel; Duarte, Carlos M.; Regaudie-de-Gioux, A; Holding, Johnna; García-Corral, LS; Reigstad, Marit; Wassmann, Paul (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The metabolism of the Arctic Ocean is marked by extremely pronounced seasonality and spatial heterogeneity associated with light conditions, ice cover, water masses and nutrient availability. Here we report the marine planktonic metabolic rates (net community production, gross primary production and community respiration) along three different seasons of the year, for a total of eight cruises ...

    • Warming of Atlantic Water in two west Spitsbergen fjords over the last century (1912-2009) 

      Pavlov, Alexey K.; Tverberg, Vigdis; Ivanov, Boris; Nilsen, Frank; Falk-Petersen, Stig; Granskog, Mats A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The recently observed warming of west Spitsbergen fjords has led to anomalous sea-ice conditions and has implications for the marine ecosystem. We investigated long-term trends of maximum temperature of AtlanticWater (AW) in two west Spitsbergen fjords. The data set is composed of more than 400 oceanographic stations for Isfjorden and Grønfjorden (78.18N), spanning from 1876 to 2009. Trends ...

    • Trace elements and cathodoluminescence of detrital quartz in Arctic marine sediments - a new ice-rafted debris provenance proxy 

      Muller, A; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The records of ice-rafted debris (IRD) provenance in the North Atlantic–Barents Sea allow the reconstruction of the spatial and temporal changes of ice-flow drainage patterns during glacial and deglacial periods. In this study a new approach to characterization of the provenance of detrital quartz grains in the fraction > 500 μm of marine sediments offshore of Spitsbergen is introduced, utilizing ...

    • Outbreaks by canopy-feeding geometrid moth cause state-dependent shifts in understorey plant communities 

      Karlsen, Stein Rune; Jepsen, Jane Uhd; Odland, Arvid; Ims, Rolf Anker; Elvebakk, Arve (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The increased spread of insect outbreaks is among the most severe impacts of climate warming predicted for northern boreal forest ecosystems. Compound disturbances by insect herbivores can cause sharp transitions between vegetation states with implications for ecosystem productivity and climate feedbacks. By analysing vegetation plots prior to and immediately after a severe and widespread ...