Now showing items 61-80 of 2012

    • Melatonin and Seasonal Synchrony in Mammals 

      Hazlerigg, David Grey; Simonneaux, Valérie; Dardente, Hugues (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-12)
      In mammals, seasonal opportunities and challenges are anticipated through programmed changes in physiology and behavior. Appropriate anticipatory timing depends on synchronization to the external solar year, achieved through the use of day length (photoperiod) as a synchronizing signal. In mammals, nocturnal production of melatonin by the pineal gland is the key hormonal mediator of photoperiodic ...
    • Exploring the effects of methodological choices on the estimation and biological interpretation of life history parameters for harbour porpoises in Norway and beyond 

      Frie, Anne Kirstine Højholt; Lindstrøm, Ulf Ove (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-15)
      This study investigates effects of subtle methodological choices on the estimation and biological interpretation of age, growth and reproductive parameters for harbour porpoises. The core analyses are based on a focal Norwegian data set built on samples from 134 harbour porpoises caught incidentally in gillnet fisheries along the Norwegian coast during autumn 2016 and spring 2017. Two contrasting ...
    • Targeting methanotrophs and isolation of a novel psychrophilic Methylobacter species from a terrestrial Arctic alkaline methane seep in Lagoon Pingo, Central Spitsbergen (78° N) 

      Patil, Shalaka Kiran; Islam, Tajul; Tveit, Alexander Tøsdal; Hodson, Andrew; Øvreås, Lise (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-22)
      The microbial diversity associated with terrestrial groundwater seepage through permafrost soils is tightly coupled to the geochemistry of these fluids. Terrestrial alkaline methane seeps from Lagoon Pingo, Central Spitsbergen (78°N) in Norway, with methane-saturated and oxygen-limited groundwater discharge providing a potential habitat for methanotrophy. Here, we report on the microbial community’s ...
    • Physiological basis for atmospheric methane oxidation and methanotrophic growth on air 

      Schmider, Tilman John Siegfried; Hestnes, Anne Grethe; Brzykcy, Julia; Schmidt, Hannes; Schintlmeister, Arno; Roller, Benjamin; Teran, Ezequiel Jesús; Söllinger, Andrea; Schmidt, Oliver; Polz, Martin; Richter, Andreas; Svenning, Mette Marianne; Tveit, Alexander Tøsdal (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-16)
      Atmospheric methane oxidizing bacteria (atmMOB) constitute the sole bio-logical sink for atmospheric methane. Still, the physiological basis allowing atmMOB to grow on air is not well understood. Here we assess the ability and strategies of seven methanotrophic species to grow with air as sole energy, carbon, and nitrogen source. Four species, including three outside the canonical atmMOB group USCα, ...
    • Essential omega-3 fatty acids are depleted in sea ice and pelagic algae of the Central Arctic Ocean 

      Schmidt, Katrin; Graeve, Martin; Hoppe, Clara J. M.; Torres-Valdes, Sinhué; Welteke, Nahid; Whitmore, Laura M.; Anhaus, Philipp; Atkinson, Angus; Belt, Simon T.; Brenneis, Tina; Campbell, Robert G.; Castellani, Giulia; Copeman, Louise A.; Flores, Hauke; Fong, Allison A.; Hildebrandt, Nicole; Kohlbach, Doreen; Nielsen, Jens M.; Parrish, Christopher C.; Rad-Menéndez, Cecilia; Rokitta, Sebastian D.; Tippenhauer, Sandra; Zhuang, Yanpei (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-19)
      Microalgae are the main source of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), essential for the healthy development of most marine and terrestrial fauna including humans. Inverse correlations of algal EPA and DHA proportions (% of total fatty acids) with temperature have led to suggestions of a warming-induced decline in the global production of these biomolecules ...
    • Overview of the MOSAiC expedition: Ecosystem 

      Fong, Allison A.; Hoppe, Clara J. M.; Aberle, Nicole; Ashjian, Carin; Assmy, Philipp Kurt Wolf; Bai, Youcheng; Bakker, Dorothee C. E.; Balmonte, John Paul; Barry, Kevin; Bertilsson, Stefan; Boulton, William; Bowman, Jeff; Bozzato, Deborah; Bratbak, Gunnar; Buck, Moritz; Campbell, Robert G.; Castellani, Giulia; Chamberlain, Emelia J.; Chen, Jianfang; Chierici, Melissa; Cornils, Astrid; Creamean, Jessie; Damm, Ellen; Dethloff, Klaus; Droste, Elise S.; Ebenhöh, Oliver; Eggers, Sarah Lena; Engel, Anja; Flores, Hauke; Fransson, Agneta; Frickenhaus, Stephan; Gardner, Jessie; Gelfman, Cecilia E.; Granskog, Mats; Graeve, Martin; Havermans, Charlotte; Heuzé, Céline; Hildebrandt, Nicole; Hill, Thomas C. J.; Hoppema, Mario; Immerz, Antonia; Jin, Haiyan; Koch, Boris P.; Kong, Xianyu; Kraberg, Alexandra C.; Lan, Musheng; Lange, Benjamin Allen; Larsen, Aud; Lebreton, Benoit; Leu, Eva Susanne; Loose, Brice; Maslowski, Wieslaw; Mavis, Camille; Metfies, Katja; Mock, Thomas; Müller, Oliver; Marcel, Nicolaus; Niehoff, Barbara; Nomura, Daiki; Nöthig, Eva-Maria; Oggier, Marc; Oldenburg, Ellen; Olsen, Lasse Mork; Peeken, Ilka; Perovich, Donald K.; Popa, Ovidiu; Rabe, Benjamin; Ren, Jian; Rex, Markus; Rinke, Annette; Rokitta, Sebastian; Rost, Björn; Sakinan, Serdar S.; Salganik, Evgenii; Schaafsma, Fokje L.; Schäfer, Hendrik; Schmidt, Katrin; Shoemaker, Katyanne; Shupe, Matthew D.; Snoeijs-Leijonmalm, Pauline; Stefels, Jacqueline; Svenson, Anders; Tao, Ran; Sinhué, Torres-Valdés; Torstensson, Anders; Toseland, Andrew; Ulfsbo, Adam; Leeuwe, Maria A. van; Vortkamp, Martina; Webb, Alison L.; Zhuang, Yanpei; Gradinger, Rolf Rudolf (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-21)
      The international and interdisciplinary sea-ice drift expedition “The Multidisciplinary drifting Observatory for the Study of Arctic Climate” (MOSAiC) was conducted from October 2019 to September 2020. The aim of MOSAiC was to study the interconnected physical, chemical, and biological characteristics and processes from the atmosphere to the deep sea of the central Arctic system. The ecosystem team ...
    • Governance for Earth system tipping points – A research agenda 

      Milkoreit, Manjana; Boyd, Emily; Constantino, Sara M.; Hausner, Vera Helene; Hessen, Dag Olav; Kääb, Andreas; McLaren, Duncan; Nadeau, Christina; O'Brien, Karen; Parmentier, Frans-Jan W.; Rotbarth, Ronny; Rødven, Rolf; Treichler, Désirée; Rowe, Elana Tovah Wilson; Yamineva, Yulia (Journal article; Tidsskriftartikkel, 2024-06-12)
      Tipping points in the Earth system could be passed within the Paris Agreement's temperature goal range (1.5°C–2°C). Tipping processes are a feature of complex Earth system dynamics that present major governance challenges not addressed by existing global governance institutions. The common governance toolkit is a poor match for dealing with tipping processes, especially non-linear change, and radical ...
    • Feeding ecology of age-0 polar cod (Boreogadus saida) in the Greenland Sea 

      Klasmeier, Apasiri (Master thesis; Mastergradsoppgave, 2024-08-15)
      Polar cod (Boreogadus saida) play a crucial role as a key species in Arctic marine ecosystems. The importance of successful feeding of particularly their sensitive early life stages for survival and later recruitment into the adult population is known. This study investigated the diets of age-0 polar cod in the Greenland Sea (Northeast Greenland) during the summer and fall of 2017, focusing on ...
    • Singers of the High Arctic; Seasonal acoustic presence of Spitsbergen bowhead whales (Balaena mysticetus) around Svalbard, Norway 

      Wams, Luca (Master thesis; Mastergradsoppgave, 2024-08-15)
      Marine mammals throughout the circumpolar Arctic are facing profound levels of environmental change due to climate warming. Among them is the bowhead whale (Balaena mysticetus), an Arctic endemic cetacean that spends its entire life in Arctic waters and lives in tight association with sea ice habitats. The Spitsbergen bowhead whale population resides in the Northeast Atlantic, where they were hunted ...
    • Foraging Behavior of Chinstrap Penguins (Pygoscelis antarctica) at the South Orkney Islands (Antarctica) during their Breeding Season 

      Rusch, Marie (Master thesis; Mastergradsoppgave, 2024-08-14)
      Chinstrap penguins (Pygoscelis antarctica) are central place foragers during their breeding season in the austral summer, which restricts the distance and duration they can forage away from their chicks. Recent studies indicate a regional decline in chinstrap penguin populations across their distribution range. During breeding, they almost exclusively feed on Antarctic krill (Euphausia superba), a ...
    • Efficacy, persistence and residue levels of fungicides for Botrytis control in wild blueberry 

      Abbey, Joel; Percival, David; Jaakola, Laura Elina; Asiedu, Samuel K. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-02-17)
      Botrytis blossom blight disease is one of the major challenges to wild blueberry production with annual losses frequently exceeding 20%. In this study, the effect of different fungicide treatments on Botrytis blight development and yield, as well as the mobility and persistence of these fungicides within flower tissues, and fruit of wild blueberries were evaluated under field conditions. This ...
    • Bacterioplankton taxa compete for iron along the early spring–summer transition in the Arctic Ocean 

      Puente-Sánchez, Fernando; Macías-Pérez, Luis Alberto; Campbell, Karley Lynn; Royo-Llonch, Marta; Balagué, Vanessa; Sánchez, Pablo; Tamames, Javier; Mundy, Christopher John; Pedrós-Alió, Carlos (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-18)
      Microbial assemblages under the sea ice of the Dease Strait, Canadian Arctic, were sequenced for metagenomes of a small size fraction (0.2–3 μm). The community from early March was typical for this season, with Alpha- and Gammaproteobacteria as the dominant taxa, followed by Thaumarchaeota and Bacteroidetes. Toward summer, Bacteroidetes, and particularly the genus Polaribacter, became increasingly ...
    • Mapping Potential Timing of Ice Algal Blooms From Satellite 

      Stroeve, J.C.; Veyssiere, G.; Nab, C.; Light, B.; Perovich, D.; Laliberté, J.; Campbell, Karley Lynn; Landy, Jack Christopher; Mallett, Robbie David Christopher; Barrett, A; Liston, G.E.; Haddon, A.; Wilkinson, J. (Journal article; Tidsskriftartikkel, 2024-04-17)
      As Arctic sea ice and its overlying snow cover thin, more light penetrates into the ice and upper ocean, shifting the phenology of algal growth within the bottom of sea ice, with cascading impacts on higher trophic levels of the Arctic marine ecosystem. While field data or autonomous observatories provide direct measurements of the coupled sea ice-algal system, they are limited in space and time. ...
    • Path analysis reveals combined winter climate and pollution effects on the survival of a marine top predator 

      Layton-Matthews, Kate; Erikstad, Kjell E.; Sandvik, Hanno; Ballesteros, Manuel; Hodges, Kevin; Mesquita, Michel d. S.; Reiertsen, Tone Kristin; Yoccoz, Nigel Gilles; Bustnes, Jan Ove (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-06)
      Marine ecosystems are experiencing growing pressure from multiple threats caused by human activities, with far-reaching consequences for marine food webs. Determining the effects of multiple stressors is complex, in part, as they can affect different aspects of biological organisation (behaviour, individual traits and demographic rates). Determining the combined effects of stressors, through different ...
    • The Eurasian Arctic Ocean along the MOSAiC drift in 2019–2020: An interdisciplinary perspective on physical properties and processes 

      Schulz, Kirstin; Koenig, Zoe Charlotte; Muilwijk, Morven; Bauch, Dorotea; Hoppe, Clara J.M.; Droste, Elise S.; Hoppmann, Mario; Chamberlain, Emelia J.; Laukert, Georgi; Stanton, Tim; Quintanilla-Zurita, Alejandra; Fer, Ilker; Heuzé, Céline; Karam, Salar; Mieruch-Schnülle, Sebastian; Baumann, Till Martin; Vredenborg, Myriel; Tippenhauer, Sandra; Granskog, Mats (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-05)
      The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC, 2019–2020), a year-long drift with the Arctic sea ice, has provided the scientific community with an unprecedented, multidisciplinary dataset from the Eurasian Arctic Ocean, covering high atmosphere to deep ocean across all seasons. However, the heterogeneity of data and the superposition of spatial and temporal ...
    • Panel-based assessment of ecosystem condition as a platform for adaptive and knowledge driven management 

      Jepsen, Jane Uhd; Arneberg, Per; Ims, Rolf Anker; Siwertsson, Anna; Yoccoz, Nigel Gilles; Fauchald, Per; Pedersen, Åshild Ønvik; van der Meeren, Gro Ingleid; von Quillfeldt, Cecilie H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-09-13)
      Ecosystems are subjected to increasing exposure to multiple anthropogenic drivers. This has led to the development of national and international accounting systems describing the condition of ecosystems, often based on few, highly aggregated indicators. Such accounting systems would benefit from a stronger theoretical and empirical underpinning of ecosystem dynamics. Operational tools for ecosystem ...
    • Herbivore diversity effects on Arctic tundra ecosystems: a systematic review 

      Barbero-Palacios, Laura; Barrio, Isabel C.; García Criado, Mariana; Kater, Ilona; Petit Bon, Matteo; Kolari, Tiina H. M.; Bjørkås, Ragnhild; Trepel, Jonas; Lundgren, Erick; Björnsdóttir, Katrín; Hwang, Bernice C.; Bartra Cabre, Laura; Defourneaux, Mathilde; Ramsay, Jennifer; Lameris, Thomas K.; Leffler, A. Joshua; Lock, Janine G.; Kuoppamaa, Mari S.; Kristensen, Jeppe A.; Bjorkman, Anne D.; Myers-Smith, Isla; Lecomte, Nicolas; Axmacher, Jan C.; Den Herder, Michael; Pagneux, Emmanuel P.; Skarin, Anna; Sokolova, Natalia; Windirsch, Torben; Wheeler, Helen Claire; Serrano, Emmanuel; Virtanen, Tarmo; Hik, David S.; Kaarlejärvi, Elina; Speed, James David Mervyn; Soininen, Eeva M; Gilg, Olivier (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-25)
      Background Northern ecosystems are strongly influenced by herbivores that differ in their impacts on the eco‑ system. Yet the role of herbivore diversity in shaping the structure and functioning of tundra ecosystems has been overlooked. With climate and land-use changes causing rapid shifts in Arctic species assemblages, a better under‑ standing of the consequences of herbivore diversity changes for ...
    • Changing species dominance patterns of Boreal-Arctic heathlands: evidence of biotic homogenization 

      Bråthen, Kari Anne; Tuomi, Maria Wilhelmina; Kapfer, Jutta; Böhner, Hanna; Maliniemi, Tuija (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-29)
      Heathlands are extensive systems often dominated by slow-growing and long-lived woody plants. These systems require longer-term studies to capture if and how they are changing over time. In 2020, we resurveyed species richness and cover of vascular plant communities in 139 heathlands along the coastline of northern Fennoscandia, first surveyed during 1965–1975. The first survey included six ...
    • Camera traps reveal seasonal variation in activity and occupancy of the Alpine mountain hare Lepus timidus varronis 

      Bison, Marjorie; Yoccoz, Nigel Gilles; Carlson, Bradley Z.; Bayle, Arthur; Delestrade, Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-01)
      Mountain hare is a cold-adapted species threatened by climate change, but despite its emblematic nature, our understanding of the causes of population decline remains limited. Camera traps are increasingly used in ecology as a tool for monitoring animal populations at large spatial and temporal scales. In mountain environments where field work is constrained by difficult access and harsh ...
    • Taxonomic and functional-trait metrics track recovery of demersal fish and shrimp communities following system collapse 

      Wiedmann, Magnus Aune; Ramasco, Virginie; Wells, Nadine; Warren, Margaret; Cyr, Frédéric; Pedersen, Eric J.; Koen-Alonso, Mariano; Eriksen, Elena; Primicerio, Raul; Lindstrøm, Ulf Ove; Renaud, Paul Eric (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-11)
      Monitoring programs that integrate both structural and functional ecosystem components play integral roles in ecosystem management and conservation planning. In the early 1990’s, the marine ecosystem of the waters surrounding Newfoundland and Labrador (NL) underwent a regime shift. Several demersal and pelagic fish stocks collapsed simultaneously, and this had significant ecological and socioeconomic ...