Blar i tittel Mastergradsoppgaver i biologi
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Impacts of water level regulation on trophic niche and growth of Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) in Norwegian hydropower reservoirs
(Master thesis; Mastergradsoppgave, 2019-05-15)Hydropower is among the largest renewable energy sources globally. However, it can have drastic environmental and socio-economic impacts on dammed lakes (i.e., reservoirs) and rivers where water levels are regulated due to hydropower operations. Water level regulation in hydropower reservoirs is known to be a large environmental problem, leading to changes in the abiotic conditions, which subsequently ... -
The Importance of Morphological/Physiological Heterogeneity as Adaptive Strategies in Stocks of Common Northern/Arctic Phytoplankton Species with Special Focus on the Common Diatom Chaetoceros socialis
(Master thesis; Mastergradsoppgave, 2006-12-13)The cosmopolitan, centric diatom Chaetoceros socialis was investigated in terms of its validity as a single species characterized by its morphology, physiology and distribution. A database was constructed using my own and published literature distribution observations of C. socialis in Northern Norway, the Atlantic, Arctic and Barents Sea. From this range of observations, it is possible to establish ... -
In Silico Screening for inhibitors against Apicoplast Phosphate Translocator from Toxoplama gondii
(Master thesis; Mastergradsoppgave, 2019-05-16)Apicomplexa parasites, including Toxoplasma gondii and Plasmodium falciparum, contain a secondary endosymbiosis-derived plastid like organ, called apicoplast, which is an anabolic hub. This apicoplast is fueled by phosphate translocator (APT), which transport phosphorylated sugar molecules in exchange of inorganic phosphate. Disruption of APT in T. gondii was found to be lethal for parasite. Beside ... -
Infectious agents involved in infectious keratoconjunctivitis in semi-domesticated reindeer (Rangifer tarandus tarandus) in Fennoscandia.
(Master thesis; Mastergradsoppgave, 2015-11-12)Infectious keratoconjunctivitis (IKC) is one of the most common ocular diseases in ruminants worldwide. Animals affected by this disease can show a wide variety of clinical symptoms, including keratitis, uveitis, corneal ulcer, conjunctivitis and in severe cases, blindness. Moraxella spp., Chlamydia spp. and Mycoplasma conjunctivae have been described as primary causative agents in ruminant species ... -
Inflammatory responses in lumpfish (Cyclopterus lumpus L.) vaccinated at different water temperatures with intraperitoneal injection
(Master thesis; Mastergradsoppgave, 2021-05-18)The use of lumpfish (Cyclopterus lumpus L.) as cleaner fish in salmonid aquaculture for the biological control of sea lice infestation levels has increased in recent years. The species is relatively new to aquaculture and susceptible to various infectious agents. The health situation for lumpfish is currently considered poor, indicating the necessity for developing more efficient vaccines. Studying ... -
The influence of herring (Clupea harengus) biomass and distribution on killer whale (Orcinus orca) movements on the Norwegian shelf
(Master thesis; Mastergradsoppgave, 2020-06-01)Killer whales (Orcinus orca) have a cosmopolitan distribution with a broad diet ranging from fish to marine mammals. Regional populations show local prey specialization and their movements are tightly linked to those of their prey. Norwegian killer whales are known to feed extensively on Norwegian spring spawning (NSS) herring (Clupea harengus). Over the last decade, killer whales have begun to ... -
Influence of photoperiod on central appetite regulation in captive Svalbard rock ptarmigan (Lagopus muta hyperborea)
(Master thesis; Mastergradsoppgave, 2018-08-09)The Svalbard rock ptarmigan displays a seasonal change of body mass as a selectively beneficial adaptation for survival in the high Arctic. This physiological change is sensitive to photoperiod (daylight duration in a 24h cycle) but little is known of the mechanism through which changes in photoperiod affects body mass in this species. We exposed winer adapted Sv. rock ptarmigan to a simulated ... -
Ingestion and egestion of microplastic fibers in the green sea urchin Strongylocentrotus droebachiensis: An experimental exposure
(Master thesis; Mastergradsoppgave, 2021-05-18)Plastic is a major component of marine litter in the world’s oceans and therefore it is critical we develop a better understanding of the fate of plastic in the marine environment, and the potential impacts on biota. Microplastics are the most abundant size class (<5 mm) of plastic found in the marine environment and have the potential to interact with smaller marine organisms at lower trophic levels. ... -
Initial Community Convergence on Plant Defense Syndromes Explains Community Responses to Herbivore Exclosures
(Master thesis; Mastergradsoppgave, 2017-11-15)General trade-offs in species’ energy use are highlighted here by mapping proposed defense syndromes, using trade-offs found between: constitutive phenolic compounds, silica and a high nutrient low defense region found between regional con-specifics. Differences in species composition between two catchments can be explained by proposed syndrome trade-offs seeking energy use optimums in differing ... -
Initielle studier av Mll3104 og Mll3105 fra Mesorhizobium loti : proteiner antatt involvert i katabolisme av trehalose
(Master thesis; Mastergradsoppgave, 2007-12)Rhizobiacea utgjør en bakterieslekt der de fleste medlemmene er i stand til å inngå symbioser med diverse legumer. Slekten innbefatter Rhizobium, Sinorhizobium, Mesorhizobium, Bradyrhizobium og Azorhizobium, og kollektivt omtales disse for rhizobia. Partnerskapet med legumer er av mutualistisk karakter, der mikrosymbionten bidrar med fiksert nitrogen i form av NH3, og planteverten sørger for en ... -
Interactions between white-tailed eagle Haliaeetus albicilla, seabirds and tourism; how the breeding success of the endangered black-legged kittiwake Rissa tridactyla is affected
(Master thesis; Mastergradsoppgave, 2021-12-17)In many seabird colonies along the coast of Norway, the increased population of white-tailed eagle Haliaeetus albicilla and the growing industry of birdwatching tourism are causing a dilemma for management decisions. Thus, this study aimed to examine the indirect effect of white-tailed eagles and tourists on the breeding success of the endangered seabird species, black legged kittiwake Rissa tridactyla ... -
An interannual study of foraging behaviour in sympatrically breeding macaroni Eudyptes chrysolophus and chinstrap penguins Pygoscelis antarcticus at Bouvetøya
(Master thesis; Mastergradsoppgave, 2019-08-15)Species are likely to segregate their ecological niches to minimize competition for resources, but for centrally foraging predators that breed on sub-Antarctic islands in the Southern Ocean the possibility of niche segregation may be minimal. This study is the first to examine the spatial and trophic aspects of the foraging niche of sympatrically breeding macaroni and chinstrap penguins at the ... -
Interannual variability (2014-2019) of hydrography, fluorescence and nutrient distribution in Vestfjorden, Lofoten
(Master thesis; Mastergradsoppgave, 2020-06-01)Vestfjorden is an area of great ecological relevance since it is one of the main spawning areas of North East Atlantic cod. The survival rate of the cod larvae depends greatly on the abundance of zooplankton, which in turn depends on phytoplankton. Due to the extreme seasonality of high latitude fjords with a short productive season, understanding the phytoplankton distribution in spring is crucial. ... -
Investigating population genomic structure of salmon lice (Lepeophtheirus salmonis) in northern Norway
(Master thesis; Mastergradsoppgave, 2019-05-14)Salmon louse (Lepeophtheirus salmonis) is a parasitic copepod that causes significant damage to Atlantic salmon (Salmo salar) and incurs significant costs to the salmonid aquaculture industry. In Norway, the industry has been coping with salmon lice issues with various methods such as chemical treatments, but it has resulted in an acquisition of resistance in salmon lice towards the existing delousing ... -
Isolation of Fungal Endophytes from Grasses by Laser Micro Dissection & Pressure Catapulting
(Master thesis; Mastergradsoppgave, 2013-12-12)A very diverse group of fungi capable of forming endophytic associations may have profound consequences for natural ecosystems as well as for cultivated plants. Fungal endophytes may benefit their host plants by producing secondary metabolites, and may be an important source for bioactive antimicrobial compounds, used in agriculture, commercial industry, and in medicine. Earlier studies on endophytes ... -
Kjønnsspesifikk overlevelse av unger hos gråmåke Larus argentatus og svartbak Larus marinus
(Master thesis; Mastergradsoppgave, 2008-03)Det er i dag gode bevis for at fugler har muligheter til å endre kjønn på avkom kjønns ratio) i forhold til en rekke miljøfaktorer. Dette kan skje enten ved at de produserer et overskudd av egg med unger av det ønskede kjønn (primær kjønns ratio), eller at de manipulerer kjønns ratio etter klekking ved å differensiere innvesteringa (eks. mating) i favør av det ene kjønnet sekundær kjønns ratio). ... -
Klimaeffekter på frøspiring og blomstring hos svalbardvalmue (Papaver dahlianum Nordh.)
(Master thesis; Mastergradsoppgave, 2007-05)Det ble gjennomført klimakammerforsøk på arten Papaver dahlianum, for å undersøke i hvilken grad klima påvirker frøspiring og blomstring hos avkommet. Høsten 2005 ble frø av Papaver dahlianum polare samlet rundt Longyearbyen og i Arktisk-alpin botanisk hage i Tromsø. Plantene i botanisk hage stammet også fra Svalbard, men ble sådd i Tromsø i 2002. Forsøkene ble utført ved Biologisk klimalaboratorium ... -
Langtidsstudie av næringsøkologi og vekst hos storørret i Pasvikvassdraget - en sammenligning mellom utsatt og vill ørret
(Master thesis; Mastergradsoppgave, 2014-05-15)Kraftutbyggingen i Pasvikvassdraget startet i 1964 og det finnes syv kraftverk i vassdraget. Storørretbestanden gikk kraftig tilbake som følge av kraftutbyggingen og i 1979 ble det startet et utsettingsprogram av ørret i elva for å kompensere for reduksjonen i størrelsen av den naturlige populasjonen. I dag settes det årlig ut 5000 ørret større enn 25 cm. Dette langtidsstudiet omhandler diett og ... -
Let it glow! Adapting a method to detect microplastics in snow and evaluate the potential for long-range transport
(Master thesis; Mastergradsoppgave, 2020-05-31)Harmonization of methods in microplastics research is lacking; this is affecting the comparability of results and hindering reproducibility. Investigating microplastics in snow is a relatively new field of research, and it can be used to answer questions about long-range atmospheric transport of microplastics. In this thesis, snow sampling methods were combined with the dye, Nile Red, to develop a ... -
Life history strategies of a trimorphic population of Arctic charr (Salvelinus alpinus (L.)) in Skogsfjordvatn, northern-Norway
(Master thesis; Mastergradsoppgave, 2013-05-15)Polymorphisms are widespread throughout many different taxa of vertebrates. Discrete polymorphisms or morphs usually differentiate in morphology, ecology and life history, most likely driven by adaptations to different habitats and resources. For sympatric morphs to be able to maximize fitness in different niches and habitats, they may develop differences in several life history traits. Arctic charr ...