Viser treff 41-60 av 276

    • The use of stated preferences and bio-economic modeling in marine ecosystem service management: Case studies from Arctic Norway 

      Ahi, Julide Ceren (Doctoral thesis; Doktorgradsavhandling, 2022-06-09)
      <p>Regarding the growing population and escalated development on the coasts, the environmental policymakers often face the dilemma of exploiting or protecting marine and coastal ecosystem services (ES). Therefore, the non-market valuation has become an essential instrument for supporting policymakers in eliciting preferences and welfare estimates regarding various ES, which further feed into the ...
    • Population cycles in small rodents seen through the lens of a wildlife camera 

      Kleiven, Eivind Flittie (Doctoral thesis; Doktorgradsavhandling, 2022-06-08)
      Population cycles in small rodents have attracted attention from ecologists for more than a century. This spectacular phenomenon is crucial for the functioning of many northern food-webs and has intrigued ecologist because of its lessons for general ecology. Knowledge about the rodent cycle has, however, been hampered by the lack of reliable monitoring methods both for rodents and some of their ...
    • Economic valuation of climate change impacts on ecotourism in Rekawa coastal wetland in Sri Lanka: Application of stated preference techniques 

      Salpage, Nesha Dushani (Doctoral thesis; Doktorgradsavhandling, 2022-06-02)
      <p>The research presented in this thesis has focused on the economic valuation of climate change impacts on ecotourism in a coastal wetland using three different methods of stated-preference techniques to provide answers to different research questions related to coastal tourism and climate change. Rekawa coastal wetland in Southern Sri Lanka was taken as the empirical context to examine the identified ...
    • Tundra vegetation ecology from the sky - Aerial images and photogrammetry as tools to monitor landscape change 

      Eischeid, Isabell (Doctoral thesis; Doktorgradsavhandling, 2022-05-24)
      Long-term temperature increases, higher frequencies of extreme weather events and changes in food web structures will all affect the state of Arctic tundra ecosystems at different temporal and spatial scales. Ecologists are tasked with understanding these biotic and abiotic interactions and finding methods to measure them. This thesis applies new technology and methods within the principles of ...
    • How to tame a parasite - Developing biotechnological pipelines for gene function studies in Cuscuta 

      Lachner, Lena Anna-Maria (Doctoral thesis; Doktorgradsavhandling, 2022-05-20)
      <p><i>Cuscuta</i> is a genus of parasitic plants that form cross-species bridges and connect to the xylem and phloem of a wide variety of host plants. Because of their unique lifestyle, research into processes like the formation of connections in between plant cells and plant immunity would benefit from <i>Cuscuta</i> as a model system. However, a method to study gene functions in a <i>Cuscuta</i> ...
    • Evolution of seasonal adaptations in voles - a physiological and genetic approach 

      Van Dalum, Mattis Jayme (Doctoral thesis; Doktorgradsavhandling, 2022-05-06)
      <p>This thesis addressed phenotypic and genetic variation in seasonal time keeping mechanisms of the tundra vole (<i>Microtus oeconomus</i>) and the common vole (<i>Microtus arvalis</i>). Voles (<i>Microtus</i>) are short-lived, non-hibernating and seasonally breeding rodents. The genus has rapidly evolved (< 2 million years) into one of the most speciose mammalian genera (Sitnikova et al. 2007; ...
    • Tangled up in prices going up and down: price determination in selected agri-food markets 

      Kidane, Dejene Gizaw (Doctoral thesis; Doktorgradsavhandling, 2022-05-02)
      <p>The dissertation includes four papers altogether. Three papers examine mechanisms for price transmission between markets. Among them, one deals with price transmission along the supply chain, and the other two deal with price transmission across spatially distinct markets. The fourth paper measures the effects of demand shifts on the market price equilibrium. <p>Paper 1 investigates price ...
    • POSITIONAL CONCERNS - How and why, and with what effect, are we positional when comparing with those around us? 

      Mageli, Ingvild (Doctoral thesis; Doktorgradsavhandling, 2022-05-12)
      We took an experimental approach to study what may contribute to such behavior, and what effect these choices have on individual wellbeing. We used three independent surveys to analyze this, all three measuring positional preferences in a broad spectrum of domains. If left uncorrected, there might be large unintended external effects from positional preferences, which is why this research is necessary. ...
    • Conceptualizing fishery systems: A mental models approach 

      Sam, Theodora (Doctoral thesis; Doktorgradsavhandling, 2022-04-22)
      Thinking of fisheries as a system is a relatively new approach in fisheries science and management. As part of my contribution to this perspective, this thesis uses mental models as a new approach to gain insights into how individuals conceptualize fisheries. Mental models are internal representations of the surrounding world (e.g., phenomena, processes, problems) and they are important because these ...
    • Land-Ocean Interactions in a Changing Arctic: Effects of terrestrial inputs on coastal food-web carbon source and contamination in Isfjorden, Svalbard 

      McGovern, Maeve (Doctoral thesis; Doktorgradsavhandling, 2022-04-29)
      Climate change driven increases in temperature are enhancing land-ocean connectivity in the coastal Arctic, with a range of implications for coastal food-webs and contaminant cycling. Terrestrial inputs are a direct source of carbon and legacy contaminants to coastal areas, but as a source of freshwater, nutrients and suspended inorganic sediments, they can also affect coastal food-webs and contaminant ...
    • Bioprospecting of marine microorganisms for the discovery of antibacterial compounds - Isolation, structure elucidation and bioactivity assessment of marine microbial natural products 

      Jenssen, Marte (Doctoral thesis; Doktorgradsavhandling, 2022-04-27)
      <p>Infectious diseases have been a problem for humans since the beginning of human existence. The “golden age” of antibiotics started at the end of the 1920s, with the discovery of penicillin by Sir Alexander Fleming. This was followed by the discovery of several life-saving antibiotics. The number of new marketed antibiotics has declined, and most pharmaceutical companies are no longer working in ...
    • Investigating the drivers of the Nordic Seas food-web dynamics using Chance and Necessity modelling 

      Sivel, Elliot (Doctoral thesis; Doktorgradsavhandling, 2022-04-22)
      Marine ecosystems are under pressures of human activities that have altered their dynamics and structure during the last five decades, but there can also vary due to internal dynamics or chance. Managers focus on human activities and often ignore the contribution of internal dynamics and chance to ecosystem dynamics in the decision-making process. In this thesis, I use food-web modelling based on ...
    • Consumers’ Value Perceptions of Seafood 

      Hoque, Mohammed Ziaul (Doctoral thesis; Doktorgradsavhandling, 2022-04-08)
      Consumers’ perception of seafood products plays a critical role in determining their consumption behaviour. As a great quantity of seafood is produced by aquaculture, specifically farmed fish, consumers’ perception of farmed fish is crucial. In recent years, consumers in developing and emerging countries have increased their concern about seafood safety. This thesis investigates consumers’ ...
    • Climate warming impact on the deep demersal fish community East of Greenland 

      Emblemsvåg, Margrete (Doctoral thesis; Doktorgradsavhandling, 2022-04-06)
      This thesis presents a study of the impact of climate warming on deep demersal fish communities East of Greenland, in a transition zone between Atlantic and Arctic waters. Climate change was expected to affect fish community composition and functional characterization via poleward distributional shifts and changes in abundance. To assess the climate driven effects on fish communities, I used long ...
    • Bioprospecting of Arctic marine microorganisms. Exploring microbial secondary metabolite production using the one strain-many compounds approach: isolation and characterization of secondary metabolites 

      Kristoffersen, Venke (Doctoral thesis; Doktorgradsavhandling, 2021-12-20)
      <p>Natural products have been used by humans since ancient times as benefactors for improved health. Prior to modern medicine and chemistry, these compounds remained hidden in the plants, animals and other organisms used to heal inflammation, wounds, headache and stomachache among other conditions. Since the start of modern drug discovery with isolation of morphine in 1805, numerous natural products ...
    • Bycatch reduction and alternative exploitation patterns in demersal trawl fisheries of the Baltic Sea and the North Sea 

      Santos, Juan (Doctoral thesis; Doktorgradsavhandling, 2021-12-17)
      <p>In the Baltic Sea and North Sea, the sustainability of bottom-trawl fisheries is threatened by many issues, such as the impact of climate change on exploited demersal stocks, long-term overfishing, and the European Landing Obligation for quoted species. This thesis identifies challenges to bycatch and harvesting patterns of targeted species in four relevant Baltic Sea and North Sea bottom-trawl ...
    • Antecedents of consumer evaluation and consumption of functional food 

      Nystrand, Bjørn Tore (Doctoral thesis; Doktorgradsavhandling, 2021-12-15)
      The overall aim of this dissertation is to improve the theoretical and empirical understanding of consumers’ behavioral tendencies toward functional food consumption. The main purpose is to provide a deeper understanding of antecedents that are relevant for explaining consumer evaluation of functional food and consumption behavior. Functional foods are food products that have been enriched to make ...
    • Effect of light quality on the biosynthesis of flavonoids and sugars in bilberry (Vaccinium myrtillus L.) 

      Samkumar, Amos (Doctoral thesis; Doktorgradsavhandling, 2021-12-09)
      Berries are abundant in bioactive compounds. Bilberry or European blueberry (<i>Vaccinium myrtillus</i> L.) is in particular gaining worldwide attention being one of the best natural sources of antioxidant rich phenolics that accumulate in both skin and flesh during fruit ripening. Alongside, the ubiquitous presence of anthocyanins and related flavonoids, it also contains other compounds such as ...
    • Microbial community structure associated to Arctic cold seeps 

      Carrier, Vincent (Doctoral thesis; Doktorgradsavhandling, 2021-11-29)
      Cold seeps are locations on the seafloor where CH<sub>4</sub> migrates from reservoirs below sediments towards the atmosphere, sustaining thereby a high microbial and macrofaunal biomass and a diversity contrasting from the surrounding seafloor. The oxidation of methane and sulphide are typically the main sources of primary productivity of these ecosystems and have therefore gained a particular ...
    • Economic incentives in outpatient care and patient demand for pharmaceuticals. A study of antibiotics and addictive drugs prescriptions 

      Zykova, Yana (Doctoral thesis; Doktorgradsavhandling, 2021-12-07)
      The questions asked in this thesis relate to the economic incentives and characteristics of the health care market, which may result in suboptimal drug prescription. We consider two types of pharmaceuticals, such as antibiotics and addictive drugs. These pharmaceuticals are interesting because their use/misuse is associated with costs both at the individual and societal levels. The decision about ...