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Visar resultat 16 - 20 av 127 uppsatser som matchar ovanstående sökkriterier.

  1. 16. Associations between body size polymorphism in Arctic charr and benthic invertebrate communities – clues to mechanisms for population differentiation?

    Master-uppsats, SLU/Dept. of Wildlife, Fish and Environmental Studies

    Författare :Andreas Sund; [2022]
    Nyckelord :arctic charr; benthic invertebrates; polymorphism;

    Sammanfattning : Many fish populations in the north have divided into coexisting ecotypes that differ in body size. While such polymorphic fish populations have been studied for many years, the understanding of how different types of selection contribute to the formation of dwarf- and giant ecotypes remains limited. LÄS MER

  3. 17. Aquaculture and its effect on the wild fish resource in a Swedish lake : An evaluation of changes in fat content, protein content and trophic niche

    Master-uppsats, SLU/Dept. of Wildlife, Fish and Environmental Studies

    Författare :Emmy Nyberg; [2022]
    Nyckelord :Aquaculture; wild fish; fat content; protein content; stable isotopes;

    Sammanfattning : Fish is nutritious and important as a food source for many people. It contains high levels of protein, important omega-3 fatty acids as well as micronutrients. For a sustainable fish consumption, aquaculture is needed but it can affect nearby ecosystems in many ways. LÄS MER

  4. 18. Acoustic Doppler Current Profiling for streamflow measurements in subarctic climate

    Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

    Författare :Linus Nyström; [2022]
    Nyckelord :;

    Sammanfattning : The ADCP (Acoustic Doppler Current Profiling) technology has been widely available and acknowledged as an instrument used for different types of flow measurement since 1990s, from small scale river measurements to larger ocean current mappings. This study was conducted by the author in cooperation with SWECO with the focus on smaller scale measurements especially on small natural watercourses in a sub-arctic climate with the purpose to examine if the ADCP technology can be used as a complement to the more classic methods for this type of flow measurements Current meter and Conductivity flow measurements. LÄS MER

  5. 19. Mikroplast i vattenavsatta sediment

    Kandidat-uppsats, Lunds universitet/Geologiska institutionen

    Författare :Björn Lycke; [2022]
    Nyckelord :Andong salt marsh; microplastics; MPs; trends; United Kingdom; Arctic; Tisza; Thames; Elbe; India; primary microplastics; secondary microplastics; PAH; polychlorinated biphenyls; toxic; poison; Earth and Environmental Sciences;

    Sammanfattning : Microplastics (MPs) are a major pollution concern since the start of the mass produc-tion of plastics in the 1950s. MPs form A) when plastics are produced intentionally to be part of beauty products and B) when plastics are broken down into smaller particles by sunlight, wind, and rain. LÄS MER

  7. 20. GIS, tracer test and water balance based hydrological analysis in Tarfala, Northern Sweden

    Kandidat-uppsats, Stockholms universitet/Institutionen för naturgeografi

    Författare :Elias Koivisto; [2022]
    Nyckelord :Tarfala; DEM; Tracer test; Water balance; the Arctic; Climate change; Permafrost; Glacier;

    Sammanfattning : Current climate change poses a threat to the Arctic due to increasing temperatures, which cause the permafrost and glaciers to melt and thaw. This thesis focused on analyzing water balances in Tarfala catchment between 2000 and 2020 and using GIS as a support for tracer test results measured in Tarfala in 2021. LÄS MER