Search for dissertations about: "sjöar"

Showing result 11 - 15 of 89 swedish dissertations containing the word sjöar.

  2. 11. CO2 Emissions from Northern Lakes : Insights on regulation and spatiotemporal variability across contrasting lakes in Sweden

    Author : David Rudberg; David Bastviken; Paul Hanson; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lake; CO2 flux; Spatiotemporal variability; Empirical models; Sjö; Koldioxid-flöde; Rumsliga och tidsmässiga variationer; Empiriska modeller;

    Abstract : Lakes cover only ~2 % of the global land area, but their connections to the surrounding catchment make them important for the global carbon cycle. A considerable amount of the carbon input to lakes is emitted to the atmosphere as carbon dioxide (CO2) through diffusive flux. READ MORE

  4. 12. The different roles of crayfish in benthic food webs

    Author : Patrik Stenroth; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Marinbiologi; limnologi; aquatic ecology; marine biology; food chain length; stable isotopes; environmental gradients; diet; crayfish; akvatisk ekologi; limnology; Hydrobiology;

    Abstract : I show that crayfish consume detritus, algae, macrophytes, and an array of invertebrates. Crayfish were found to reduce invertebrate densities. However, prey mobility seemed to be a key factor regulating the strength of interactions between crayfish and prey. READ MORE

  5. 13. Role of phagotrophy in freshwater phytoplankton

    Author : Carina Pålsson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; aquatic ecology; marine biology; limnology; mixotrophy; phagotrophy; phytoplankton; oligotrophic; clear-water lakes; grazing; competition; nutrient enrichment; autotrophy; heterotrophy; bacterial ingestion; Hydrobiology; Marinbiologi; akvatisk ekologi; limnologi;

    Abstract : Some phytoplankton have the ability to combine phototrophy and heterotrophy within the same individual, which is called mixotrophy. In this thesis, I adress mixotrophy and competitive interactions of mixotrophs and obligate auto- or heterotrophs in relation to the availability of nutrients, light and prey. READ MORE

  6. 14. Allochthonous and autochthonous carbon sources of lake bacterioplankton

    Author : Emma Kritzberg; Enhet akvatisk ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Marinbiologi; limnologi; akvatisk ekologi; aquatic ecology; marine biology; Hydrobiology; bacterial community composition; bacterial growth efficiency; bacterioplankton; carbon subsidy; dissolved organic carbon; limnology;

    Abstract : Organic substrates for pelagic bacteria are derived from dissolved organic carbon (DOC) in the water column that originates either from primary production from within the lake itself (autochthonous), or import of organic matter from the terrestrial watershed (allochthonous production). This thesis addresses the utilization of allochthonous versus autochthonous carbon (C) sources by lake bacterioplankton. READ MORE

  7. 15. Waterfowl herbivory on submerged macrophytes in eutrophic lakes

    Author : Håkan Sandsten; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; limnology; Marinbiologi; limnologi; Hydrobiology; Växtekologi; Plant ecology; akvatisk ekologi; Djurekologi; Animal ecology; Anas; Fulica atra; Cygnus; alternative stable states; water depth; distribution; plant species composition; hydrophytes; propagule size; Herbivory; tuber; Potamogeton; marine biology; aquatic ecology;

    Abstract : Submerged macrophytes are thought to stabilize clear-water states of shallow lakes. The aim of this thesis was to elucidate how waterfowl herbivory can affect abundance, distribution and species composition of submerged macrophytes in eutrophic lakes. READ MORE