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Visar resultat 1 - 5 av 39 avhandlingar som matchar ovanstående sökkriterier.

1. 1. The role of benthic macrofauna in nitrogen cycling in eutrophic lake sediment

   Författare :Jonas Martin Svensson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; nitrogen retention; nitrous oxide; oligochaetes; chironomids; mineralisation; nitrification; denitrification; eutrophic; sediment; lake; Macrofauna; nitrogen cycling; fish reduction.; Ecology; Ekologi;

   Sammanfattning : This thesis concerns the role of sediment-living macrobenthos in the cycling of nitrogen species and nitrogen transformation in eutrophic freshwater sediments. In my thesis I have, employing 15N-isotope techniques in laboratory experiments, shown the importance of infaunal chironomid larvae and oligochaetes on denitrification in eutrophic lake sediments. LÄS MER

3. 2. Waterfowl herbivory on submerged macrophytes in eutrophic lakes

   Författare :Håkan Sandsten; Biologiska institutionen; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

4. 3. The Niches of Bacterial Populations in Productive Waters : Examples from Coastal Waters and Four Eutrophic Lakes

   Författare :Alexander Eiler; Stefan Bertilsson; Lars J. Tranvik; Janet Jansson; Katherine McMahon; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; diversity; 16S rRNA; phytoplankton; bloom; pathogen; carbon cycle; Ekologi;

   Sammanfattning : Recent research in microbial ecology has focused on how aquatic bacterial communities are assembled. Only a few of these studies follow a “Gleasonian” approach where the roles of single bacterial populations are in focus. LÄS MER

5. 4. Deciduous forest vegetation in Boreo-nemoral Scandinavia

   Författare :Martin Diekmann; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Forest vegetation; Vegetation ecology; Oligotrophic oak forests; Mesotrophic mixed deciduous forests; Eutrophic elm-ash forests; Eutrophic alder-ash forests; Ekologi; Skogar;

   Sammanfattning : .... LÄS MER

7. 5. Submerged macrophytes in shallow eutrophic lakes - regulating factors and ecosystem effects

   Författare :John A Strand; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; plasticity; seed banks; periphyton; grazing; alternative stable state; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : In this thesis I have studied factors that regulate submerged macrophyte abundance, morphology and distribution in shallow eutrophic lakes, and how submerged macrophytes may affect the ecosystem. Light attenuation through the water column (turbidity and water depth) is probably not the most important factor regulating the distribution of submerged vegetation in macrophyte dominated shallow eutrophic lakes, e. LÄS MER