Search for dissertations about: "aquatic macrophytes"

Showing result 11 - 15 of 24 swedish dissertations containing the words aquatic macrophytes.

  2. 11. Regulation and role of epiphytic nitrification and denitrification in macrophyte-dominated systems

    Author : Peder Eriksson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; submerged; emergent; epiphyton; bacteria; nitrate; wetland; nitrogen; littoral; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Abstract : This thesis examines mechanisms regulating bacterial nitrification and denitrification in attached microbial communities on surfaces of aquatic macrophytes. It also evaluates the role of epiphytic nitrification and denitrification for the nitrogen turnover in macrophyte-dominated nutrient-rich freshwaters. READ MORE

  4. 12. The effects of crayfish on interactions in freshwater benthic communities

    Author : Per Nyström; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; exotic species; trophic cascades; omnivory; crayfish; Trophic interactions; freshwater; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Abstract : This thesis examines how freshwater crayfish affect community interactions in benthic food webs. I have mainly studied the influence of the introduced signal crayfish (Pacifastacus leniusculus) on littoral communities, but also the influence of the native noble crayfish (Astacus astacus). READ MORE

  5. 13. Uptake and toxicity of brominated flame retardants and pesticides : Studies on littoral organisms and model communities

    Author : Kerstin Gustafsson; Nils Kautsky; Kirsten Christoffersen; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; aquatic ecotoxicology; ecological interactions; indirect effects; model community studies; toxicity; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Abstract : In this thesis, brackish and freshwater littoral model communities (microcosms) of varying size and complexity were used to study the effects of brominated flame retardants (BFRs) and pesticides. The brackish water microcosms consisted of natural water, sediment and associated organisms, while the larger freshwater microcosms also contained submersed macrophytes (Elodea canadensis). READ MORE

  6. 14. 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

  7. 15. Population biology of the clonal plant Ranunculus lingua

    Author : Mats E. Johansson; Christer Nilsson; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; clonal fragmentation; emergent macrophytes; fungal pathogens; hydrochoiy; invertebrate grazing; marginal population; Peronospora gigantea Prasocuris phellandrt regional abundance; rhizome production; size-number trade-off; vegetative reproduction; water-level fluctuation;

    Abstract : The scope of this thesis was to identify, describe and quantify important life-history traits for the pseudoannual aquatic plant Ranunculus lingua in different ecological settings, by comparing populations from geographically marginal vs. central habitats. READ MORE