Sökning: "trophic interactions"

Visar resultat 6 - 10 av 89 avhandlingar innehållade orden trophic interactions.

  1. 6. Zooplankton growth and trophic linkages : Implications for fish feeding conditions in the Baltic Sea

    Författare :Towe Holmborn; Elena Gorokhova; Sture Hansson; Ilppo Vuorinen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; AARS activity; biochemical markers; Clupea harengus; copepod physiology; food web interactions; non-indigenous species; RNA-based indices; Sprattus sprattus; stable isotopes; Marine ecology; Marin ekologi; Marine Ecology; marin ekologi;

    Sammanfattning : The aim of this Thesis was to improve our understanding and assessment of feeding conditions for zooplanktivorous fish in the Baltic Sea.We investigated (papers I, II) the usefulness of biochemical proxies for assessments of growth and metabolic rates in the dominant Baltic copepod Acartia bifilosa. LÄS MER

  3. 7. Trophic ecology of meiofauna : Response to sedimentation of phytoplankton blooms in the Baltic Sea

    Författare :Francisco J.A. Nascimento; Ragnar Elmgren; Richard Warwick; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Meiofauna; Cyanobacteria; competition; facilitation; ecosystems processes; Marine ecology; Marin ekologi; Marine Ecology; marin ekologi;

    Sammanfattning : Marine soft sediments are the second largest habitat on Earth. How animal communities in this habitat are structured is a central issue in marine ecology. Food is an important limiting factor for many benthic populations, and settling organic matter from phytoplankton blooms is of vital importance to them. LÄS MER

  4. 8. Interactions between gray-sided voles (Clethrionomys rufocanus) and vegetation in the Fennoscandian tundra

    Författare :Jonas Dahlgren; Lauri Oksanen; Johan Olofsson; John Terborgh; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gray-sided voles; tundra vegetation; trophic cascades; plant-herbivore interactions; bilberry; plant communities; herbivory; plant resistance; Terrestrial ecology; Terrestisk ekologi;

    Sammanfattning : I have, in this thesis, studied the interactions between gray-sided voles (Clethrionomys rufocanus) and tundra vegetation, on islands in, and mainland sites close to the lake Iešjávri, in northern Norway. As isolated islands are virtually free of predation, I have been able to compare plant-herbivore interactions in the presence and absence of predators. LÄS MER

  5. 9. Trophic complexity of zooplankton–cyanobacteria interactions in the Baltic Sea : Insights from molecular diet analysis

    Författare :Nisha H. Motwani; Elena Gorokhova; Jakob Walve; Catherine Legrand; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bloom-forming filamentous cyanobacteria; diazotrophs; picocyanobacteria; zooplankton; grazing; molecular diet analysis; stable isotopes; biochemical indices; Marine Ecology; marin ekologi;

    Sammanfattning : Blooms of nitrogen fixing cyanobacteria (NFC) occur in many freshwater and marine systems, including the Baltic Sea. By fixing dissolved nitrogen, they circumvent general summer nitrogen limitation, while also generating a supply of novel bioavailable nitrogen for non-diazotrophic primary producers and ultimately supporting secondary production. LÄS MER

  7. 10. Trophic, Indirect, and Evolutionary Interactions in a Plant–Herbivore–Parasitoid System

    Författare :Johan Stenberg; Lars Ericson; John Parker; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant resistance; coevolution; herbivory; Skeppsvik; food web; parasitism; maternal effect; natural selection; Filipendula ulmaria; Chrysomelidae; Terrestrial ecology; Terrestisk ekologi;

    Sammanfattning : The aim of this thesis project was to elucidate patterns and processes associated with the biotic interactions in a natural plant–herbivore–parasitoid food web characterized by spatial and temporal heterogeneity with regard to species composition. The system examined is based on island populations of the perennial herb Meadowsweet (Filipendula ulmaria, Rosaceae), located in the Skeppsvik Archipelago. LÄS MER