Sökning: "stoichiometry"

Visar resultat 6 - 10 av 131 avhandlingar innehållade ordet stoichiometry.

  1. 6. The impact of cormorant nesting colonies on plants and arthropods

    Författare :Gundula S. Kolb; Peter Hambäck; Lenn Jerling; Post David; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; seabirds; cormorants; islands; nitrogen; phosphorus; plants; arthropods; δ15N; Baltic Sea; ecological stoichiometry; species richness; species composition; numeric response; Biology; Biologi; Plant Ecology; växtekologi;

    Sammanfattning : Seabirds concentrate large amounts of marine nutrients on their nesting islands. This nutrient input can have large consequences for island food webs and community structure. The high nutrient load may also cause runoff into surrounding waters and affect marine communities. LÄS MER

  3. 7. The Invasion of the Zebra Mussel - Effects on Phytoplankton Community Structure and Ecosystem Function

    Författare :Rahmat Naddafi; Kurt Pettersson; Peter Eklöv; Willem Goedkoop; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Invasive species; Zebra mussel; Invasion success; Selective feeding; Non-lethal effects of predator; Seston stoichiometry; Delayed fluorescence excitation spectroscopy; Phytoplankton dynamics; Trait-mediated indirect interaction; Ecosystem function;

    Sammanfattning : Biological invasion has become a major threat to economy, ecology, global biodiversity and ecosystem function of aquatic ecosystems. The main aim of the thesis was to study the effects of the zebra mussel (Dreissena polymorpha), a versatile invasive species, on phytoplankton dynamics and ecosystem function of lakes. LÄS MER

  4. 8. Effects of inorganic nitrogen and organic carbon on pelagic food webs in boreal lakes

    Författare :Anne Deininger; Ann-Kristin Bergström; Jan Karlsson; Antonia Liess; Carolyn L. Faithfull; John A. Downing; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; autochthony; basal production; boreal; global change; dissolved organic carbon; food web efficiency; N deposition; phytoplankton; seston stoichiometry; whole lake enrichment; zooplankton; limnologi; Limnology;

    Sammanfattning : Anthropogenic activities are increasing inorganic nitrogen (N) loadings to lakes in the northern hemisphere. In many boreal lakes phytoplankton are N limited, wherefore enhanced N input may affect the productivity of pelagic food webs. LÄS MER

  5. 9. Organic carbon dynamics in the Baltic Sea : A modelling perspective

    Författare :Filippa Fransner; Jonas Nycander; Christoph Humborg; Andreas Oschlies; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbon cycle; organic carbon; primary production; remineralisation; terrestrial DOC; extracellular DOC; flexible stoichiometry; Redfield ratio; air-sea CO2 exchange; pCO2; coupled 3D physical-biogeochemical modelling; Gulf of Bothnia; Baltic Sea; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : Coastal seas constitute a link between land and the open ocean, and therefore play an important role in the global carbon cycle. Large amounts of carbon, of both terrestrial and marine origin, transit and are transformed in these waters, which belong to the more productive areas of the oceans. LÄS MER

  7. 10. Food Quality Effects on Zooplankton Growth and Energy Transfer in Pelagic Freshwater Food Webs

    Författare :Jonas Persson; Tobias Vrede; Peter Eklöv; Ellen van Donk; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; elemental stoichiometry; phosphorus; polyunsaturated fatty acids; EPA; oligotrophic lakes; empirical modelling; Daphnia; Cladocera; Copepoda; Ekologi;

    Sammanfattning : Poor food quality can have large negative effects on zooplankton growth and this can also affect food web interactions. The main aims of this thesis were to study the importance of different food quality aspects in Daphnia, to identify potentially important differences among zooplankton taxa, and to put food quality research into a natural context by identifying the importance of food quality and quantity in lakes of different nutrient content. LÄS MER