Sökning: "indirect effects"

Visar resultat 21 - 25 av 445 avhandlingar innehållade orden indirect effects.

  1. 21. 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

  3. 22. Direct and indirect effects of fish predation and excretion in aquatic food webs

    Författare :José Luiz Attayde; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

    Sammanfattning : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. LÄS MER

  4. 23. Effects of Testing and Enactment on Memory

    Författare :Veit Kubik; Lars-Göran Nilsson; Fredrik Jönsson; Jonas Olofsson; Monika Knopf; Mihály Racsmány; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; testing effect; test-potentiated learning; enactment effect; cued recall; forgetting; episodic memory; Psychology; psykologi;

    Sammanfattning : Learning occurs not only when we encode information but also when we test our memory for this information at a later time. In three empirical studies, I investigated the individual and combined effects of interleaved testing (via repeated rounds of study and test practice) and encoding (via motor enactment) during learning on later cued-recall performance for action phrases. LÄS MER

  5. 24. Analysis of fluoroalkyl sulfonamide (FASA) based copolymers : An indirect source of non-polymeric PFAS

    Författare :Felicia Fredriksson; Leo W. Y. Yeung; Anna Kärrman; Ulrika Eriksson; Robert Letcher; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PFAS; FASA-based copolymers; fluorine mass balance; EOF; sludge; TF; earthworm; exposure;

    Sammanfattning : Per- and polyfluoroalkyl substances (PFAS) are an extensive group of anthropogenic compounds and are of global concern due to their negative effects on the environment and humans. Most environmental research reports non-polymeric PFAS, leading to a scarce understanding of polymeric PFAS, despite their large share on the global market. LÄS MER

  7. 25. Theoretical Description of Electronic Transitions in Large Molecular Systems in the Optical and X-Ray Regions

    Författare :Nanna Holmgaard List; Jacob Kongsted; Hans Jørgen Aagaard Jensen; Roberto Cammi; Jeppe Olsen; Jens Oddershede; Denmark University of Southern Denmark Chemistry and Biology Department of Physics; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polarizable embedding; multiscale modeling; localized electronic transitions; response theory; QM MM; damped linear response; non-dipolar effects; light-matter interactions; multipole expansion; embedding potentials; local field effects; fluorescent proteins; computational chemistry; MCSCF; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

    Sammanfattning : The size and conformational complexity of proteins and other large systems represent major challenges for today's methods of quantum chemistry.This thesis is centered around the development of new computational tools to gain molecular-level insight into electronic transitions in such systems. LÄS MER