Sökning: "aquatic consumers"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden aquatic consumers.

  1. 1. Climate change impacts on aquatic consumer communities

    Författare :Shuntaro Koizumi; Pär Byström; Ryan Sponseller; Jonathan Shurin; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Climate change; warming; browning; aquatic consumers; zooplankton; benthic insects; fish; ecosystem experiment; environmental science; miljövetenskap;

    Sammanfattning : Climate change represents a serious threat to aquatic ecosystems, with an increase in lake temperatures already observed that is expected to continue in the near future. Aside from the direct effects of warming, climate change is also partially responsible for the browning of lakes. LÄS MER

  2. 2. Psychotropic Pharmaceuticals in Aquatic Systems: An Ecological Perspective

    Författare :Melanie Hedgespeth; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ecotoxicology; aquatic; trophic level; pharmaceutical; SSRI; beta-blocker; sertraline; fluoxetine; propranolol; fish; daphnia; snail; predator; prey; behavior; life history; multiple stressor;

    Sammanfattning : Psychotropic pharmaceuticals have been shown to exert a variety of sublethal effects on non-target organisms, even at low concentrations found in the environment (ng/L to µg/L); hence, the aim of my research has been to determine the individual-level effects of psychotropic pharmaceuticals (the selective serotonin reuptake inhibitors sertraline and fluoxetine, and the β-blocker propranolol) on behavioral and life history traits in freshwater organisms. Further, this research was directed towards assessing the potential large-scale impacts of these effects on population growth and predator-prey interactions (with community-level implications) via the application of traditional, ecological concepts and models. LÄS MER

  3. 3. Impact of food quality on aquatic consumers : Behavioral and physiological adjustments

    Författare :Alfred Burian; Winder Monika; Kevin Flynn; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Marine Ecology; marin ekologi;

    Sammanfattning : Food quantity and quality together determine growth rates of consumers and the utilisation efficiencies of available resources in aquatic and terrestrial ecosystems. The effect of food quality on the performance of consumers is dependent on both, its direct influence on ingestion and assimilation rates, and on the behavioural and physiological adjustments of consumers to their food environment. LÄS MER

  4. 4. Characterisation of PFASs and Organofluorine in Freshwater Environments : Transfer from water to land via emergent aquatic insects

    Författare :Alina Koch; Thanh Wang; Micael Jonsson; Leo W. Y. Yeung; Anna Kärrman; Lutz Ahrens; Jonathan Martin; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PFASs; riparian zone; emergent aquatic insects; terrestrial consumers; stable isotopes; organofluorine mass balance; AFFF; point sources;

    Sammanfattning : Per- and polyfluoroalkyl substances (PFASs) are anthropogenic contaminants of emerging concern, because many are highly persistent to degradation and have been linked to adverse effects in humans as well as their ubiquitous spread in aquatic environments. This thesis investigated distribution of PFASs and organofluorine in freshwater environments impacted by PFAS point sources. LÄS MER

  5. 5. Consumption patterns and excretion in aquatic food websenrichment

    Författare :Anders Persson; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; trophic interactions; translocation; biomanipulation; enrichment; phosphorus; model; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Sammanfattning : This thesis links biogeochemical cycling to classical ecology. Predictions derived from food chain theory, based on Lotka-Volterra type of interactions, were tested in aquatic environments with the main hypothesis that consumers affect lower levels of organization by both predation and excretion of limiting nutrients. LÄS MER