Search for dissertations about: "trophic level"

Showing result 1 - 5 of 56 swedish dissertations containing the words trophic level.

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

    University dissertation from Department of Biology, Lund University

    Author : Melanie Hedgespeth; Lund University.; Lunds universitet.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ecotoxicology; aquatic; trophic level; pharmaceutical; SSRI; beta-blocker; sertraline; fluoxetine; propranolol; fish; daphnia; snail; predator; prey; behavior; life history; multiple stressor;

    Abstract : 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. READ MORE

  2. 2. Omnivore population dynamics and trophic behavior

    University dissertation from Department of Biology, Lund University

    Author : Anna-Sara Liman; Sveriges lantbruksuniversitet.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Plant traits can mediate the interactions between plant feeding trophic omnivores and their herbivore prey via density effects and by altering the omnivore’s trophic behavior (plant vs. prey feeding). READ MORE

  3. 3. Perspectives from a human-centred archaeology : Iron Age people and society on Öland

    University dissertation from Lund University

    Author : Helene Wilhelmson; Lund University.; Lunds universitet.; [2017-03-15]
    Keywords : HUMANIORA; HUMANITIES; Osteology; bioarchaeology; Iron Age; Scandinavia; 3D; digital; Image Based Modeling; GIS; isotopes; Oxygen; Strontium; Carbon; Nitrogen; trophic level effect; fractionation; chronology; network; Virtual Taphonomy; human-centred archaeology; mortographies; dietary shift; integration; immigration; diet; migration; violence; burial; Viking Age; Öland; island;

    Abstract : The objective of this study was to develop, test and evaluate a specifically defined interdisciplinary approach—the human-centred approach—as applied to a case study, Iron Age Öland. Four themes were selected to highlight different aspects of particular interest in Öland: taphonomy, diet, migration, and social organization. READ MORE

  4. 4. Food Web Ecology -- individual life-histories and ecological processes shape complex communities

    University dissertation from Department of Biology, Lund University

    Author : Martin Hartvig; Lund University.; Lunds universitet.; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; food web; community ecology; community assembly; size-structure; life-history omnivory; ontogeny; trophic interactions; trait based model; topology; emergent organisation; size-spectrum;

    Abstract : This thesis sets out a food web framework for size-structured populations. The framework enables an ecological approach to food web modelling as the individual life-history from birth, through maturation, and ultimately death is explicitly resolved with the use of bioenergetics based on individual body size. READ MORE

  5. 5. Food web dynamics in open and closed systems

    University dissertation from Department of Biology, Lund University

    Author : Johan Lövgren; Umeå universitet.; [2004]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; allochtonous input; cross habitat foraging; donor control; heterogeneity within trophic level; compensation; food web; littoral; Ekologi; NATURAL SCIENCES Biology Terrestrial; freshwater and marine ecology; NATURVETENSKAP Biologi Terrestisk; limnisk och marin ekologi;

    Abstract : This thesis is a summary of enclosure and microcosm experiments that aimed to study the impact of allochtonous subsidies on food web dynamics in a heterogeneous food web. In the enclosure studies, a three trophic level littoral food web was used. READ MORE