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Showing result 1 - 5 of 66 swedish dissertations matching the above criteria.

2. 1. Climate change effects on marine species across trophic levels

   Author : Nan Hu; Enhet akvatisk ekologi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; trophic levels; predation; gastropods; mussels; ocean acidification; ocean warming; interactive effects; interaction types; meta-analysis;

   Abstract : Climate change and anthropogenic activities are producing a range of new selection pressures, both abiotic and biotic, on marine organisms. While there are numerous studies that have investigated the response of individual marine organisms to climate change, few studies have focused on differences in organismal responses across trophic levels. READ MORE

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

   Author : Melanie Hedgespeth; Enhet akvatisk ekologi; []
   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

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

   Author : Helene Wilhelmson; begravning och social identitet Gravarkeologiska forskargruppen – Död; []
   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

6. 4. Food web dynamics in open and closed systems

   Author : Johan Lövgren; Lennart Persson; Jonathan Chase; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; allochtonous input; cross habitat foraging; donor control; heterogeneity within trophic level; compensation; food web; littoral; Ekologi; Terrestrial; freshwater and marine ecology; 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

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

   Author : Martin Hartvig; Evolutionär ekologi; []
   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