Search for dissertations about: "daphnia"

Showing result 1 - 5 of 35 swedish dissertations containing the word daphnia.

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

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Jonas Persson; Uppsala universitet.; [2007]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; elemental stoichiometry; phosphorus; polyunsaturated fatty acids; EPA; oligotrophic lakes; empirical modelling; Daphnia; Cladocera; Copepoda; Ekologi;

    Abstract : 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. READ MORE

  2. 2. Effects of warming and nutrient enrichment on feeding behavior, population stability and persistence of consumers and their resources

    University dissertation from Umeå : Umeå University

    Author : Wojciech Uszko; Umeå universitet.; [2016]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; consumer-resource; Daphnia; functional response; nutrient enrichment; parameter estimation; persistence; plankton; predator-prey; stability; temperature; type II; type III; warming;

    Abstract : Consumer-resource interactions are the basic building blocks of every food web. In spite of being a central research theme of longstanding interest in ecology, the mechanisms governing the stability and persistence of consumer-resource interactions are still not entirely understood. READ MORE

  3. 3. Daphnids adaptive strategies to UV radiation

    University dissertation from Lund University, Faculty of Engineering

    Author : Carla Eloisa Fernández; Lunds universitet.; Lund University.; [2018-04]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Cladocera; Zooplankton; Andean lakes; Daphnia; Ultraviolet radiation; Migration strategy; Photo-protection;

    Abstract : This thesis focuses on the adaptive strategies of daphnids that allows them to maintain stable populations while deal with UV radiation, highlighting the differences in the responses that populations with different evolutionary histories may have.Although exposition to lethal doses in nature is unlikely, sub-lethal UV-B radiation doses may have strong impacts on zooplankton. READ MORE

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

    University dissertation from Department of Biology, Lund University

    Author : Melanie Hedgespeth; Lunds universitet.; Lund University.; [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 : Popular Abstract in English Psychotropic pharmaceuticals include various groups of chemicals that have been designed to affect neurochemistry in human consumers resulting in changes in cognition, mood, and/or behavior; many target specific receptors and subsequently alter neurotransmitter levels in the central nervous system. The use of pharmaceuticals by consumers results in the release of these active substances and their breakdown products into the environment, the main source of which is through domestic wastewater treatment plants connected to households. READ MORE

  5. 5. The role of terrestrial and phytoplankton-derived organic matter in planktonic food webs

    University dissertation from Umeå : Umeå universitet

    Author : Anja Wenzel; Umeå universitet.; [2012]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Daphnia; phytoplankton; heterotrophic bacteria; terrestrial particulate organic material; food quality; food quantity; fatty acids; oligotrophic; Light:Nutrient-Hypothesis; limnologi; Limnology;

    Abstract : Lakes are important global ecosystems and many of them are nutrient-poor (unproductive). Especially in northern boreal latitudes, lakes may be heavily subsidized by terrestrial organic material (t-OM) from peat layers in the catchment. READ MORE