Sökning: "indirect effects"

Visar resultat 1 - 5 av 392 avhandlingar innehållade orden indirect effects.

  1. 1. Indirect effects of river regulation : consequences for landbirds of reduced numbers of aquatic insects

    Författare :Darius Strasevicius; Björn Malmqvist; Tapio Eeva; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Boreal region; Simuliidae; Leucocytozoon; pied flycatcher; aquatic insects; breeding success; blood parasites; bird communities; river regulation; impoundment; Biology; Biologi;

    Sammanfattning : Abstrakt: Jag har undersökt hur älvreglering påverkar mängden knott (Tvåvingar: Simuliidae) längs flera norrlandsälvar och vilka konsekvenser denna påverkan får för den landlevande fågelfaunan. Studien visar att utbyggnad av älvar har en negativ effekt på mängden knott. LÄS MER

  2. 2. Ontogenetic bottlenecks : effects on intraguild predation systems and ecosystem efficiency

    Författare :Birte Reichstein; Lennart Persson; André M. De Roos; Priyanga Amarasekare; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; mixed interactions; cannibalism; life-history omnivory; ontogenetic niche shift; biomass overcompensation; biomass production; ontogenetic asymmetry; indirect effects; biology; biologi; zooekologi; Animal Ecology;

    Sammanfattning : Size-dependent differences between individuals in size-structured organisms have fundamental effect on population and community dynamics. Intraguild predation (IGP) is one specifically interesting constellation that often arises when two size-structured populations interact. LÄS MER

  3. 3. Non-target Effects of Genetically Modified Trees

    Författare :Patrik Blomberg; Anders Wennström; Jan Stenlid; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Genetically modified; GM trees; secondary metabolism; phytochemistry; Populus; transgenic; non-target effects; natural enemies; plant-pathogen herbivore interaction; environmental effects; parasitic fungi; herbivorous insect; Terrestrial ecology; Terrestisk ekologi;

    Sammanfattning : To date, few studies have focused on the effects of genetically modified trees (GM trees) on the environment. One concern with GM trees is that they may have unanticipated effects on non-target organisms, i.e. effects on organisms that are not direct targets of the genetically modified trait. LÄS MER

  4. 4. Understanding Weather effects on, in, and from large Herbivore Population Dynamics

    Författare :Lena Månsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; monitoring; management; data collection; Ecology; Ekologi; indirect effects; vegetation; modeling; time series analysis; precipitation; weather; population dynamics; Large herbivores;

    Sammanfattning : Large herbivores are monitored for various reasons in many areas around the world. Data from such monitoring can be of varying degree of detail and extent. Several studies have shown that we need extensive amounts of data with a high degree of detail to be able to understand anything from it. LÄS MER

  5. 5. Role of ecological processes in determining effects of contaminants in aquatic ecosystems

    Författare :Anna-Lea Golz; Clare Bradshaw; Karen Kidd; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; ecosystem approach; ionizing radiation; HBCDD; microcosm; species interactions; indirect effects; Marine Ecotoxicology; marin ekotoxikologi;

    Sammanfattning : Aquatic ecosystems cover approximately 70% of the Earth’s surface and support a wide range of ecosystem services. Despite their importance, aquatic ecosystems are increasingly exposed to anthropogenic stressors, such as contaminants and climate change impacts. LÄS MER