Sökning: "limitation"

Visar resultat 1 - 5 av 666 avhandlingar innehållade ordet limitation.

  1. 1. Beyond carbon-limitation : A re-evaluation of the ecological role of photorespiration and direct oxygen photoreduction in seagrasses

    Författare :Pimchanok Buapet; Mats Björk; Ilana Berman-Frank; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Carbon limitation; Chlorophyll fluorescence; Electron transport rate; Irradiance; Mehler reaction; Non-photochemical quenching; Photorespiration; Photosynthetic activity; Plant Physiology; växtfysiologi;

    Sammanfattning : Seagrasses living in shallow coastal waters are regularly subjected to changes in environmental conditions including the two essential factors for photosynthesis: dissolved inorganic carbon (DIC) and irradiance. This thesis focuses on the photosynthetic responses of seagrasses to carbon limitation induced by community metabolism and/or high light intensities. LÄS MER

  2. 2. Recruitment ecology and fungal interactions in mycoheterotrophic Ericaceae

    Författare :Veronika A. Johansson; Ove Eriksson; Andrew Taylor; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; 454 Pyrosequencing; Dispersal limitation; Dust seeds; Ectomycorrhiza; Ericaceae; Microsite limitation; Monotropa hypopitys; Mycoheterotroph; Pyroleae; Seed limitation; Stable isotopes; Subterranean seedling; Symbiotic germination; Tricholoma; Plant Ecology; växtekologi;

    Sammanfattning : There are generally two contrasting alternatives to what limits recruitment in plants, namely the availability of seeds (seed limitation) or the quality or quantity of suitable sites (microsite limitation). Dust seeds, the smallest existing seeds, lack or have minimal nutrient reserves. LÄS MER

  3. 3. Effects of temperature and terrestrial carbon on primary production in lake ecosystems

    Författare :Mohammed Hamdan; Jan Karlsson; Pär Byström; Erin R. Hotchkiss; Lars-Anders Hansson; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; lakes; primary production; benthic; pelagic; carbon dioxide limitation; light limitation; nutrient limitation; browning; warming; allochthonous carbon; grazing; trophic cascades;

    Sammanfattning : Climate warming is predicted to affect northern lake food webs in two ways: (1)directly via changes in water temperature and ice conditions, and (2) indirectlyvia changes in catchment characteristics and processes that influence input ofallochthonous coloured dissolved organic matter (cDOM) and nutrients. Input ofcDOM increases carbon dioxide (CO2) availability, causes brownification andreduced light conditions, and may increase nutrient availability especially forpelagic primary producers. LÄS MER

  4. 4. Nitrate assimilation in Pisum and Lemna : effects of nitrogen limitation

    Författare :Petter Oscarson; Stockholms universitet; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  5. 5. Nutrient Limitation of Bacterial Growth in Soil

    Författare :Fredrik Demoling; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ekologi; Ecology; Fertilization; Bacteria; Soil; Fungi; Thymidine or Leucine incorporation; Growth limitation; Phosphorus; Nitrogen; Carbon;

    Sammanfattning : Lack of carbon has been assumed to be the most common limiting factor for bacterial growth in soil, although there are reports of limitation by nitrogen and phosphorus. I have studied nutrient limitation of bacterial growth in soil using a novel technique, where thymidine or leucine incorporation is used to detect changes in growth rates after adding nutrients. LÄS MER