Sökning: "nitrogen limitation"

Visar resultat 1 - 5 av 62 avhandlingar innehållade orden nitrogen limitation.

  1. 1. Marine nitrogen fixation : Cyanobacterial nitrogen fixation and the fate of new nitrogen in the Baltic Sea

    Författare :Isabell Klawonn; Helle Ploug; Lasse Riemann; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biogeochemistry; nitrogen cycling; nitrogen fixation; cyanobacteria; Baltic Sea; Marine Ecology; marin ekologi;

    Sammanfattning : Biogeochemical processes in the marine biosphere are important in global element cycling and greatly influence the gas composition of the Earth’s atmosphere. The nitrogen cycle is a key component of marine biogeochemical cycles. LÄS MER

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

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

    Sammanfattning : .... LÄS MER

  4. 3. Nutrient Limitation of Bacterial Growth in Soil

    Författare :Fredrik Demoling; Biologiska institutionen; []
    Nyckelord :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

  5. 4. Nitrogen, parasites and plants : key interactions in boreal forest ecosystems

    Författare :Joachim Strengbom; Lars Ericson; Gaius R Shaver; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Critical loads; Deschampsia flexuosa; amino acids; mycorrhizal fungi; natural enemies; N deposition; N limitation; vegetational composition; Valdensia heterodoxa; Vaccinium myrtillus;

    Sammanfattning : In the work described in this thesis I studied how increases in nitrogen (N) inputs may affect plant community structure in boreal forest understorey vegetation. These phenomena were investigated in N fertilization experiments and along a national N deposition gradient. LÄS MER

  7. 5. The role of nutrients for stream ecosystem function in Arctic landscapes : drivers of productivity under environmental change

    Författare :Maria Myrstener; Ryan A. Sponseller; Reiner Giesler; Ann-Kristin Bergström; Tenna Riis; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nutrients; Stream; Arctic; Boreal; Primary productivity; Algae; Biofilm; Nutrient limitation; Nitrogen; Phosphorus;

    Sammanfattning : Arctic and sub-Arctic freshwaters are currently experiencing substantial ecosystem changes due to the effects of global warming. Global warming effects on these freshwaters include increasing water temperatures, altered hydrological patterns, shifts in riparian vegetation and changes in the export of nutrients and carbon from soils. LÄS MER