Sökning: "mountain birch"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden mountain birch.

  1. 1. The nitrogen economy of mountain birch : As related to environmental conditions and genotype

    Författare :Martin Weih; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Betula pubescens ssp. czerepanovii; growth; nitrogen; subarctic; temperature; ultraviolet radiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Responses of mountain birch growth to changed environmental conditions arestrongly affected by birch genotype, and nitrogen economy is a key factor influencingthe winter survival of first-year seedlings. These are some of the findings of a series ofstudies, in which growth, nitrogen economy and winter survival were analysed usingpot-grown seedlings of mountain birch (Betula pubescens ssp. LÄS MER

  3. 2. Biogeochemistry in Subarctic birch forests : Perspectives on insect herbivory

    Författare :Jeppe Ågård Kristensen; MERGE: ModElling the Regional and Global Earth system; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biogeochemistry; Aboveground-belowground interactions; Herbivory; Insects; Subarctic; Birch; soil microbes;

    Sammanfattning : Herbivory can influence ecosystem processes, partly through long-term changes of the plant community compositions, but also more rapidly through the herbivores’ digestive alteration of the organic matter that is cycled through the soil and back to the primary producers. In the Subarctic mountain birch (Betula pubescens ssp. LÄS MER

  4. 3. Spatial and temporal dynamics of subarctic birch forest carbon exchange

    Författare :Michal Heliasz; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mountain birch; eddy covariance; carbon budget; insect outbreak; forest expansion; temporal variability; spatial variability;

    Sammanfattning : High northern latitudes are of special importance for the global carbon budget as they store large amounts of organic matter in the soil and are expected to be the most strongly affected by climate change. Here we investigate carbon exchange in the subarctic mountain birch forest growing on the limit where tree growth is possible. LÄS MER

  5. 4. Structural Growth in Mountain Birch, Betula pubescens ssp. czerepanovii

    Författare :Christina Borg; Brita Svensson; Staffan Karlsson; Seppo Neuvonen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : In this thesis, I have studied long shoot performance in the monoecious, deciduous tree Betula pubescens ssp. czerepanovii. LÄS MER

  7. 5. Evapotranspiration and energy exchange of a mountain birch forest, Abisko, Sweden

    Författare :Magnus Ovhed; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER