Sökning: "nitrogen content"

Visar resultat 1 - 5 av 231 avhandlingar innehållade orden nitrogen content.

  1. 1. Cyanobacterial Nitrogen Fixation in the Baltic Sea : With focus on Aphanizomenon sp

    Författare :Jennie B. Svedén; Jakob Walve; Helle Ploug; Angela Wulff; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cyanobacteria; Baltic Sea; nitrogen fixation; Aphanizomenon sp.; dissolved nitrogen; particulate nitrogen; sedimentation; Marine Ecology; marin ekologi;

    Sammanfattning : Cyanobacteria are widely distributed in marine, freshwater and terrestrial habitats. Some cyanobacterial genera can convert di-nitrogen gas (N2) to bioavailable ammonium, i.e. perform nitrogen (N) fixation, and are therefore of profound significance for N cycling. LÄS MER

  3. 2. 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

  4. 3. Microbial mobilization and immobilization of soil nitrogen

    Författare :Per Bengtson; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; growth rate; microbial activity; respiration; assimilation; immobilization; Nitrogen; mineralization;

    Sammanfattning : Microorganisms in forest ecosystems normally recycle nitrogen (N), such that gaseous losses and leaching are limited. Mobilization of organic N, including microbial N, and immobilization of inorganic N, especially NH4+, are the quantitatively most important N transformation processes. Various factors influence their rates, e.g. LÄS MER

  5. 4. Extraction of logging residues for bioenergy : effects of operational methods on fuel quality and biomass losses in the forest

    Författare :Bengt Nilsson; Johan Bergh; Gudmund Vollbrecht; Rolf Björheden; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Forest fuel; Storage; Fraction composition; Needles; Defoliation; Moisture content; Nutrients; Nitrogen; Norway spruce; Picea abies; Skogsbränsle; Lagring; Fraktionsfördelning; Barr; Avbarrning; Fukthalt; Näringsämnen; Kväve; Gran; Picea abies; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Wood products play a key role in the transformation to a more sustainable society based on renewable bio-based resources, together with the positive effects on climate mitigation by replacing fossil fuels. However, to increase the use of forest fuel in practice it is important to understand the effects of handling and storage on its quality and removal of nutrients from the forest. LÄS MER

  7. 5. Carbon and nitrogen in steel : determination of content and distribution by electron probe microanalysis (EPMA)

    Författare :Gunilla Runnsjö; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER