Sökning: "Carbon fluxes"

Visar resultat 11 - 15 av 141 avhandlingar innehållade orden Carbon fluxes.

  1. 11. Cryogenic soil processes in a changing climate

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Marina Becher; Umeå universitet.; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Non-sorted circle; Carbon storage; Soil motion; Terrestrial photogrammetry; Cryoturbation; Carbon fluxes; naturgeografi; Physical Geography;

    Sammanfattning : A considerable part of the global pool of terrestrial carbon is stored in high latitude soils. In these soils, repeated cycles of freezing and thawing creates soil motion (cryoturbation) that in combination with other cryogenic disturbance processes may play a profound role in controlling the carbon balance of the arctic soil. LÄS MER

  2. 12. Land-atmosphere interaction of a subarctic palsa mire

    Detta är en avhandling från GeoBiosphere Science Centre, Department of Physical Geography and Ecosystems Analysis, Lund University, Sölvegatan 12, 223 62, Lund, Sweden

    Författare :Marcin Jackowicz-Korczynski; Lund University.; Lunds universitet.; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; eddy covariance; chamber; methnaol; isoprene; nonmethane hydrocarbons; methane; carbon dioxide; carbon; mire; permafrost; subarctic; palsa; greenhouse gas;

    Sammanfattning : The main objective of this thesis was to quantitatively estimate the gaseous exchange of carbon dioxide (CO2) and methane (CH4) between a subarctic wetland ecosystem and the atmosphere. Additionally some initial estimates of the carbon input to the atmosphere of nonmethane hydrocarbons (NMHCs) were also obtained by combining different techniques in a joint setting. LÄS MER

  3. 13. Impact of root and mycorrhizal exudation on soil carbon fluxes : influence of elevated CO2 and metals

    Detta är en avhandling från Örebro : Örebro universitet

    Författare :Emma M. Johansson; Örebro universitet.; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; amino acids; 13C; carbon cycle; ectomycorrhiza; elevated CO2; exudation; DOC; LMWOA; metal stress; monosaccharides; oxalate; Pinus sylvestris; saprotrophic fungi; soil respiration; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES Chemistry Environmental chemistry; NATURVETENSKAP Kemi Miljökemi; Enviromental Science; Miljövetenskap;

    Sammanfattning : The thesis concerns the behavior of root and ectomycorrhizal (ECM) exudates. In particular, the dynamics of soluble low molecular weight (LMW) organic compounds such as organic acids (LMWOAs), amino acids, monosaccharides, and dissolved organic carbon (DOC) have been studied. LÄS MER

  4. 14. Fluxes of Sensible and Latent Heat and Carbon Dioxide in the Marine Atmospheric Boundary Layer

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Erik Sahlée; Uppsala universitet.; [2007]
    Nyckelord :Meteorology; Sensible heat flux; Latent heat flux; Carbon dioxide; Turbulent exchange; Global heat fluxes; Marine boundary layer; Air-sea interaction; Meteorologi;

    Sammanfattning : Oceans cover about 70% of the earth’s surface. They are the largest source of the atmospheric water vapour and act as enormous heat reservoirs. Thus in order to predict the future weather and climate it is of great importance to understand the processes governing the exchange of water vapour and heat between the ocean and atmosphere. LÄS MER

  5. 15. Plant-soil-herbivore interactions in a high Arctic wetland - Feedbacks to the carbon cycle

    Detta är en avhandling från Department of Physical Geography and Ecosystem Science, Lund University

    Författare :Julie Maria Falk; Lund University.; Lunds universitet.; Lund University.; Lunds universitet.; [2014]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic wetlands; carbon balance; herbivory; increased grazing pressure; methane fluxes; muskox exclusion; substrate avalibility; vegetation composition and density;

    Sammanfattning : Arctic ecosystems hold massive amounts of the global carbon in their soils and are of great importance for the global terrestrial exchange of greenhouse gases to the atmosphere. The arctic region has in general been acting as a C sink for the past 10000 years, however with climate change the C balance in some areas is shifting towards becoming a C source. LÄS MER