Sökning: "biogeochemistry"

Visar resultat 31 - 35 av 51 avhandlingar innehållade ordet biogeochemistry.

  1. 31. The role of vegetation dynamics in the control of atmospheric CO2 content

    Författare :Stephen Sitch; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atmospheric CO2 content; climate change; plant functional types; terrestrial biosphere model; DGVM; vegetation dynamics; land use; land cover change; Plant ecology; Växtekologi;

    Sammanfattning : This thesis contains a description of the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM) and its application to infer the role of vegetation dynamics on atmospheric CO2 content at different time-scales. The model combines vegetation dynamics and biogeochemistry in a modular framework. LÄS MER

  3. 32. Recovery from Acidification - Policy Oriented Dynamic Modeling

    Författare :Liisa Fransson; Institutioner vid LTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kemiteknik och kemisk teknologi; Petrology; mineralogy; geochemistry; Petrologi; mineralogi; geokemi; Chemical technology and engineering; target loads; sea-salt episode; sulfate adsorption; SAFE; LRTAP; critical loads; integrated assessment;

    Sammanfattning : Dynamic biogeochemistry models are important tools for determining the time-scales of recovery from acidification. In the review process of the 1999 UNECE LRTAP Gothenburg protocol, results from dynamic models will probably be included when determining further reductions of acidifying emissions. LÄS MER

  4. 33. Environmental conditions governing the distributions of symbiotic and free-living diazotrophic cyanobacteria in two tropical open oceans

    Författare :Marcus Stenegren; Rachel Foster; Bethany Jenkins; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nitrogen fixation; Diazotroph; Cyanobacteria; Symbiosis; DDA; Richelia; Marine Ecology; marin ekologi;

    Sammanfattning : Di-nitrogen (N2) fixation plays a crucial role in oceanic carbon and nitrogen cycles and is important for marine biogeochemistry on regional and global scales. N2-fixing (diazotrophs) cyanobacteria are considered to contribute the most to marine nitrogen fixation, and thereby fuel the surrounding phytoplankton communities with bioavailable ammonia. LÄS MER

  5. 34. Atmospheric & Oceanic Applications of Eulerian and Lagrangian Transport Modelling

    Författare :Joakim Kjellsson; Kristofer Döös; Jonas Nycander; Joseph LaCasce; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Eulerian; Lagrangian; trajectory; climate; atmosphere; ocean; modelling; drifter; thermodynamic; climate change; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : This thesis presents several ways to understand transports of air and water masses in the atmosphere and ocean, and the transports of energy that they imply. It presents work using various kinds of observations as well as computer simulations of the atmosphere and oceans. LÄS MER

  7. 35. Mercury methylation in boreal peatlands: Influence of geochemistry and biology

    Författare :Baolin Wang; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Methylmercury (MeHg) is a neurotoxin mainly produced by microorganisms in suboxic and anoxic environments such as peatlands. Peatlands are an important source of MeHg in adjacent aquatic ecosystems, thus increasing the risk of human and wildlife exposure to this toxic compound. LÄS MER