Sökning: "nitrogen accumulation"

Visar resultat 6 - 10 av 60 avhandlingar innehållade orden nitrogen accumulation.

  1. 6. On the ecophysiology of Baltic cyanobacteria focusing on bottom-up factors

    Detta är en avhandling från Göteborg : University of Gothenburg

    Författare :Malin Mohlin; Göteborgs universitet.; Gothenburg University.; [2010]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Allelopathy; Aphanizomenon sp.; Baltic Sea; Cyanobacteria; Diazotrophic; Multi-factorial; Nitrogen; Nodularin; photosynthetic active radiation; Phosphorus; ultraviolet radiation; UV-A; UV-B;

    Sammanfattning : Cyanobacterial blooms in the Baltic Sea are dominated by diazotrophic cyanobacteria, i.e. Aphanizomenon sp. and Nodularia spumigena. LÄS MER

  2. 7. Silicon cycling in the Baltic Sea Trends and budget of dissolved silica

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Liana Papush; Linköpings universitet.; Linköpings universitet.; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dissolved silica; trends; nutrient; nutrient ratios; diatoms; Redfield; limitation; eutrophication; riverine load; budget; fluxes; accumulation; retention; optimisation; Baltic Sea; Löst kisel; trender; näringsämne; näringsämnens kvoter; kiselalger; Redfield; tillväxtbegränsning; övergödning; flodtillförsel; budget; flöden; ackumulering; retention; optimering; Östersjön; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : The dissolved silicon (DSi) has a crucial role for growth of a large group of primary producers – diatoms and, hence, impact on functioning of the aquatic food web. This thesis contributes to an increased understanding of the modifications of the DSi cycling in the Baltic Sea. LÄS MER

  3. 8. Free-Vehicle Benthic Lander Technology for the Study of Biogeochemical Processes in Marine Sediments

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Anders Tengberg; Göteborgs universitet.; Gothenburg University.; [1997]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; marine sediments; benthic fluxes; incubations; chambers; in-situ; benthic landers; autonomous vehicles; lander technology; hydrodynamics; calibration; experimental design; Partial Least Squares PLS ; sensors; fugacity; oxygen; carbon; nitrogen; phosphorus; silica; dissolved organic carbon DOC ; total carbonate; recycling; burial;

    Sammanfattning : Various sediment sampling and incubation techniques were used to characterize benthic biogeochemical processes important for an improved understanding of the oceanic carbon cycle. Recent flux data from the Arctic Siberian shelf are revealing differences (often by a factor of ten) between areas affected by the big Russian river outlets (high fluxes) and areas with low influence from land (low fluxes). LÄS MER

  4. 9. Holocene carbon and nitrogen accumulation rates and contemporary carbon export in discharge

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Anna Larsson; Sveriges lantbruksuniversitet.; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The contemporary role of mires in land-atmosphere exchange of carbon dioxide (CO₂) is the subject of intense scientific debate. Investigating patterns and mechanisms of variations in past carbon (C) accumulation rates as well as contemporary C fluxes of peatlands facilitates predictions of future mire C sink strength under a changing climate. LÄS MER

  5. 10. Traditional lowland rice agriculture in Sri Lanka : Nitrogen cycling and options for biofertilizers

    Detta är en avhandling från Linköping : Linköpings universitet

    Författare :Ola Palm; Linköpings universitet.; Linköpings universitet.; [1988]
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

    Sammanfattning : The aim of this thesis has been: to study the dynamics of soil organic-matter, with regard to nitrogen in a traditional lowland-rice agricultural system; to consider options for and nitrogen cycling of biofertilizers, especially the green-manure legume Sesbania sesban; to discuss fertilizer sources and management constraints as parts of a sustainable agricultural development; and to discnss the methodological problems of controlled experiments vs. investigations in farmer's fields. LÄS MER