Search for dissertations about: "Nitrogen fixation"

Showing result 1 - 5 of 80 swedish dissertations containing the words Nitrogen fixation.

  2. 1. Marine nitrogen fixation : Cyanobacterial nitrogen fixation and the fate of new nitrogen in the Baltic Sea

    Author : Isabell Klawonn; Helle Ploug; Lasse Riemann; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biogeochemistry; nitrogen cycling; nitrogen fixation; cyanobacteria; Baltic Sea; Marine Ecology; marin ekologi;

    Abstract : Biogeochemical processes in the marine biosphere are important in global element cycling and greatly influence the gas composition of the Earth’s atmosphere. The nitrogen cycle is a key component of marine biogeochemical cycles. READ MORE

  4. 2. Biological nitrogen fixation : the effect of irridiated nitrogen gas on nitrogen fixation by Azotobacter

    Author : Bengt Zacharias; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : .... READ MORE

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

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

    Abstract : 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. READ MORE

  6. 4. Assessing reactive nitrogen flows in European agricultural systems

    Author : Rasmus Einarsson; Chalmers tekniska högskola; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; food; nitrogen indicator; nitrogen budget; nitrogen; agriculture; nitrogen footprint; uncertainties;

    Abstract : In most ecosystems, nitrogen is a scarce and growth-limiting nutrient. Natural and anthropogenic processes convert unreactive atmospheric dinitrogen (N2) into reactive, bioavailable, nitrogen. READ MORE

  7. 5. Nitrogen fixation among marine bacterioplankton

    Author : Kjärstin H. Boström; Lasse Riemann; Åke Hagström; Grieg Steward; Högskolan i Kalmar; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bacterioplankton; Nitrogen fixation; Bakterioplankton; Kvävefixering; Cyanobakterier; Kvävefixerande bakterier; Microbiology; Mikrobiologi; Mikrobiologi; Microbiology;

    Abstract : While bacterioplankton indisputably control vital biogeochemical paths in the cycling of carbon and nutrients in the world’s oceans, our knowledge about the functional and genetic diversity of bacterioplankton communities is negligible. In this thesis, molecular and more traditional microbiological methods were used to study the specific function of N2-fixation and in a general sense diversity of marine bacterioplankton species. READ MORE