Search for dissertations about: "Nitrogen Cycle"

Showing result 1 - 5 of 76 swedish dissertations containing the words Nitrogen Cycle.

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

    University dissertation from Stockholm : Department of Ecology, Environment and Plant Sciences, Stockholm University

    Author : Isabell Klawonn; Stockholms universitet.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biogeochemistry; nitrogen cycling; nitrogen fixation; cyanobacteria; Baltic Sea; marin ekologi; Marine Ecology;

    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

  2. 2. Control factors of the marine nitrogen cycle The role of meiofauna, macrofauna, oxygen and aggregates

    University dissertation from Stockholm : Department of Geological Sciences, Stockholm University

    Author : Stefano Bonaglia; Stockholms universitet.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nitrogen cycle; denitrification; DNRA; anammox; anoxia; hypoxia; eutrophication; meiofauna; macrofauna; aggregates; cyanobacteria; Baltic Sea; geokemi; Geochemistry;

    Abstract : The ocean is the most extended biome present on our planet. Recent decades have seen a dramatic increase in the number and gravity of threats impacting the ocean, including discharge of pollutants, cultural eutrophication and spread of alien species. READ MORE

  3. 3. Soil-living archaea: Influence of pH, carbon and nitrogen on their abundance and activity

    University dissertation from Department of Biology, Lund University

    Author : Anna Sterngren; Lunds universitet.; Lund University.; Lunds universitet.; Lund University.; [2014]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ammonia-oxidizing archaea; Archaea; soil; AOA; AOB; root exudates; gross nitrification; qPCR; pH; carbon cycle; nitrogen cycle;

    Abstract : During the last decade it has been discovered that around 2% of the soil-living prokaryotes belong to the domain Archaea. In many soils the most abundant archaeal group is the ammonia-oxidizing archaea (AOA) that, in addition to ammonia-oxidizing bacteria (AOB), preform the first and rate-limiting step in the nitrification process. READ MORE

  4. 4. Responses of peatland vegetation to enhanced nitrogen

    University dissertation from Umeå : Ekologi, miljö och geovetenskap

    Author : Magdalena Wiedermann; Umeå universitet.; [2008]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sphagnum; nitrogen; peatlands; soluble amino acids; gradient study; field experiment; NATURAL SCIENCES Biology; NATURVETENSKAP Biologi;

    Abstract : Human alteration of the global nitrogen (N) cycle has had major impacts on naturally N-limited ecosystems worldwide. Peatlands, dominated by peat mosses, Sphagnum species, represent one such sensitive ecosystem. READ MORE

  5. 5. Ecosystems in the Anthropocene: the role of cropland management for carbon and nitrogen cycle processes

    University dissertation from Department of Physical Geography and Ecosystem Science, Lund University

    Author : Stefan Olin; Lunds universitet.; Lund University.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nitrogen; Carbon; DVM; Ecosystem modelling; Cropland; Management; Yields;

    Abstract : Through deforestation and conversion of natural ecosystems to croplands and pastures, have humans released vast amounts of carbon (C) dioxide (CO2) into the atmosphere. Roughly one third of the cumulative anthropogenic emissions until today stem from these practices, the remainder being mostly due to fossil fuel combustion. READ MORE