Sökning: "Nitrogen Leaching"

Visar resultat 1 - 5 av 44 avhandlingar innehållade orden Nitrogen Leaching.

  1. 1. Nitrogen Losses from a Clay-rich Soil used for Cereal Production in south-western Sweden

    Författare :Magdalena Wallmann; Göteborgs universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; nitrogen; fertilisers; soil; nitrous oxide; nitrogen leaching; 15N; nitrogen use efficiency; nitrogen budget; agriculture; Sweden;

    Sammanfattning : Addition of fertiliser nitrogen (N) in crop production increases yields and protein contents, but all is not taken up by the crop. Instead, some of the N is lost to air and waters, contributing e.g. to climate change, stratospheric ozone depletion, eutrophication and acidification. LÄS MER

  3. 2. Microbial mobilization and immobilization of soil nitrogen

    Författare :Per Bengtson; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; growth rate; microbial activity; respiration; assimilation; immobilization; Nitrogen; mineralization;

    Sammanfattning : Microorganisms in forest ecosystems normally recycle nitrogen (N), such that gaseous losses and leaching are limited. Mobilization of organic N, including microbial N, and immobilization of inorganic N, especially NH4+, are the quantitatively most important N transformation processes. Various factors influence their rates, e.g. LÄS MER

  4. 3. External Mycelia of Mycorrhizal Fungi - responses to elevated N in forest ecosystems

    Författare :Lars Ola Nilsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ericoid; arbuscular; mycorrhiza; nitrogen; deposition; fertilisation; nitrate leaching; retention; field; forest; Quercus; deciduous; Plant ecology; Växtekologi; mykologi; virologi; bakteriologi; mycology; Microbiology; External mycelia; ectomycorrhiza; Mikrobiologi; bacteriology; virology;

    Sammanfattning : Most plants live in symbiosis with mycorrhizal fungi. Mycorrhizal roots constitute the interface between the plant and the soil, and almost every fine root of forest trees in nitrogen-limited boreal and temperate forests is colonised by ectomycorrhizal (EM) fungi. LÄS MER

  5. 4. Ectomycorrhizal fungi: Their role in nitrogen retention and carbon sequestration in northern coniferous forests

    Författare :Adam Bahr; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ectomycorrhizal fungi; Carbon sequestration; Nitrogen deposition; Nitrogen leakage; Field survey; Boreo-nemoral forest; Boreal Forest; Ergosterol; Free ergosterol; Mesh-bags; Multivariate analysis;

    Sammanfattning : Almost all northern forest tree species live in symbioses with ectomycorrhizal fungi (EMF). The trees allocate up to half of the photoassimilated carbon (C) through the roots to EMF. In return EMF deliver nutrients from both inorganic and organic sources in the soil, as well as water. LÄS MER

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

    Författare :Stefan Olin; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Carbon; Nitrogen; DVM; Ecosystem modelling; Cropland; Management; Yields;

    Sammanfattning : 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. LÄS MER