Sökning: "soil nitrogen"

Visar resultat 1 - 5 av 179 avhandlingar innehållade orden soil nitrogen.

  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

  2. 2. Effects of forest fertilization on soil microorganisms

    Författare :Kristina Arnebrant; Biologibiblioteket; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; forest soil; nitrogen fertilization; microfungi; ectomycorrhiza; ATP; microbial biomass; nitrogen translocation; pine; alder; Frankia;

    Sammanfattning : .... LÄS MER

  3. 3. Nutrient Limitation of Bacterial Growth in Soil

    Författare :Fredrik Demoling; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ekologi; Ecology; Fertilization; Bacteria; Soil; Fungi; Thymidine or Leucine incorporation; Growth limitation; Phosphorus; Nitrogen; Carbon;

    Sammanfattning : Lack of carbon has been assumed to be the most common limiting factor for bacterial growth in soil, although there are reports of limitation by nitrogen and phosphorus. I have studied nutrient limitation of bacterial growth in soil using a novel technique, where thymidine or leucine incorporation is used to detect changes in growth rates after adding nutrients. LÄS MER

  4. 4. 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

  5. 5. Soil tillage influences on soil mineral nitrogen and nitrate leaching in Swedish arable soils

    Författare :Åsa Myrbeck; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Leaching of nitrogen (N) is an unwanted effect of agriculture practices which contributes to eutrophication of surface waters. This thesis examined how soil tillage practices affect leaching losses of N from arable fields. LÄS MER