Search for dissertations about: "nitrogen use efficiency"

Showing result 1 - 5 of 89 swedish dissertations containing the words nitrogen use efficiency.

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

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

    Abstract : 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. READ MORE

  4. 2. Nutrient cycling in agroecosystems: nitrogen cycling in southern Sweden in the 1850s and two Tanzanian villages in the 1990s

    Author : Lars-Erik Williams; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; nutrient; nutrient model; nutrient cycling; nitrogen fixation; nitrogen budget; mixed system; miombo; manure; livestock; land use; historical system; food production; efficiency; crops; agroecosystem; carrying capacity; phosphorus; Scania; sustainability; Plant ecology; Växtekologi;

    Abstract : This study presents a general model for analysing nutrient cycling in agroecosystems. The focus is on food production intensity, human carrying capacity, sustainability and efficiency. The model can be used on systems including different kinds of land uses, which makes it applicable for studies on different scales. READ MORE

  5. 3. SBR-technology - use and potential applications for treatment of cold wastewater

    Author : Stig Morling; Elzbieta Plaza; Jörgen Hanaeus; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intermittent operation; Water temperature; nitrogen; phosphorus; SBR; reaction rates; Environmental engineering; Miljöteknik;

    Abstract : Biological nutrient removal is used as an indicator of SBR performance at nine different SBRplants operated for a long period at low water temperatures (5 – 10oC). Typically needed aeratedSRT (Solids Residence Time) for complete nitrification is found to be in the range of 6 – 10 days. READ MORE

  6. 4. Physical process effects on catchment-scale pollutant transport-attenuation, coastal loading and abatement efficiency

    Author : Georg Lindgren; Georgia Destouni; Roko Andricevic; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Efficient pollutant load abatement; groundwater-surface water interactions; biogeochemical cycles; nitrogen; Lagrangian stochastic travel time approach; GIS; Hydrology; Hydrologi;

    Abstract : Pollutants follow various subsurface and surface water pathways from sources within a catchment to its outlet and may cause detrimental effects on downstream water quality and ecosystems. Along their different transport pathways through a catchment, pollutants may be attenuated subject to different physical and biogeochemical processes. READ MORE

  7. 5. Carbon Dioxide and Water Vapour Exchange within a Norway Spruce Canopy

    Author : Lasse Tarvainen; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; nitrogen allocation; optimality; stomatal conductance; photosynthesis; resource use efficiency; stem respiration; conifer;

    Abstract : Terrestrial ecosystems can act both as sinks and sources in the global carbon cycle. Forests are an important part of this system and a good understanding of their carbon balance is essential for assessments of the future climate and for evaluating mitigation strategies. READ MORE