Sökning: "phosphorus nitrogen"

Visar resultat 26 - 30 av 167 avhandlingar innehållade orden phosphorus nitrogen.

  1. 26. Soil phosphorus – a multidimensional resource that plays an important role for grassland plant species richness

    Författare :Jakob Sandberg; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; niche dimension; nutrient limitation; niche differentiation; competition; soil nitrogen; soil phosphorus; plant diversity; species richness; Grassland; land use; landscape scale;

    Sammanfattning : The semi-natural grassland habitats contain an important part of the plant diversity in Europe. Changes in farming practices have lead to drastic decreases in plant species richness. The aim of the present thesis is to contribute to the knowledge about mechanisms governing the plant species richness in grasslands with emphasis on soil nutrients. LÄS MER

  2. 27. Nitrogen-cycling tracing methods : Case studies at cold-climate mine sites in northern Sweden

    Författare :Lino Nilsson; Anders Widerlund; Andreas Bryhn; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied Geochemistry; Tillämpad geokemi;

    Sammanfattning : High nitrogen effluents from mine sites is an environmental issue which has received relatively little attention historically. In recent years a number of studies have showed the environmental effects of high nitrogen discharge to natural water bodies, which include local eutrophication, high risk of acute reducing conditions and changed species composition in the receiving waters. LÄS MER

  3. 28. Phosphorus recycling in brackish and marine environments - Sediment investigations in situ in the Baltic Sea and the By Fjord

    Författare :Lena Viktorsson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phosphorus; sediment; anoxia; Baltic Sea; By Fjord; benthic flux;

    Sammanfattning : The phosphorus load to the oceans from land started to increase since around 1950 when man started to mine phosphorus-mineral from phosphorus-rich soils and bedrock. The increased use of phosphorus fertilizers in agriculture together with the growth of coastal cities increased the load of phosphorus to the coastal ocean where plankton production flourished. LÄS MER

  4. 29. Systems Perspectives on Modelling and Managing Future Anthropogenic Emissions in Urban Areas : Nitrogen, Phosphorus and Carbon Studies in Stockholm, Sweden

    Författare :Jiechen Wu; Maria E. Malmström; Daniel Franzén; Daniel Müller; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Anthropogenic emissions; Urban development; Future; Substance flow analysis SFA ; DPSIR.;

    Sammanfattning : Managing anthropogenic emissions in urban areas is a major challenge in sustainable environmental development for cities, and future changes and increasing urbanisation may increase this challenge. Systems perspectives have become increasingly important in helping urban managers understand how different changes may alter future emissions and whether current management strategies can efficiently manage these emissions. LÄS MER

  5. 30. Nitrogen effluents from mine sites in northern Sweden : nitrogen transformations and limiting nutrient in receiving waters

    Författare :Sara Chlot; Anders Lundkvist; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Sammanfattning : Process water discharged from mine sites may contain elevated concentrations of nitrogen (N) and phosphorus (P), which both are nutrients for algae and aquatic plants. Thus, discharge of nutrient rich mine water can result in algal blooms, eutrophication, oxygen deficiency and changed species composition in the receiving waters. LÄS MER