Sökning: "environmental gradient"

Visar resultat 16 - 20 av 209 avhandlingar innehållade orden environmental gradient.

  1. 16. Effects of inorganic nitrogen and organic carbon on pelagic food webs in boreal lakes

    Författare :Anne Deininger; Ann-Kristin Bergström; Jan Karlsson; Antonia Liess; Carolyn L. Faithfull; John A. Downing; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; autochthony; basal production; boreal; global change; dissolved organic carbon; food web efficiency; N deposition; phytoplankton; seston stoichiometry; whole lake enrichment; zooplankton; limnologi; Limnology;

    Sammanfattning : Anthropogenic activities are increasing inorganic nitrogen (N) loadings to lakes in the northern hemisphere. In many boreal lakes phytoplankton are N limited, wherefore enhanced N input may affect the productivity of pelagic food webs. LÄS MER

  3. 17. Modelling effects of climate change and forestry on weathering rates and base cation cycling in forest soils

    Författare :Veronika Kronnäs; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; weathering; forest; biogeochemistry; Dynamic Modelling; ForSAFE;

    Sammanfattning : Base cations are important in forest soils as nutrients for vegetation and protection against soil acidification. Today, base cations have been lost from soils through acidification and forest harvesting. With low levels in soils, temporary situations of deficiency could occur. LÄS MER

  4. 18. Development and Application of Methods based on DOAS and FTIR Absorption Spectroscopy for Atmospheric Research

    Författare :Bo Galle; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; open-path; nitrous oxide; DOAS; long-path absorption; landfill; methane; climate gases; ozone depletion; biogenic emissions; fugitive emissions; FTIR; ammonia;

    Sammanfattning : Over the past decades concern about the environmental impact on our atmosphere from human activities has been constantly increasing. From the recognition of local industrial pollution in the first part of this century, over regional scale problems related to urbanisation and growth of traffic systems to global environmental problems such as climate change and stratospheric ozone depletion. LÄS MER

  5. 19. Stormwater Ponds for Pollution Reduction

    Författare :Thomas Pettersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; suspended solids; reduction; pollution; stormwater pond; flow modelling; FEM; field measurements; heavy metals; nutrients;

    Sammanfattning : Stormwater transports particulate-bound and soluble pollution from urban areas to receiving waters during rain events. Measurements have shown that open detention ponds, originally used for flood control, effectively reduce stormwater pollutant load and have therefore been increasingly used for stormwater treatment. LÄS MER

  7. 20. Airborne Gravity Gradient, Magnetic and VLF datasets : Case studies of modelling, inversion and interpretation

    Författare :Sayyed Mohammad Abtahi; Thomas Kalscheuer; Laust Pedersen; Jochen Kamm; Thorkild Rasmussen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; VLF; gravity gradient; magnetic; airborne; inversion; non-uniqueness;

    Sammanfattning : Northern Sweden is one of the largest hosts for mineral resources in Europe and always has been an interesting area for researchers from various disciplines of Earth sciences. This dissertation is a comprehensive summary of three case study papers on airborne VLF, gravity gradient and magnetic data in the area. LÄS MER