Sökning: "Biogeochemistry"

Visar resultat 6 - 10 av 20 uppsatser innehållade ordet Biogeochemistry.

  1. 6. Organic nitrogen and carbon in Swedish rivers : increasing trends from 1987-2017

    Kandidat-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Maya Ahlgren; [2018]
    Nyckelord :total organic nitrogen; total organic carbon; eutrophication; Sweden; dissolved organic carbon; brownification; Pearson’s correlation; Baltic Sea; Earth and Environmental Sciences;

    Sammanfattning : In the past decades, increased organic carbon concentrations have been reported from freshwaters across the Northern Hemisphere. However, there is little knowledge regarding whether or not these changes are linked to increasing concentrations of organic nitrogen. LÄS MER

  3. 7. Variability and regulation of the planktonic respiratory quotient in a eutrophic lake (Lake Vombsjön) in summer 2016

    Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Karla Münzner; [2017]
    Nyckelord :Physical geography and ecosystem analysis; biogeochemistry; bacterioplankton respiration; eutrophic lake; carbon cycling; Lake Vombsjön; Earth and Environmental Sciences;

    Sammanfattning : Bacterial respiration and biomass growth are important processes for carbon cycling in freshwater ecosystems and bacterial respiration is often quantified from measured O2 concentrations by using a respiratory quotient (RQ=O2 consumed to produce CO2, in moles) of 1. Recent studies have shown, however, that RQs can vary a lot in different aquatic ecosystems (0. LÄS MER

  4. 8. Geochemistry of stream plants and its statistical relations to soil- and bedrock geology, slope directions and till geochemistry : a GIS-analysis of small catchments in northern Sweden

    Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Harry Eriksson; [2017]
    Nyckelord :Biogeochemistry; GIS; Physical Geography and Ecosystem analysis; Geographical Information Systems; Geochemistry; Catchments; Drainage areas; Earth and Environmental Sciences;

    Sammanfattning : Subaquatic mosses and stream plants have been recognized as suitable sample media for detection of geochemical variations in their surrounding environments. These plants were originally used in search for mineral deposits but later on also for detection of environmental pollution. LÄS MER

  5. 9. Organic matter properties and their relation to phosphorus and nitrogen concentrations in Swedish agricultural streams

    Master-uppsats, SLU/Dept. of Soil and Environment

    Författare :Betty Ehnvall; [2017]
    Nyckelord :dissolved organic matter; excitation-emission fluorescence spectroscopy; absorbance spectroscopy; eutrophication; biogeochemistry; absorbance index; fluorescence index;

    Sammanfattning : Many agricultural streams in Sweden exhibit high concentrations of nitrogen, phosphorus, suspended sediments and dissolved organic matter (DOM). Together these substances cause eutrophication in streams, rivers and eventually the Baltic Sea. The interactions between different fractions of DOM and nutrients are not very well understood. LÄS MER

  7. 10. Effect of historical land-use on lake-water carbon and geochemistry: : A multi-proxy study of two lake sediment profiles in Dalarna throughout the Holocene

    Master-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Florian Muthreich; [2016]
    Nyckelord :lake-water TOC; summer farming; forest grazing; sediment geochemistry;

    Sammanfattning : This study examines changes in lake-water total organic carbon (LW-TOC) and lake sediment geochemistry in two lakes, Stångtjärnen and Holtjärnen in (Dalarna, Sweden), during the Holocene and the role of the historic forest grazing and farming (fäbod-system). The aims of the study were to: 1. LÄS MER