Avancerad sökning

Hittade 5 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Methane dynamics in northern wetlands: Significance of vascular plants

    Författare :Anna Joabsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aquatic ecology; marine biology; Hydrobiology; Växtekologi; Plant ecology; climate change; arctic wetlands; northern wetlands; plant-microbe interactions; methane emission; vascular plants; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

    Sammanfattning : The studies presented in Papers I to VI illustrate several different aspects of the impact of vascular plants on methane emissions from northern natural wetlands. The subject has been approached on different scales, ranging from the study of microbial substrates in the vicinity of a single plant root, to an attempt to extrapolate some of the results to the entire northern hemisphere north of 50°N. LÄS MER

  3. 2. Tundra meets atmosphere : Seasonal dynamics of trace gas exchange in the High Arctic

    Författare :Norbert Pirk; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic; tundra; methane; carbon dioxide;

    Sammanfattning : Arctic environments have experienced strong warming in recent decades, which is affecting the carbon cycle of tundra ecosystems.Degrading permafrost, diminishing snow cover, and changing hydrology are examples of ongoing processes that affect the land-atmosphere interactions and seasonal ecosystem dynamics. LÄS MER

  4. 3. Plant-soil-herbivore interactions in a high Arctic wetland - Feedbacks to the carbon cycle

    Författare :Julie Maria Falk; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic wetlands; carbon balance; herbivory; increased grazing pressure; methane fluxes; muskox exclusion; substrate avalibility; vegetation composition and density;

    Sammanfattning : Arctic ecosystems hold massive amounts of the global carbon in their soils and are of great importance for the global terrestrial exchange of greenhouse gases to the atmosphere. The arctic region has in general been acting as a C sink for the past 10000 years, however with climate change the C balance in some areas is shifting towards becoming a C source. LÄS MER

  5. 4. Hydrological spreading of metal pollution and wetlands as nature-based solutions

    Författare :Josefin Thorslund; Jerker Jarsjö; Mario Schirmer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical Geography; naturgeografi;

    Sammanfattning : The quality of the Earth’s water resources have deteriorated due to human impacts. A key scientific challenge is to understand, quantify and predict the water-borne spreading of pollutants at relevant scales for freshwater management and water quality restoration programs. LÄS MER

  7. 5. Geophysical Applications of Vegetation Modeling

    Författare :Jed O Kaplan; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Växtbiokemi; Plant biochemistry; CH4; CO2; stable isotopes; carbon cycle; wetland; ice core; methane; Holocene; mammoths; tundra; ice age; LGM; biogeography; biome; biogeochemistry; Vegetation model; Miljökemi; Physical geography; geomorphology; pedology; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi;

    Sammanfattning : This thesis describes the development and selected applications of a global vegetation model, BIOME4. The model is applied to problems in high-latitude vegetation distribution and climate, trace gas production, and isotope biogeochemistry. LÄS MER