Sökning: "increased grazing pressure"

Visar resultat 11 - 15 av 20 avhandlingar innehållade orden increased grazing pressure.

  1. 11. Food web dynamics in open and closed systems

    Författare :Johan Lövgren; Lennart Persson; Jonathan Chase; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; allochtonous input; cross habitat foraging; donor control; heterogeneity within trophic level; compensation; food web; littoral; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : This thesis is a summary of enclosure and microcosm experiments that aimed to study the impact of allochtonous subsidies on food web dynamics in a heterogeneous food web. In the enclosure studies, a three trophic level littoral food web was used. LÄS MER

  3. 12. Nature conservation, landscape change and indigenous rights : The role of Sámi reindeer herding for environmental objectives in the Swedish mountain landscape

    Författare :Carl Österlin; Ingrid Stjernquist; Peter Schlyter; Camilla Eriksson; Urban Emanuelsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Land use planning; Cumulative Effects; Reindeer herding; Natural resource extraction; Environmental Management; Physical Geography; naturgeografi;

    Sammanfattning : The 14th Swedish national environmental objective, ‘a Magnificent Mountain Landscape’, requires a mountain landscape characterized by reindeer grazing. The Swedish mountains landscape, part of the Scandes, has been shaped by traditional indigenous Sámi reindeer herding and its grazed environments are dependent on reindeer. LÄS MER

  4. 13. Promoting natural regeneration of oak by manipulating disturbance

    Författare :Linda Petersson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Oak regeneration is thought to be promoted by natural disturbance and past management practices that create semi-open conditions, such as periodic livestock grazing and lowintensity fire. The overall goal of this thesis was to examine whether disturbance factors can promote natural oak regeneration. LÄS MER

  5. 14. Natural and human-induced carbon storage variability in seagrass meadows

    Författare :Martin Dahl; Martin Gullström; Miguel A Mateo; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Blue carbon sequestration; Carbon storage variability; Seagrass meadows; Anthropogenic disturbances; Climate change; marin ekologi; Marine Ecology;

    Sammanfattning : Seagrasses are considered highly important CO2 sinks, with the capacity to store substantial quantities of organic carbon in the living biomass and sediments, and thereby acting as a buffer against climate change. In this thesis, I have studied carbon storage variability in temperate and tropical seagrass habitats and identified factors influencing this variation. LÄS MER

  7. 15. Carbon sequestration processes in tropical seagrass beds

    Författare :Liberatus Dominick Lyimo; Mats Björk; Martin Gullström; Mariam Hamis; Teresa Alcoverro; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Seagrass; Carbon sequestration; Carbon sink; Eutrophication; Productivity; Nitrous oxide; Methane; Greenhouse gases; Tropical; Eastern Africa; Plant Physiology; växtfysiologi;

    Sammanfattning : Seagrass meadows may play a substantial role in climate change mitigation as they are capable to sequester and store substantial amounts of anthropogenic carbon in plant biomass and, more importantly, in their underlying sediments. In this PhD thesis, the carbon-burial potential was assessed by quantifying the amount of organic carbon stored in different seagrass meadows, each dominated by one of the four major seagrass species in the Western Indian Ocean region. LÄS MER