Search for dissertations about: "tundra"

Showing result 1 - 5 of 68 swedish dissertations containing the word tundra.

  2. 1. Circumpolar impacts of herbivores on Arctic tundra vegetation

    Author : Elin Lindén; Johan Olofsson; Maja K. Sundqvist; Mariska te Beest; Elisabeth S. Bakker; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; herbivores; grazing; Arctic; circumpolar; tundra; vegetation; plant defence; secondary metabolites; shrub birch; exclosures; vegetation; species diversity; biology; biologi;

    Abstract : Arctic tundra vegetation provides many ecological services that have implications for the global climate. However, the tundra biome is currently changing in response to increasing temperatures. Herbivores may mitigate some of these responses to warming through their impact on Arctic vegetation. READ MORE

  4. 2. Population dynamics of tundra-living grey-sided voles

    Author : Per Ekerholm; Lauri Oksanen; Rolf Anker Ims; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Population dynamics; Tundra; Grey-sided vole; Cycles; Vole specialist predators; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; zooekologi; Animal Ecology;

    Abstract : This thesis deals with the dynamics of tundra living voles with emphasis on the most common one, the grey-sided vole (Clethrionomys rufocanus). The tundra area chosen for the study was Finnmarksvidda, a vast flatland in northernmost Norway. READ MORE

  5. 3. Land-atmosphere exchange of carbon in a high-Arctic wet tundra ecosystem

    Author : Torbern Tagesson; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; carbon; methane; carbon dioxide; climate change; Arctic; NDVI; NDWI; micrometeorology; remote sensing; chamber; tundra;

    Abstract : Arctic ecosystems play a key role in the terrestrial carbon (C) cycle, but spa-tially explicit data on the C exchange is scarce in these remote areas. The global warming is especially dominant in the Arctic, and these areas are vul-nerable to climate change. READ MORE

  6. 4. Tundra meets atmosphere : Seasonal dynamics of trace gas exchange in the High Arctic

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

    Abstract : 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. READ MORE

  7. 5. Phosphorus availability and microbial respiration across biomes : from plantation forest to tundra

    Author : Camilla Esberg; Reiner Giesler; David A. Wardle; Bente J. Graae; Dan Binkley; Umeå universitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phosphorus availability; microbial bioassay; soil respiration; microbial growth rate; Hedley fractionation; soil sorption; weathered soils; boreal forest; subarctic and tundra;

    Abstract : Phosphorus is the main limiting nutrient for plant growth in large areas of the world and the availability of phosphorus to plants and microbes can be strongly affected by soil properties. Even though the phosphorus cycle has been studied extensively, much remains unknown about the key processes governing phosphorus availability in different environments. READ MORE