Search for dissertations about: "Tundra vegetation"

Showing result 16 - 20 of 33 swedish dissertations containing the words Tundra vegetation.

  2. 16. Mechanisms of below-ground carbon cycling in subarctic ecosystems

    Author : Maria Olsrud; Institutionen för naturgeografi och ekosystemvetenskap; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi; pedology; geomorphology; Physical geography; subarctic tundra; phosphorous mobilization; organic acids; open top chamber experiment; 15N natural abundance; Ericoid mycorrhizas; global change; 14C pulse-labelling; Carbon allocation;

    Abstract : Some components of the below-ground carbon (C) cycle in terrestrial ecosystems are still poorly understood. A better understanding will be necessary to predict adequately the impacts of global change factors on C cycling and storage, especially in high-latitude ecosystems, where much of the C is stored below-ground. READ MORE

  4. 17. Temporal and spatial variability of carbon cycling in a subarctic landscape

    Author : Torbjörn Johansson; Institutionen för naturgeografi och ekosystemvetenskap; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Geologi; physical geography; Geology; Växtekologi; Plant ecology; Permafrost; Herbivory; Subarctic; Aerial photography; Vegetation change; Carbon balance; fysisk geografi;

    Abstract : This thesis deals with the carbon balance in a subarctic landscape at different temporal and spatial scales. Its focus is mainly on the peatland and mountain birch forest (Betula pubescens ssp. czerepanovii) ecosystems within the Abisko area in northernmost Sweden. This is an area with a temperature close to the 0 OC mean annual isotherm. READ MORE

  5. 18. Nitrogen and phosphorus dynamics across an elevational gradient in a Swedish subarctic tundra

    Author : Maja Sundqvist; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Rising temperatures associated with global climate change are likely to drive major shifts in plant and soil properties as well as plant-soil linkages that govern key ecosystem processes in subarctic tundra. However, the tundra landscape is not homogenous, but instead consists of a mosaic of vegetation types which differ greatly in vegetation characteristics and soil fertility. READ MORE

  6. 19. The role of herbivores in mediating responses of tundra ecosystems to climate change

    Author : Elina Kaarlejärvi; Johan Olofsson; Anu Eskelinen; Jon Moen; Eric Post; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Climate change; warming; grazer; Rangifer; Lemmus lemmus; species distribution; biotic interactions; altitude; Environmental Science; miljövetenskap;

    Abstract : The Arctic areas are warming more rapidly than other parts of the world. Increasing temperatures are predicted to result in shrubification, higher productivity, declining species diversity and new species invasions to the tundra. READ MORE

  7. 20. On the role of terrestrial ecosystems in a changing Arctic

    Author : Adrian Gustafson; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Northern high latitudes; Arctic climate change; climate-vegetation feedbacks; shrubs; shrubification; treeline migration; LPJ-GUESS; RCA-GUESS; nitrogen; carbon; Northern high latitudes; Arctic climate change; climate-vegetation feedbacks; shrubs; shrubification; treeline migration; LPJ-GUESS; RCA-GUESS; Nitrogen; Carbon;

    Abstract : The global temperature rise is proportional to the cumulative amount of CO2 emissions to the atmosphere. This observation is consistent between climate models and historical observations. READ MORE