Search for dissertations about: "mountain tundra"

Showing result 1 - 5 of 11 swedish dissertations containing the words mountain tundra.

  2. 1. Spatial and temporal population dynamics in the mountain tundra – mesopredator and prey

    Author : Rasmus Erlandsson; Anders Angerbjörn; Dennis Murray; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; population dynamics; cyclic; mountain tundra; arctic fox; Norwegian lemming; small rodents; mesopredator; predation; survival; reproduction; zoologisk ekologi; Animal Ecology;

    Abstract : It is well known that competition, predation and fluctuating food resources can have strong effect on individual fitness and population dynamics. The complexity of natural systems can make it complicate to disentangle those processes, but environments with relatively simple food webs, and strong cyclic population dynamics offer contrasting conditions resembling experimental treatments. READ MORE

  4. 2. Soil Organic Matter Dynamics and Methane Fluxes at the Forest – Tundra Ecotone in Fennoscandia

    Author : Sofie Sjögersten; Gaius Shaver; Uppsala universitet; []
    Keywords : Decomposition; forest – tundra ecotone; environmental change; Fennoscandia; methane; soil organic matter; subarctic.; naturgeografi; Physical Geography;

    Abstract : This thesis presents results from several studies that have focused on the carbon and nutrient dynamics in soils at the forest – tundra ecotone in Fennoscandia. The main objectives of the study were: (i) to investigate the links between the physical environment, above-ground vegetation communities, soil carbon storage, nutrient status and the chemical composition of the soil organic matter (SOM), and (ii) to quantify trace gas fluxes (methane and carbon dioxide) between mesic soils and the atmosphere. READ MORE

  5. 3. Spatial and temporal dynamics of subarctic birch forest carbon exchange

    Author : Michal Heliasz; Institutionen för naturgeografi och ekosystemvetenskap; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; mountain birch; eddy covariance; carbon budget; insect outbreak; forest expansion; temporal variability; spatial variability;

    Abstract : High northern latitudes are of special importance for the global carbon budget as they store large amounts of organic matter in the soil and are expected to be the most strongly affected by climate change. Here we investigate carbon exchange in the subarctic mountain birch forest growing on the limit where tree growth is possible. READ MORE

  6. 4. Plant Species Composition and Diversity in Cliff and Mountain Ecosystems

    Author : Henrik Antonsson; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; cliff ecology; bryophytes; biodiversity; beta diversity; dispersal; facilitation; nurse plant; plant-plant interactions; Silene acaulis; stress;

    Abstract : Ecosystems today are under increasing pressure from a rapidly changing climate, changes in land-use, habitat fragmentation and degradation and increasing anthropogenic disturbance. Studying drivers of biodiversity patterns is of increasing importance for understanding the dynamics of communities and their reactions and adaptation to changes in the future. READ MORE

  7. 5. Animal movement on short and long time scales and the effect on genetic diversity in cold-adapted species

    Author : Vendela Kempe Lagerholm; Love Dalén; Anders Angerbjörn; Bensch Staffan; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Abstract : The genetic diversity in modern species is strongly affected by contemporary gene flow between populations, which in turn is governed by individual dispersal capacities and barriers in the landscape. However, current patterns of variation have also been shaped by movement over longer time-scales, such as the successive shifts in species distributions that have occurred during past climate changes. READ MORE