Search for dissertations about: "tree migration"

Showing result 1 - 5 of 13 swedish dissertations containing the words tree migration.

  2. 1. Genetic variation in structured populations

    Author : Marina Rafajlovic; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; genetic variation; varying population size; effective population size; mutation; recombination; migration; multiple paternity; geographic structure; tests of neutrality; gene tree; species tree;

    Abstract : It is widely acknowledged that the process of speciation in the presence of gene flow between different ecotypes is common in nature. However, the mechanisms underlying speciation are not understood. READ MORE

  4. 2. Extending dynamic vegetation models to simulate range shifts

    Author : Deborah Zani; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; dynamic vegetation model; range shift; migration; paleovegetation;

    Abstract : In response to rapid climate change and increasing human pressure, a wide variety of taxa have shifted their distribution in the past decades (range shift), with important consequences for ecosystem services and human health and economy. However, it is not yet clear whether most species will be able to track their favourable habitats or lag behind the climate signal (migration lag). READ MORE

  5. 3. The Holocene Spread of Spruce in Scandinavia

    Author : Thomas Giesecke; Keith Bennett; Richard Bradshaw; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Quaternary geology; Picea abies; pollen analyses; tree migration; population dynamics; Kvartärgeologi; Quaternary geology; Kvartärgeologi;

    Abstract : The Holocene spread of Picea abies in Scandinavia provides an excellent opportunity for detailed study of the dynamics of tree spread and population expansion. Early- and mid-Holocene macrofossil evidence for the presence of Picea abies in Scandinavia has questioned traditional interpretations of the timing and direction of its spread. READ MORE

  6. 4. Population biology and conservation of beetles and pseudoscorpions associated with hollow oaks

    Author : Thomas Ranius; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Systematic zoology; wood mould; tree hollow; pseudoscorpion; population variability; Osmoderma eremita; metapopulation; mark-recapture; habitat fragmentation; genetic structure; dispersal; beetle; computer simulation; taxonomy; zoogeography; Zoologisk systematik; djurgeografi;

    Abstract : Many species associated with old trees are threatened, as this habitat has decreased severely in Europe during the last 200 years. In old oaks, hollows with wood mould often form in the trunks and these harbour a specialized fauna mainly consisting of beetles, flies and pseudoscorpions. READ MORE

  7. 5. Vegetation and land-use in the Småland Uplands, southern Sweden, during the last 6000 years

    Author : Per Lagerås; Kvartärgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Geologi; physical geography; Sweden; Geology; Småland Uplands; land-use history; pollen analysis; Holocene vegetation history; mineral magnetic analysis; AMS dating; clearance cairns; hay production; shifting cultivation; Picea migration; slash-and-burn cultivation; fysisk geografi;

    Abstract : Palaeoecological methods were applied to peat and sediment cores recovered from one bog (Bråtamossen) and two lakes (Avegöl and Femtingagölen) in the Småland Uplands, southern Sweden. The general aim was to reconstruct the landuse and vegetation history for the last 6000 years in this agriculturally marginal region. READ MORE