Avancerad sökning

Visar resultat 1 - 5 av 7 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. The Holocene Spread of Spruce in Scandinavia

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

    Sammanfattning : 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. LÄS MER

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

    Författare :Per Lagerås; Kvartärgeologi; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  4. 3. Conifer Evolution, from Demography and Local Adaptation to Evolutionary Rates : Examples from the Picea genus

    Författare :Jun Chen; Martin Lascoux; Ulf Lagercrantz; Matt Olson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Speciation; Demographics; clinal variation; convergent evolution; transcriptome; small regulatory RNA; Biologi med inriktning mot evolutionär funktionsgenomik; Biology with specialization in Evolutionary Functional Genomics; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

    Sammanfattning : Evolutionary process can be inferred at three different levels: the species level, the population level and the molecular level. In this thesis, I applied approaches at these three levels and aimed to get a comprehensive picture of conifer evolution, from speciation and demography to geographic variation and local adaptation, and then to the molecular evolution of proteins and small regulatory RNAs. LÄS MER

  5. 4. The Late Holocene history of beech Fagus sylvatica and Norway spruce Picea abies at stand-scale in southern Sweden

    Författare :Leif Björkman; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; physical geography; Geology; south Sweden; Late Holocene; succession; disturbance; forest history; forest continuity; population dynamics; immigration; palaeoecology; pollen analysis; Fagus sylvatica; Picea abies; Geologi; fysisk geografi; Palaeobotany; phylogeny; palynology; Paleobotanik; fylogeni; palynologi;

    Sammanfattning : High resolution pollen analysis was carried out on five peat profiles from small forest hollows at four sites in southern Sweden. The general aim was to investigate the establishment of Fagus sylvatica and Picea abies at stand-scale. LÄS MER

  7. 5. Adaptive Evolution and Demographic History of Norway Spruce (Picea Abies)

    Författare :Thomas Källman; Peter Tiffin; Uppsala universitet; []
    Nyckelord :;

    Sammanfattning : One of the major challenges in evolutionary biology is to determine the genetic basis of adaptive variation. In Norway spruce (Picea abies) the timing of bud set shows a very strong latitudinal cline despite a very low genetic differentiation between populations. LÄS MER