Sökning: "B. pubescens"

Visar resultat 1 - 5 av 8 uppsatser innehållade orden B. pubescens.

  1. 1. Demography of Birch Populations across Scandinavia

    Master-uppsats, Uppsala universitet/Växtekologi och evolution; Uppsala universitet/Institutionen för biologisk grundutbildning

    Författare :Janek Sendrowski; [2022]
    Nyckelord :birch; betula; pubescens; pendula; betula pubescens; betula pendula; silver birch; downy birch; demography; population structure; distribution of fitness effects; DFE; dadi; UMAP; PCA; ADMIXTURE; polyDFE; ice age; glaciation; tree; boreal forest; climate change; adaption; tetraploid; diploid-tetraploid introgression; Scandinavia; genetic cluster; pipeline; snakemake; bioinformatics; reproducible; population genetics; postglacial population expansion; demographic history; FEEMS; site-frequency spectrum; SFS; last glacial maximum; LGM; workflow; python; population expansion; population growth; EST-SFS; 0-fold degenerate; 4-fold degenerate; maximum likelihood estimation; MLE; variant call format; VCF; single-nucleotide polymorphism; SNP;

    Sammanfattning : Boreal forests are particularly vulnerable to climate change, experiencing a much more drastic increase in temperatures and having a limited amount of more northern refugia. The trees making up these vast and important ecosystems already had to adapt previously to environmental pressures brought about by the repeated glaciations during past ice ages. LÄS MER

  3. 2. Reindeer induced changes in vegetation composition and plant traits on a tundra-forest border

    Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Femke Pijcke; [2019]
    Nyckelord :physical geography; ecosystem analysis; plant functional traits; nutrient allocation; grazing; reindeer; Earth and Environmental Sciences;

    Sammanfattning : Reindeer (Rangifer tarandus) are the most common large herbivores in the arctic. With a habitat spreading over the entire circumpolar region, they can have a substantial effect on plant species composition and ecosystem processes and functions. LÄS MER

  4. 3. Reforestation in the far north : comparing effects of the native tree species Betula pubescens and the non-native Pinus contorta in Iceland

    Master-uppsats, SLU/Dept. of Wildlife, Fish and Environmental Studies

    Författare :Elin Fries; [2017]
    Nyckelord :Iceland; non-native tree species; understory vegetation; P. contorta; B. pubescens;

    Sammanfattning : The use of non-native tree species in forestry is both praised and questioned. Foresters have often promoted their use, mainly because of higher growth rates, resilience to pests and diseases and improved survival under harsh conditions. LÄS MER

  5. 4. Effects of climate warming on the performance of three boreal tree seedling species in interaction with moss cover and fire history

    Master-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Maria-Theresa Jessen; [2017]
    Nyckelord :;

    Sammanfattning : Forest regeneration in the form of successful seedling establishment is a key factor for the persistence of a healthy forest ecosystem. Tree seedlings grow in a complex environment shaped by over- and understory and competition for light, nutrients and water. LÄS MER

  7. 5. Rätt björk på rätt mark : Visuell identifiering av naturligt föryngrad björk

    Kandidat-uppsats, Linnéuniversitetet/Institutionen för skog och träteknik (SOT)

    Författare :Kristofer Vestergaard; Dennis Askevik; [2017]
    Nyckelord :;

    Sammanfattning : The silver birch (Betula pendula Roth) and the downy birch (Betula pubescens Ehrh) are the most common broadleaved species in Swedish forests. Both species have a lot in common in appearance and are often misleadingly referred to simply as ”birch”. They have however different requirements and possibilities to grow on different sites. LÄS MER