Sökning: "soil seed banks"

Hittade 5 avhandlingar innehållade orden soil seed banks.

  1. 1. Long-term studies of succession : Colonisation and seed banks

    Författare :Ulf Grandin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ellenberg indicator values; genetic variation; long-term study; Lythrum salicaria; Moehringia trinervia; primary succession; seed bank; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER

  3. 2. Ecology and evolution of local adaptation in Arabidopsis thaliana

    Författare :Giulia Zacchello; Jon Ågren; Xavier Picó; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arabidopsis thaliana; germination time; natural populations; Near isogenic lines; reciprocal transplants; seed bank; seed dormancy; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Sammanfattning : In this thesis, I investigate the ecological genetics of local adaptation in the annual herb Arabidopsis thaliana with the aim to identify key traits, agents of selection, and genomic regions contributing to adaptive differentiation. The thesis focuses on adaptive differentiation in timing of germination and seed dormancy between populations located close to the southern and northern range margins in Europe. LÄS MER

  4. 3. Ecological rehabilitation of degraded hill slopes in southern Wello, Ethiopia

    Författare :Kebrom Tekle; Ingvar Backéus; Eddy van der Maarel; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Classification; hillside closures; intercept lengths; land cover; land degradation; local participation; natural regeneration; ordination; permanent plots; soil seed banks; succession; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Ecological Botany; Ekologisk botanik;

    Sammanfattning : Clearing of vegetation has left large areas of southern Wello (Ethiopia) at a high risk ofland degradation. In this study, the causes, extent and consequences of land degradationproblems are reviewed. To see land cover changes, aerial photographs from 1958 and1986 were compared with the help of a GIS procedure. LÄS MER

  5. 4. Small-scale pattern and mobility of plant species in Alvar grassland

    Författare :Xiaobing Dai; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; association analysis; cattle dung; decomposition; limestone grassland; Gland; PASFRAN; soil seed bank type; Sweden; turn-around time; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Studies of the small-scale pattern, mobility of plant species and the effects of cattle dung deposition and decomposition on the soil seed banks and the above-ground vegetation were carried out in an alvar limestone grassland in Gettlinge, on the Baltic island of Öland, Sweden.A new method for pattern detection using transect data Patch Size Frequency Analysis (PASFRAN), was developed. LÄS MER

  7. 5. Ecology of the fire-dependent forest herbs Geranium bohemicum and G. lanuginosum in Sweden

    Författare :Lotta Risberg; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Geranium bohemicum and G. lanuginosum are the only plant species in Sweden considered fire-dependent, because of their heat-triggered germination. Both are today threatened due to effective fire suppression. An aim with this study was to elucidate their population ecology. LÄS MER