Sökning: "Metapopulations"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet Metapopulations.

  1. 1. The importance of small forest set-asides for saproxylic biodiversity at stand- landscape- and regional scales

    Författare :Mari Therese Jönsson; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; boreal forest; colonization-extinction dynamics; dendrochronology; dead-wood dynamics; disturbance dynamics; forest history; fragmentation; metapopulations; national inventories; old-growth forest; picea abies; saproxylic species; set asides; spatiotemporal dynamics; stand reconstructions; tree mortality; woody debris; wood-decaying fungi; woodland key habitats; Biology; Biologi;

    Sammanfattning : .... LÄS MER

  3. 2. Butterfly Diversity and Dispersal in Fragmented Grasslands

    Författare :Erik Öckinger; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Naturvetenskap; Djurekologi; Animal ecology; Ekologi; Ecology; Lepidoptera; Landscape ecology; Insects; Species richness; Fragmentation; Mobility; Natural science; Source-sink dynamics; Metapopulations;

    Sammanfattning : During the last decades, the distribution and abundance of many European species of birds, plants and insects in agricultural landscapes have declined due to agricultural intensification. To be able to mitigate these declines, it is essential to know the relative importance on local and regional ecological processes on population persistence and patterns of species richness. LÄS MER

  4. 3. Metapopulations dynamics and sex-specific resource allocation in Silene dioica

    Författare :Elisabet Peedu; Pär Ingvarsson; Barbara Giles; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Silene dioica; Skeppvik Archipelago; Metapopulation Dynamics; Population Genetic Structuring; Genetic Diversity; Gene Flow; Sex-Specific Resource Allocation; Cost of Reproduction; Life-History Theory; Sexual Dimorphism; Reproductive Effort; biology; biologi; evolutionär genetik; evolutionary genetics; ekologisk botanik; Ecological Botany;

    Sammanfattning : Rising archipelagos provide unique settings for the study of the temporal and spatial dynamics of their biota. This offers the possibility to study the ecology and genetics of early successional processes; both between islands that differ in age and within islands when already established organisms have to keep pace with the changing environment. LÄS MER

  5. 4. Distribution and persistence of epiphyte metapopulations in dynamic landscapes

    Författare :Victor Johansson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Habitat loss is a major cause of species extinction. Old trees have declined, and this continues because of poor management. Examples are development of secondary woodland in semi-open grasslands, and lack of natural tree regeneration. We therefore can expect that species associated with old tree are declining. LÄS MER

  7. 5. Metapopulation ecology of Osmoderma eremita - dispersal, habitat quality and habitat history

    Författare :Jonas Hedin; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; extinction debt; habitat history; habitat quality; pheromone; telemetry; capture-mark-recapture; metapopulation; dispersal; oak; Osmoderma eremita; beetle; Animal ecology; Djurekologi;

    Sammanfattning : This thesis starts with a review of different biodiversity assessment methods in forests and the rest deals with the metapopulation ecology of Osmoderma eremita, a threatened beetle living in hollow trees. I concentrate on the effect of dispersal, habitat quality and habitat history for the presence, population size and future survival of this species. LÄS MER