Sökning: "metapopulation"

Visar resultat 1 - 5 av 26 avhandlingar innehållade ordet metapopulation.

  1. 1. Distribution Patterns and Metapopulation Dynamics of Epiphytic Mosses and Lichens

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Tord Snäll; Uppsala universitet.; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; plant; metapopulation; model; parameterization; connectivity; dispersal; colonization; extinction; epiphytic; bryophyte; lichen; boreal; fragmentation; Ekologi; NATURAL SCIENCES Biology Terrestrial; freshwater and marine ecology; NATURVETENSKAP Biologi Terrestisk; limnisk och marin ekologi;

    Sammanfattning : This thesis examines the relative importance of local conditions, dispersal and dynamics of the trees on epiphyte distribution patterns and colonization-extinction dynamics. Study species are the mosses Orthotrichum speciosum and O. obtusifolium, and the red-listed Neckera pennata. LÄS MER

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

    Detta är en avhandling från Jonas Hedin

    Författare :Jonas Hedin; [2003]
    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

  3. 3. Establishment, Growth and Population Dynamics in two Mosses of Old-growth Forests

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Karin Wiklund; Håkan Rydin; Staffan Karlsson; Lloyd Stark; [2004]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Buxbaumia viridis; Neckera pennata; bryophyte; pH; phosphorus; water potential; precipitation; metapopulation; environmental stochasticity; ecology; plant; Biologi; NATURAL SCIENCES Biology; NATURVETENSKAP Biologi;

    Sammanfattning : Biodiversity in forests depends on long canopy continuity and existence of different elements which function as substrates for varying organisms. Bryophytes often occupy specific substrates with a patchy distribution. LÄS MER

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

    Detta är en avhandling från Department of Zoology, Lund University

    Författare :Thomas Ranius; [2000]
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  5. 5. Population Dynamics and Conservation of the Sand Lizard (Lacerta agilis) on the Edge of its Range

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Sven-Åke Berglind; Pekka Pamilo; Per Sjögren-Gulve; Coulson Tim; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; demography; extinction; habitat; Lacerta agilis; management; metapopulation; peripheral populations; population dynamics; population viability analysis; reintroduction; reptiles; umbrella species; Ekologi; NATURAL SCIENCES Biology Terrestrial; freshwater and marine ecology; NATURVETENSKAP Biologi Terrestisk; limnisk och marin ekologi;

    Sammanfattning : The sand lizard (Lacerta agilis) reaches the northern periphery of its distribution in south-central Sweden, where small, isolated relict populations occur in pine heath forests on sandy sediments. Modern forestry and fire suppression have reduced the amount of suitable open habitat for the species in this area and seem to be important for its decline. LÄS MER