Sökning: "METAPOPULATION"

Visar resultat 1 - 5 av 31 avhandlingar innehållade ordet METAPOPULATION.

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

   Författare :Tord Snäll; Håkan Rydin; Johan Ehrlén; Christine Ray; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; plant; metapopulation; model; parameterization; connectivity; dispersal; colonization; extinction; epiphytic; bryophyte; lichen; boreal; fragmentation; Ekologi; Terrestrial; freshwater and marine ecology; 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

3. 2. 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

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

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

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

   Författare :Thomas Ranius; Biologiska institutionen; []
   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

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

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