Sökning: "species changes"

Visar resultat 16 - 20 av 964 avhandlingar innehållade orden species changes.

1. 16. Species interactions govern evolutionary and ecological effects of population harvesting

   Författare :Anna Gårdmark; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; population harvesting; species interactions; ecological community; Ekologi; Ecology; competition; predation; fisheries; spatial dynamics; maturation; population dynamics; life-history evolution; adaptation;

   Sammanfattning : Harvesting changes population abundance and can affect adaptation of several life-history traits. Harvesting can also have indirect effects ? effects on non-target species and secondary effects on target species ? because interactions between species in a community determine the relevant ecological and evolutionary feedback environment. LÄS MER

3. 17. Responses of boreal forest understory plant communities to climate and forestry

   Författare :Ditte Marie Christiansen; Kristoffer Hylander; Johan Ehrlén; Signe Normand; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; boreal forests; bryophytes; climate; climate change; community temperature index; demography; forest management; microclimate; plants; species interactions; species distributions; time-lags; transplant experiment; understory communities; Ecology and Evolution; ekologi och evolution;

   Sammanfattning : A warming climate is altering species distributions and community compositions. To understand and predict changes in species distributions to climate change, we often use species occurrences together with large-scale regional climate data. This can be problematic for several reasons. LÄS MER

4. 18. Species Responses to Environmental Fluctuations : impacts of food web interactions and noise color

   Författare :Sara Gudmundson; Uno Wennergren; Anna Eklöf; Sebastian Diehl; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Species constantly experience changes in their environmental conditions owing to natural or human induces reasons. Understanding how species respond to these fluctuations are important for ecology, especially given the ongoing climate change. Empirical studies have shown that species respond differently to the same disturbance. LÄS MER

5. 19. Disentangling Lecania

   Författare :Rikke Reese Næsborg; Leif Tibell; Stefan Ekman; Bengt Oxelman; Christian Printzen; Uppsala universitet; []
   Nyckelord :Biology; Crustose lichens; Phylogeny; Taxonomy; Morphology; New species; Phylogenetic diversity; Rare species; ITS; mt-SSU; RPB2; IGS; Biologi; Lecania; Ramalinaceae;

   Sammanfattning : This thesis focuses on phylogenetic, taxonomic, ecological, and conservation aspects of the crustose lichen genus Lecania (Ramalinaceae, lichenized Ascomycota). Lecania has previously been defined on basis of relatively few morphological characters, and the genus had never been treated in molecular phylogenies. LÄS MER

7. 20. Metapopulation and metacommunity processes, dispersal strategies and life-history trade-offs in epiphytes

   Författare :Swantje Löbel; Håkan Rydin; Tord Snäll; Lars E. Ericson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asexual; biodiversity; bryophytes; dispersal limitation; establishment; evolution of reproductive traits; germination; growth; habitat fragmentation; landscape dynamics; local processes; patch-tracking; pH; reproduction; species richness; species interactions; Other biology; Övrig biologi; Ecological Botany; Ekologisk botanik;

   Sammanfattning : The aim of this thesis was to increase knowledge about metapopulation and metacommunity processes in patchy, dynamic landscapes, using epiphytic bryophytes as a model system. Host trees and deciduous forest stands in the coniferous landscape are patchy, temporal and undergo changes in habitat quality during succession. LÄS MER