Sökning: "Lars Ericson"

Visar resultat 6 - 10 av 16 avhandlingar innehållade orden Lars Ericson.

1. 6. Epiphytic lichen responses to nitrogen deposition

   Författare :Otilia Johansson; Kristin Palmqvist; Johan Olofsson; Annika Nordin; Lars E Ericson; Peter Crittenden; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lichens; air pollution; nitrogen deposition; phosphorus; growth; chlorophyll a; boreal forest; field experiment; irrigation; carbon based secondary compounds; Lavar; luftföroreningar; alg; svamp; kväve; fosfor; skog; Terrestrial ecology; Terrestrisk ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Nitrogen (N) deposition has increased globally over the last 150 years and further increase is predicted for the future. Nitrogen is an important nutrient for lichens, involved in many processes in both photobiont and mycobiont.  However, N can be a stressor, causing many lichens and lichen communities to disappear with increased deposition. LÄS MER

3. 7. 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

4. 8. Colonisation and extinction of vascular plants on islands off the Swedish east coast

   Författare :Anders Löfgren; Lars Ericson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; plants; ecological succession; colonizing ability; population dynamics; grasslands; islands; Sweden; plant ecology; Plant Ecology; växtekologi;

   Sammanfattning : Persistence of species is a function of colonisation and extinction among patches at a regional scale. A decrease in area and an increased isolation of suitable patches may result in a decreased colonisation rate and an increased extinction rate among species. LÄS MER

5. 9. Spatial patterns in the interaction between Salix triandra and associated parasites

   Författare :Lena Niemi; Anders Wennström; Lars Ericson; Keith Clay; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gonioctena linnaeana; host-parasite interactions; leaf beetle; local adaptation; Melampsora amygdalinae; phenolics; pathogens; plant host; secondary chemistry; Terrestrial ecology; Terrestisk ekologi;

   Sammanfattning : This thesis focuses on mechanisms and processes underlying spatial patterns of resistance and virulence and on local adaptations in plant–parasite interactions. The model system used comprises the plant host Salix triandra, the pathogenic rust fungus Melampsora amygdalinae, the leaf beetle Gonioctena linnaeana, and the galler Pontania triandrae. LÄS MER

7. 10. Colonization Patterns of Wood-inhabiting Fungi in Boreal Forest

   Författare :Jörgen Olsson; Lars Ericson; Jørund Rolstad; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wood-inhabiting fungi; colonization; dispersal; restoration fire; saproxylic beetles; conservation; forest management; boreal forest; Terrestrial ecology; Terrestisk ekologi;

   Sammanfattning : Forest management practices have changed the over-all structure of the Fennoscandian forest landscape resulting in a lack of suitable substrates for many wood-inhabiting species. The objectives of this thesis was to describe the colonization patterns of wood-inhabiting fungi, including the potential role of beetles as dispersal vectors, on different types of dead wood substrate and assess the importance of active measures in the forest landscape in order to restore biodiversity i. LÄS MER