Sökning: "Lars E Ericson"
Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Lars E Ericson.
1. Epiphytic lichen responses to nitrogen deposition
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
2. Metapopulation and metacommunity processes, dispersal strategies and life-history trade-offs in epiphytes
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
3. Interactions between natural enemies and the dioecious herb Silene dioica
Sammanfattning : About 6% of all angiosperms are dioecious. This separation of sexual function to male and female individuals, and the fundamentally different patterns of reproductive resource allocation that follows that separation, are thought to have important ecological and evolutionary consequences for plant enemy interactions. LÄS MER
4. Colonization Patterns of Wood-inhabiting Fungi in Boreal Forest
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
5. Systemic fungal diseases in natural plant populations
Sammanfattning : The purpose of this thesis was to study interactions between systemic fungal diseases and perennial plants. Using the systemic rust Puccinia minussensis on the host plant Lactuca sibirica, and the rust Puccinia pulsatillae on the host plant Pulsatilla pratensis, this thesis focused on: (i) the effects of systemic diseases on their hosts (ii) host and pathogen responses to abiotic factors, (iii) the importance of life history strategies for understanding host-pathogen interactions, and (iv) the evolutionary consequences of living in close associations. LÄS MER