Search for dissertations about: "Lavar"
Showing result 1 - 5 of 9 swedish dissertations containing the word Lavar.
-
1. Epiphytic lichen responses to nitrogen deposition
Abstract : 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. READ MORE
-
2. Lichens and air pollution : a study of cryptogamic epiphytes and environment in the Stockholm region
Abstract : .... READ MORE
-
3. Anatomy and taxonomy of cetrarioid lichens
Abstract : The anatomy of the cetrarioid lichens (Parmeliaceae) has been studied, and the taxonomy revised. Special attention has been paid to reproductive structures, in particular the asci and pycnoconidia. Two types of asci are recognized. The Cetraria type is narrowly clavate, bears an amyloid ring structure in the tholus, and has a small axial body. READ MORE
-
4. Modeling lichen performance in relation to climate : scaling from thalli to landscapes
Abstract : Lichens can colonize nearly all terrestrial habitats on earth and are functionally important in many ecosystems. Being poikilohydric, their active growth periods are restricted to periods when the thallus is hydrated from atmospheric water sources, such as rain, fog and high relative humidity. READ MORE
-
5. Plants go with the flow : predicting spatial distribution of plant species in the boreal forest
Abstract : The main objectives of this thesis are to study if a topographic wetness index (TWI) could be used as a tool for predicting the spatial distribution of vascular plant species richness in the boreal forest as well as to study congruence in species richness between vascular plants, liverworts, mosses and lichens. A wetness index ln(a/tanβ) based on topography was used to assign a specific TWI-value to every 20 x 20m grid in two 25 km2 boreal forest landscapes (differing in average soil pH) in northern Sweden. READ MORE