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Visar resultat 1 - 5 av 82 avhandlingar som matchar ovanstående sökkriterier.
1. Island biogeography of young land uplift islands - viewed through the lens of bryophytes in a northern Swedish archipelago
Sammanfattning : Increasing habitat fragmentation and rapid global warming is changing the conditions for species populations and ecological communities around the world. This presents challenges for the maintenance of biodiversity and a dominant paradigm for conservation in fragmented habitats is given by island biogeography and metapopulation (or metacommunity) ecology. LÄS MER
2. Wood-inhabiting fungi of alder forests in north-central Scandinavia : 1, Aphyllophorales (Basidiomycetes). Taxonomy, ecology and distribution
Sammanfattning : Wood-inhabiting fungi were collected on different trees in 99 loca-' lities of alder woods, dominated by Alnus incana or occasionally A. glutinosa, in N-C Sweden and C Norway. Most of the localities are situated near the east coast of Sweden where the prevailing land elevation creates conditions suitable for colonization by alder. LÄS MER
3. Recruitment and understorey herb dynamics in deciduous and mixed coniferous forest
Sammanfattning : The distribution and abundance of plant species is determined by the ability to disperse, recruit and persist in a suitable habitat. Plant-animal interactions influence recruitment by reducing seeds and seedlings through predation and herbivory. LÄS MER
4. Phytoplankton in Swedish oligotrophic lakes, affected by acidification, metals and liming
Sammanfattning : Anthropogenic airborne acidification has seriously affected thousands of lakes in Sweden, an alarming fact which was first noticed in the early 1970s, when pH had decreased to values below 5, especially in areas poor in limestone such as the Swedish west coast. This development was critical to phytoplankton, the diversity of which being markedly reduced, and where the groups Cyanophyceae, Bacillariophyceae and Conjugatophyceae were totally eliminated. LÄS MER
5. Evolution of seed attributes, dispersal and population dynamics of plants,with special emphasis on fragmented habitats
Sammanfattning : Theory predicts that life history traits that reduce the impact of environmental variation will exhibit a pattern of negative covariation (trade-offs). In plants, such traits are seed size, spatial seed dispersal and seed dormancy which interact to reduce risk in a variable environment. LÄS MER
