Sökning: "seed banks"
Visar resultat 1 - 5 av 11 avhandlingar innehållade orden seed banks.
1. Long-term studies of succession : Colonisation and seed banks
Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER
2. Seed banks, seed dispersal and regeneration processes in wetland areas
Sammanfattning : .... LÄS MER
3. Ecology and evolution of local adaptation in Arabidopsis thaliana
Sammanfattning : In this thesis, I investigate the ecological genetics of local adaptation in the annual herb Arabidopsis thaliana with the aim to identify key traits, agents of selection, and genomic regions contributing to adaptive differentiation. The thesis focuses on adaptive differentiation in timing of germination and seed dormancy between populations located close to the southern and northern range margins in Europe. LÄS MER
4. Submerged macrophytes in shallow eutrophic lakes - regulating factors and ecosystem effects
Sammanfattning : In this thesis I have studied factors that regulate submerged macrophyte abundance, morphology and distribution in shallow eutrophic lakes, and how submerged macrophytes may affect the ecosystem. Light attenuation through the water column (turbidity and water depth) is probably not the most important factor regulating the distribution of submerged vegetation in macrophyte dominated shallow eutrophic lakes, e. LÄS MER
5. Ecological rehabilitation of degraded hill slopes in southern Wello, Ethiopia
Sammanfattning : Clearing of vegetation has left large areas of southern Wello (Ethiopia) at a high risk ofland degradation. In this study, the causes, extent and consequences of land degradationproblems are reviewed. To see land cover changes, aerial photographs from 1958 and1986 were compared with the help of a GIS procedure. LÄS MER