Sökning: "Grasslands"
Visar resultat 11 - 15 av 72 avhandlingar innehållade ordet Grasslands.
11. Land Use Change in Space and Time : implications for plant species conservation in semi-natural grasslands
Sammanfattning : Land use change has during the last century altered the traditional rural landscape in Sweden, resulting in a major decline in species diversity. Traditional small-scale farming, with a remarkably high small-scale species richness, has changed in favour of rationalized agriculture, and many semi-natural grasslands, i.e. LÄS MER
12. Restoration of plant and pollinator communities in fragmented grasslands
Sammanfattning : A large proportion of the former area of species-rich semi-natural grasslands has been lost due to agricultural intensification and abandonment. Remaining small and isolated grassland fragments are often imbedded in more or less intensively managed landscapes. LÄS MER
13. Semi-natural grasslands: landscape, history and plant species diversity
Sammanfattning : This thesis explores the impact of past and present landscape and habitat structure on present levels of vascular plant species diversity within fragmented semi-natural grasslands. Within the Jordtorp-area, a mosaic agricultural landscape on the island of Öland (Sweden), historical land-use changes and the development of semi-natural grasslands was characterized, over a time-period of almost 300 years, using historical maps, aerial photographs and a high-resolution imagery. LÄS MER
14. Regional and local variation in plant species richness
Sammanfattning : In this thesis, I examine the variation in plant species richness along gradients of productivity and disturbance in grasslands and forest habitats in southern Sweden, and I compare the documented patterns with theoretical predictions. Moreover, I evaluate the relative importance of habitat quality and habitat configuration for the occurrence of field layer species in deciduous forests. LÄS MER
15. Disturbance Effects on Plant and Mycorrhizal Communities in Sandy Grasslands
Sammanfattning : Many ecosystems have historically been disturbed, either naturally or as part of a cultural management. Due to loss of species as a result of too little disturbance, disturbance must be considered as a potential tool for conservation and restoration in various ecosystems. In this thesis work, disturbance effects on a grassland system were studied. LÄS MER