Avancerad sökning
Visar resultat 1 - 5 av 185 avhandlingar som matchar ovanstående sökkriterier.
1. Plant species diversity in semi-natural grasslands. Effects of scale, landscape structure and habitat history
Sammanfattning : The thesis examines the impact of present and past landscape structure, habitat history and management on different aspects of present-day plant species diversity in fragmented semi-natural grasslands in Sweden and in Estonia. Species diversity was significantly associated with present and/or past grassland connectivity in the majority of the studies in the thesis. LÄS MER
2. Age-class interactions in Atlantic salmon and brown trout: Effects on habitat use and performance
Sammanfattning : This thesis investigates the underlying mechanisms and the density-regulatory effects of age-class interactions, using juvenile Atlantic salmon (Salmo salar L.) and brown trout (Salmo trutta L.) as study species. LÄS MER
3. 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
4. The long-term decline of the grey-sided vole (Clethrionomys rufocanus) in boreal Sweden: importance of focal forest patch and matrix
Sammanfattning : There has been a long-term decline in number of cyclic vole populations in boreal Sweden since the 1970s. Several hypotheses have been suggested to explain this decline. Commonly for C. glareolus, C. LÄS MER
5. Contested Landscapes : social-ecological interactions between forestry and reindeer husbandry
Sammanfattning : Throughout northern Fennoscandia, reindeer husbandry is a central part in the cultural heritage of the Sámi people. In its history, Sámi culture and reindeer husbandry have undergone significant adaptations to environmental, social and political challenges. LÄS MER