Sökning: "habitat continuity"
Visar resultat 1 - 5 av 14 avhandlingar innehållade orden habitat continuity.
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. Description of spatial and temporal distributions of epiphytic lichens
Sammanfattning : Lichens are, in most cases, sensitive to anthropogenic factors such as air pollution, global warming, forestry and fragmentation. Two studies are included in this thesis. The first is an evaluation of the importance of old oak for the rare epiphytic lichen Cliostomum corrugatum (Ach.) Fr. 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. Remote sensing of grassland communities : integrated effects of soil nutrients and habitat age
Sammanfattning : Semi-natural grasslands are characterized by high fine-scale plant species richness. The richest grassland communities, with many habitat-specialist species, are found in ancient grassland sites that have a long continuity of grazing management and low levels of soil nutrients. Grazed grasslands were widespread in the historical landscape. LÄS MER
5. Strengthening conservation through green infrastructure : linking protected areas, habitats and species
Sammanfattning : The green infrastructure (GI) concept was developed to mitigate habitat fragmentation. The European Union (EU) defines GI as “a strategically planned network of natural and semi-natural areas …designed and managed to deliver a wide range of ecosystem services and to improve connectivity of protected areas in order to promote multifunctional landscapes”. LÄS MER