Sökning: "landscape ecology"

Visar resultat 16 - 20 av 231 avhandlingar innehållade orden landscape ecology.

1. 16. Forest edge development : management and design of forest edges in infrastructure and urban environments

   Författare :Björn Wiström; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

   Sammanfattning : This thesis investigates design guidelines and management systems for the development of stationary forest edges with a graded profile in infrastructure and urban environments. The spatial restriction for the edge to move forward caused by human land use counteracts the natural dynamics and development patterns of graded forest edges. LÄS MER

3. 17. Biotope and biodiversity mapping in forest and urban green space : methodological review and developments

   Författare :Tian Gao; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Forests play an important role in providing ecosystem services that support the ecological integrity of an area and also supply social benefits for humans. Many of the essential ecological and social benefits derived from forest are underpinned by its biodiversity. LÄS MER

4. 18. Distribution Patterns and Metapopulation Dynamics of Epiphytic Mosses and Lichens

   Författare :Tord Snäll; Håkan Rydin; Johan Ehrlén; Christine Ray; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; plant; metapopulation; model; parameterization; connectivity; dispersal; colonization; extinction; epiphytic; bryophyte; lichen; boreal; fragmentation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : This thesis examines the relative importance of local conditions, dispersal and dynamics of the trees on epiphyte distribution patterns and colonization-extinction dynamics. Study species are the mosses Orthotrichum speciosum and O. obtusifolium, and the red-listed Neckera pennata. LÄS MER

5. 19. Plants go with the flow : predicting spatial distribution of plant species in the boreal forest

   Författare :Ursula Zinko; Christer Nilsson; Håkan Rydin; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; boreal forest; vascular plant; species richness; wetness index; soil pH; bryophyte; lichen; substrate; stand age; plot size; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : The main objectives of this thesis are to study if a topographic wetness index (TWI) could be used as a tool for predicting the spatial distribution of vascular plant species richness in the boreal forest as well as to study congruence in species richness between vascular plants, liverworts, mosses and lichens. A wetness index ln(a/tanβ) based on topography was used to assign a specific TWI-value to every 20 x 20m grid in two 25 km2 boreal forest landscapes (differing in average soil pH) in northern Sweden. LÄS MER

7. 20. Biodiversity in fragmented boreal forests : assessing the past, the present and the future

   Författare :Håkan Berglund; Bengt Gunnar Jonsson; Jari Kouki; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; bryophytes; CWD; edge effects; fragmentation; fungi; habitat destruction; historical records; indicator; lichens; regression; species-area relationship; value pyramids; woody debris; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : The aims of this thesis are to (1) analyze the predictability (indicators) of plant and fungal species diversity in old-growth forests, and (2) assess the history and biodiversity of woodland key habitats (WKHs) and their potential to maintain species diversity in fragmented boreal forest landscapes. Predictability was explored in Granlandet nature reserve, an unexploited landscape composed of discrete old-growth Picea forest patches of varying size isolated by wetland, reflecting conditions of insular biota at stochastic equilibrium. LÄS MER