Sökning: "indicator species"

Visar resultat 1 - 5 av 58 avhandlingar innehållade orden indicator species.

1. 1. 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

3. 2. Plant colonization of oak plantations - the interactive effects of local environment and land-use history

   Författare :Karin Valtinat; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nitrogen mineralization; Phosphorus; Plant ecology; Växtekologi; Soil acidity; Seed sowing; Dispersal limitation; Species diversity; Indicator species analysis; Functional groups; Succession; Understory vegetation; Land-use history; Temperate forest;

   Sammanfattning : In Europe, only small fragments of deciduous woodlands remain intact and species dependent on this ecosystem have declined. In southern Sweden, a shifting trend during the 20th century, with more afforestations on former arable land, resulted in new oak stands. These new stand are either on former arable fields or on continuously forested land. LÄS MER

4. 3. Nest-site attendance and foraging ecology of the Northern Fulmar (Fulmarus glacialis) on the Faroe Islands. Is the Northern Fulmar a useful indicator of ecosystem productivity and pollution?

   Författare :Johannis Danielsen; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nest-site attendance; foraging ecology; indicator species; Fulmar; Fulmarus glacialis; nocturnal activity; ecosystem productivity; pollution; mesopelagic fish;

   Sammanfattning : The Northern Fulmar (Fulmarus glacialis) is one of the most abundant seabirds in the Northern Hemisphere and the most abundant seabird on the Faroe Islands. Except from a few sporadic observations up until the 1950´s no study has focused on this species on the Faroe Islands. LÄS MER

5. 4. 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. 5. Network Based Tools and Indicators for Landscape Ecological Assessments, Planning, and Design

   Författare :Andreas Zetterberg; Berit Balfors; Ulla Mörtberg; Jan Bengtsson; KTH; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Least-cost modeling; Functional connectivity; Environmental planning tool; Resilience; Spatial redundancy; Ecological integrity; Landscape Ecology; Graph Theory; Ecological Network Graphs; Biodiversity; Conservation Biology; Urban Planning; Regional Planning; EIA; SEA; Environmental Assessment; Ecological Indicator; Impact prediction; Habitat suitability; Species distribution; Urban ecology; GIS; Urbanization; Miljöbedömningsverktyg; Landskapsplanering; Resiliens; Ekologisk integritet; Landskapsekologi; Grafteori; Ekologiska nätverk; Biologisk mångfald; Bevarandebiologi; Urban planering; Regional planering; MKB; SMB; Miljöbedömning; Ekologisk indikator; Konsekvensbedömning; Habitatmodellering; GIS; Urbanisering; Nature conservation and landscape management; Natur- och landskapsvård; Environmental engineering; Miljöteknik; Terrestrial ecology; Terrestisk ekologi;

   Sammanfattning : Land use change constitutes a primary driving force in shaping social-ecological systems world wide, and its effects reach far beyond the directly impacted areas. Graph based landscape ecological tools have become established as a promising way to efficiently explore and analyze the complex, spatial systems dynamics of ecological networks in physical landscapes. LÄS MER