Sökning: "species richness"

Visar resultat 6 - 10 av 172 avhandlingar innehållade orden species richness.

  1. 6. Small remnant habitats : Important structures in fragmented landscapes

    Författare :Jessica Lindgren; Sara Cousins; Regina Lindborg; Adam Kimberley; Ove Eriksson; Hans Henrik Bruun; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Alpha-diversity; Beta-diversity; Biological pest control; Canopy cover; Connectivity; Ecosystem function; Fleshy fruits; Forest edge; Forest management; Forest specialist species; Fragmentation; Functional diversity; Gamma-diversity; Grassland specialist species; Green infrastructure; Habitat amount hypothesis; Island biogeography; Midfield islets; Plant diversity; Plant-pollinator interaction; Pollination; Remnant habitat; Seed predation; Small habitats; Species richness; Structural heterogeneity; Physical Geography; naturgeografi;

    Sammanfattning : The world-wide intensification of agriculture has led to a decline in species richness due to land use change, isolation, and fragmentation of natural and semi-natural habitats in agricultural and forestry landscapes. As a consequence, there is a current landscape management focus on the importance of green infrastructure to mitigate biodiversity decline and preserve ecosystem functions e. LÄS MER

  3. 7. Biodiversity and Species Extinctions in Model Food Webs

    Författare :Charlotte Borrvall; Bo Ebenman; Owen Petchey; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biodiversity; food webs; redundancy; relaxation time; stability; stochasticity; species deletion; species extinction; Biology; Biologi;

    Sammanfattning : Many of the earth’s ecosystems are experiencing large species losses due to human impacts such as habitat destruction and fragmentation, climate change, species invasions, pollution, and overfishing. Due to the complex interactions between species in food webs the extinction of one species could lead to a cascade of further extinctions and hence cause dramatic changes in species composition and ecosystem processes. LÄS MER

  4. 8. Species Richness Patterns and Community Structure of Wood-Living Basidiomycetes (Agaricomycotina) in Nordic Spruce Forests

    Författare :Thomas Appelqvist; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wood-living basidiomycetes; species richness; lignin remnants; old-growth microhabitats; stand continuity; environmental continuity; community pattern; fungal guilds;

    Sammanfattning : .... LÄS MER

  5. 9. Regional and local variation in plant species richness

    Författare :Cecilia Dupré; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; coastal meadows; deciduous forests; dry grasslands; grazing; habitat configuration; habitat quality; hump-shaped curve; life history traits; regional species pool; soil factors; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; ekologisk botanik; Ecological Botany;

    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

  7. 10. Grassland restoration : Connectivity, plant community change and cows

    Författare :Rozália E. Kapás; Sara Cousins; Adam Kimberley; Lars A. Brudvig; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; biodiversity; colonization; connectivity; dispersal; distance to species pool; diversity; grassland restoration; grassland specialist species; grazing livestock; habitat availability; plant community composition; restoration; semi-natural grassland; species richness; naturgeografi; Physical Geography;

    Sammanfattning : The ecological significance of semi-natural grasslands is high because these habitats provide a home for a diverse flora and fauna and support a range of associated ecosystem services. Due to large-scale land-use changes the extent of grassland habitat has declined. LÄS MER