Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. 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

  2. 2. The long-term decline of the grey-sided vole (Clethrionomys rufocanus) in boreal Sweden: importance of focal forest patch and matrix

    Författare :Pernilla Christensen; Birger Hörnfeldt; Rolf A. Ims; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; : Destructive sampling; high quality habitat; focal habitat; landscape; habitat fragmentation; threshold; clear-cut; patch size and quality; long-term time-series; Terrestrial ecology; Terrestisk ekologi;

    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

  3. 3. Hidden biodiversity in an alpine freshwater top predator : Existence, characteristics, and temporal dynamics of cryptic, sympatric brown trout populations

    Författare :Anastasia Andersson; Linda Laikre; Nils Ryman; Paulo Prodöhl; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; cryptic sympatry; population genetic structure; sympatric populations; intraspecific biodiversity; genetic monitoring; conservation genetics; trophic polymorphism; genetic connectivity; temporal stability; Salmo trutta; populationsgenetik; Population Genetics;

    Sammanfattning : Intraspecific genetic diversity is imperative to the survival of species in a changing environment, and it plays a vital role in ecosystem function. Since this type of diversity can be difficult to detect it is sometimes referred to as “hidden biodiversity”. LÄS MER

  4. 4. Grazing and the geographical range of seaweeds : The introduced Fucus evanescens and the newly described Fucus radicans

    Författare :Helena Forslund; Lena Kautsky; Ove Eriksson; Veijo Jormalainen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; non-indigenous species; phlorotannin; herbivore defense; ; Biology; Biologi; Marine ecology; Marin ekologi; Plant Ecology; växtekologi;

    Sammanfattning : Along the coast of temperate oceans brown algae of the genus Fucus form dense stands on rocky shores and are keystone species of the coastal ecosystem. These large seaweeds are perennial and function as substrate for many sessile marine organisms, provide shelter for fauna and juvenile fish, and are food source. A number of abiotic (e.g. LÄS MER