Sökning: "beta diversity"

Visar resultat 1 - 5 av 45 avhandlingar innehållade orden beta diversity.

1. 1. Biodiversity patterns and the processes regulating them along elevation gradients in the Swedish mountains

   Författare :Johannes Måsviken; Love Dalén; Anne Bjorkman; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biodiversity; elevation gradients; spiders; insects; plants; latitude; altitude; alpha diversity; beta diversity; taxonomic diversity; phylogenetic diversity; functional diversity; Systematic Zoology; zoologisk systematik och evolutionsforskning;

   Sammanfattning : Biodiversity describes the total variation of life and includes the taxonomic, genetic, and phenotypic differences among organisms. Variations of biodiversity in space and time may be driven by ecological, evolutionary, or neutral processes. LÄS MER

3. 2. 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

4. 3. Plant Species Composition and Diversity in Cliff and Mountain Ecosystems

   Författare :Henrik Antonsson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cliff ecology; bryophytes; biodiversity; beta diversity; dispersal; facilitation; nurse plant; plant-plant interactions; Silene acaulis; stress;

   Sammanfattning : Ecosystems today are under increasing pressure from a rapidly changing climate, changes in land-use, habitat fragmentation and degradation and increasing anthropogenic disturbance. Studying drivers of biodiversity patterns is of increasing importance for understanding the dynamics of communities and their reactions and adaptation to changes in the future. LÄS MER

5. 4. Plant community assembly during succession from arable fields to semi-natural grassland

   Författare :Barbara Christine Schmid; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diversity; arable-to-grassland succession; space-for-time approach; land-use history; plant community assembly; grazing management; connectivity measures; dispersal vector; vascular plants; grassland specialist conservation;

   Sammanfattning : Large areas of grazed, species rich semi-natural grassland were lost in Europe during the last two centuries and as a consequence led to decreases in grassland specialist species. Therefore, today the “restoration” of grassland on previously arable fields is recommended for the protection of grassland specialists. LÄS MER

7. 5. Defining human adaptive immune gene diversity

   Författare :Sanjana Narang; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : The lymphocytes (B and T cells) of the adaptive immune system undergo variable (V), diversity (D), and junctional (J) gene recombination, resulting in highly diverse antigen receptor repertoires capable of recognizing a wide variety of invading pathogens. The B cell receptor (BCR) contains two identical heavy and light chains. LÄS MER