Sökning: "species composition"

Visar resultat 16 - 20 av 706 avhandlingar innehållade orden species composition.

1. 16. The impact of forest on pest damage, pollinators and pollination services in an Ethiopian agricultural landscape

   Författare :Ulrika Samnegård; Kristoffer Hylander; Peter Hambäck; Sileshi Nemomissa; Jaboury Ghazoul; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; agroforestry; Apoidea; Coffea arabica; crop pests; Ethiopia; forest cover; landscape ecology; moist afromontane forests; pollination; species composition; tropical agriculture; Plant Ecology; växtekologi;

   Sammanfattning : The distribution of wild biodiversity in agroecosystems affect crop performance and yield in various ways. In this thesis I have studied the impact of wild biodiversity, in terms of trees and forest structures, on crop pests, pollinators and the pollination services provided in a heterogeneous landscape in southwestern Ethiopia. LÄS MER

3. 17. 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

4. 18. 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. 19. Ecosystem response to dam removal

   Författare :Anna G.C. Lejon; Christer Nilsson; Birgitta Malm Renöfält; Emily Stanley; Umeå universitet; []
   Nyckelord :dam removal; macroinvertebrates; plant species; plant succession; restoration; riparian zone; sediment deposition; species richness; Sweden; biology; biologi; ekologisk botanik; Ecological Botany; hydrologi; Hydrology;

   Sammanfattning : This thesis aims to improve our understanding of how riverine ecosystems respond to dam removal. Riverine and particularly riparian ecosystems are among the most variable and important features of all landscapes. LÄS MER

7. 20. Effects of morphometric isolation and vegetation on the macroinvertebrate community in shallow Baltic Sea land-uplift bays

   Författare :Joakim Hansen; Lena Kautsky; Erik Bonsdorff; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lagoons; macrofauna; macrophytes; hydrophytes; charophytes; ecological succession; structural complexity; habitat complexity; habitat selection; species composition; biodiversity; stable isotopes; food web; Terrestrial; freshwater and marine ecology; Terrestrisk; limnisk och marin ekologi; Plant Ecology; växtekologi;

   Sammanfattning : Shallow sheltered Baltic Sea bays are ecologically important habitats that harbour a unique vegetation community and constitute vital reproduction areas for many coastal fish species. Knowledge about the invertebrate community in these bays is, however, limited. LÄS MER