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Visar resultat 1 - 5 av 7 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Pollinators and Insect Pollination in Changing Agricultural Landscapes

   Författare :Lina Herbertsson; Miljövetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pollinators; pollination; agri-environment schemes; beekeeping; oilseed rape; sown flower strips; agri-environment measures;

   Sammanfattning : Agricultural intensification and associated loss of semi-natural grasslands, has resulted in reduced landscape heterogeneity. A concomitant loss of forage and nest sites for pollinating insects has driven declines across several pollinator taxa. LÄS MER

3. 2. Biodiversity in Agricultural Landscapes: Landscape and Scale-Dependent Effects of Organic Farming

   Författare :Maj Rundlöf; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Djurekologi; Natural science; Naturvetenskap; Ekologi; Animal ecology; plants; spatial scales; species richness; Ecology; landscape ecology; agri-environment schemes; farming practice; conservation; butterflies; bumble bees;

   Sammanfattning : Declines in the distribution and abundance of many farmland species during recent decades have been attributed to agricultural intensification. Agri-environment schemes are commonly used in Europe to reduce this loss of farmland biodiversity, but their effectiveness may depend on several external factors. LÄS MER

4. 3. Ecological interactions in human modified landscapes : Landscape dependent remedies for the maintenance of biodiversity and ecosystem services

   Författare :Arvid Bolin; Biodiversitet; []
   Nyckelord :Central place foraging; Agriculture; Competition; Ecosystem service; Species coexistence; bumble bees; landscape ecology; Biodiversity; Agri-environment scheme; Central place foraging; jordbruk; konkurrens; landskaps ekologi; humlor; bin;

   Sammanfattning : Modern agricultural practices have led to an intensification of the agricultural landscape which has negatively affected both biodiversity and the ecosystem services it provides. In my thesis I have used ecological theory of optimal foraging to try and explain how landscape structure, landscape composition and agricultural management can explain the loss of biodiversity and how remedies can efficiently be implemented. LÄS MER

5. 4. Small biotopes in agricultural landscapes: importance for vascular plants and effects of management

   Författare :Therese Irminger Street; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Small biotopes; incidental habitat; vascular plants; woody vegetation; grassland species; resource provisioning; species richness; habitat specificity; non-crop habitat; landscape complexity; heterogeneity; local management; agri-environment scheme;

   Sammanfattning : As a consequence of agricultural intensification, large areas of non-crop habitat have been lost and farmland biodiversity has declined. Previous studies have shown that the extent of non-crop habitat influences farmland biodiversity, but the relative importance of different habitat types is less well known and the contribution of small incidental habitats to landscape-scale species richness is not fully understood. LÄS MER

7. 5. Biodiversity and biological control : effects of agricultural intensity at the farm and landscape scale

   Författare :Camilla Winqvist; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Agricultural intensity on the local field or farm scale and on the regional landscape scale affects the organisms utilizing the arable landscape, and may affect ecosystem services and functions. This thesis examines how plants, birds, community composition of ground beetles, and biological control of cereal aphids are affected by local agricultural intensity, organic farming and the surrounding landscape in Sweden and across Europe. LÄS MER