Sökning: "bumble bees"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden bumble bees.
1. Species-isolating mechanisms in male bumble bees (Hymenoptera, Apidae)
Sammanfattning : .... LÄS MER
2. Biodiversity in Agricultural Landscapes: Landscape and Scale-Dependent Effects of Organic Farming
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
3. Ecological interactions in human modified landscapes : Landscape dependent remedies for the maintenance of biodiversity and ecosystem services
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
4. Ecology and management of crop pollination and pest control : insights from red clover seed production
Sammanfattning : The agricultural landscape has gone through large changes to meet increasing demands for food. This has led to major biodiversity declines, while effects on ecosystem services that support agricultural productivity, such as pollination and pest control, remain less studied. LÄS MER
5. Pollinators and Insect Pollination in Changing Agricultural Landscapes
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