Sökning: "bumblebee"

Visar resultat 6 - 10 av 13 avhandlingar innehållade ordet bumblebee.

1. 6. Effects of landscape context on populations of bumblebees

   Författare :Anna Persson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Apoidea; Bombus; Campanula; agriculture; land-use intensity; complexity; garden; grassland; field border; MFC; pollination; Factor Analysis;

   Sammanfattning : To investigate recent declines in bumblebee populations, I carried out landscape analyses, made field studies of bumblebees, flowering plants and pollination in an agricultural region in southernmost Sweden. Studies were carried out in landscapes of contrasting agricultural intensity and land-cover configuration; "simple" landscapes highly dominated by large crop fields, and "complex" with mixed farming, grasslands and smaller fields. LÄS MER

3. 7. Linear infrastructure habitats for the conservation of plants and pollinators - The value of road verges and power-line corridors for landscape-scale diversity and connectivity

   Författare :Juliana Dániel Ferreira; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The substantial reduction in the area of semi-natural grasslands due to the intensification of agriculture and silviculture has resulted in a dramatic decline of species that depend on these habitats. Simultaneously, the area of grassland habitats along infrastructure such as power lines and roads continues to increase and can even surpass the area of semi-natural grasslands of high nature value. LÄS MER

4. 8. Go with the flow : visually mediated flight control in bumblebees

   Författare :Nellie Linander; Funktionell zoologi; []
   Nyckelord :insect; vision; Bombus terrestris; flight control; optic flow; centring; flight speed; height; viewing angle; learning flight; Insect; vision; Bombus terrestris; flight control; optic flow; centring; flight speed; height; viewing angle; learning flight;

   Sammanfattning : Despite their small brains and tiny eyes, flying insects are capable of detecting and avoiding collisions with moving obstacles, and with remarkable precision they navigate through environments of different complexity. For this thesis, I have investigated how bumblebees use the pattern of apparent image motion that is generated in their eyes as they move through the world (known as optic flow), in order to control flight. LÄS MER

5. 9. Neural correlates of diverse navigational strategies

   Författare :Marcel Sayre; NanoLund: Centre for Nanoscience; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; central complex; connectome; path integration; bees; ants; neuroethology; neuroscience;

   Sammanfattning : Insects have evolved diverse and remarkable strategies for navigating in various ecologies all over the world. In particular, central place foragers, such as bees and ants, have become renowned for their fascinating navigational capabilities. At the heart of insect navigation lies a brain area known as the central complex (CX). LÄS MER

7. 10. Wild bees in agricultural landscapes: Modelling land use and climate effects across space and time

   Författare :Maria Blasi Romero; Centrum för miljö- och klimatvetenskap (CEC); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wild bees; Agricultural landscapes; climate change and agriculture; Phenology; Land-use; Model transferability; Ecological models; Pollination;

   Sammanfattning : Wild bees are declining in many parts of the world, which poses a risk for crop pollination and ecosystem health. Land use and climate change are two of the main drivers of the decline, and understanding the interactive effects of these two drivers and wild bees is very important to be able to develop proper responses and mitigate future negative effects. LÄS MER