Linn Vassvik
Research Scientist
Authors
Linn Vassvik Anders Nielsen Michael P. D. Garratt Bjørn Arild Hatteland Joseph Chipperfield Erik Trond AschehougAbstract
Apples are dependent upon pollinators for the transfer of pollen between cultivars to ensure high quality fruit production. Agricultural intensification has reduced the availability of stable floral resources for wild bees, leading to widespread declines of important pollinators of apples. Managed honeybees are commonly used to supplement pollination services in apple orchards, but honeybees are less efficient pollinators compared to wild bees. We investigated whether increased flower abundance in the understory vegetation of apple orchards can increase pollinator activity to apple flowers. We compared bee visitation in five orchards in Eastern Norway: three unmowed orchards, and two mowed orchards. In unmowed orchards, dandelions ( Taraxacum spp.) dominated the understory vegetation. Bee observations were conducted on the understory vegetation and apple trees, via manual observations and time-lapse cameras. Wild bees preferentially visited apple flowers over dandelions, while honeybees did not differ in their visits to apple flowers and dandelion flowers. We also found that the abundance of dandelion flowers in the understory increased visits by wild bees to apple flowers. Taken together, this suggests that within orchard floral resources do not compete for pollinators but instead increase apple visitation and improve pollination success. Our results highlight the importance of managing apple orchards for wild bee populations and the potential short-term benefits of understory floral resources on apple production. Implications for insect conservation Our results show that understory vegetation should be left unmowed to increase pollination of apple flowers and provide pollinators with alternate floral resources before, during, and after apple flowering.
Abstract
ASO er Norges første nasjonale, arealrepresentative overvåking av semi-naturlig eng, en truet naturtype med stort artsmangfold. I perioden 2021–2025 ble 713 enger registrert over hele landet. Estimert areal av seminaturlig eng er 2 200–4 500 km² (0,7–1,5 % av Norges landareal), betydelig mer enn tidligere kartlagt. 40 % av engene er intakte, men majoriteten er ikke i bruk og i ferd med å gro igjen. Problemarter og fremmede arter utgjør viktige påvirkningfaktorer, og 32 % av engene har fremmedartsinnslag. Artsmangfoldet er størst i slåttemark og naturbeitemark, og 35 rødlistede arter ble funnet. Rapporten gir anbefalinger for videre overvåking, inkludert justering av metoder, bedre datalagring og overgang til NiN 3.0. ASO gir viktig kunnskap for forvaltning og bevaring av semi-naturlig eng og dens artsmangfold i Norge.
Authors
Linn Vassvik Bjørn Arild Hatteland Erik Trond Aschehoug Anders Nielsen Anne Mathilde KnudsenAbstract
Eple er Norges mest produserte frukt, likevel er de fleste eplene vi spiser importerte. Kan nye eplesorter og tilrettelegging for villbier øke produksjonen og derigjennom forbedre Norges selvforsyningsgrad?