《Keep trees for bees: Pollen collection by Osmia bicornis along the urbanization gradient》

打印
作者
Aleksandra Splitt;Piotr Skórka;Aneta Strachecka;Mikołaj Borański;Dariusz Teper
来源
URBAN FORESTRY & URBAN GREENING,Vol.64,Issue1,Article 127250
语言
英文
关键字
Osmia rufa;Pollinators;Pollen-harvesting;Pollinivory larvae;Pollen analysis;Solitary bees
作者单位
Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland;The National Institute of Horticultural Research, Apiculture Division in Puławy, ul. Konstytucji 3 Maja1/3, 96-100 Skierniewice, Poland;Department of Zoology and Animal Ecology, Faculty of Environmental Biology, University of Life Sciences in Lublin, 20-950, Lublin, Poland;Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland;The National Institute of Horticultural Research, Apiculture Division in Puławy, ul. Konstytucji 3 Maja1/3, 96-100 Skierniewice, Poland;Department of Zoology and Animal Ecology, Faculty of Environmental Biology, University of Life Sciences in Lublin, 20-950, Lublin, Poland
摘要
Development of urban agglomerations and the intensification of agriculture profoundly affect bees’ food resources, hence ecosystem services such as pollination. A solitary bee, Osmia bicornis (syn. O. rufa), is an effective springtime pollinator of crops, decorative and wild plants. However, it is largely unknown if this species is conservative or plastic in pollen collection in different environments. New breedings of O. bicornis were established in localizations qualified as urban (90 % of built-up infrastructure), suburban (55–65 %), and rural (up to 20 %). From each nest randomly chosen samples of unused pollen provisions were collected and analysed. Moreover, literature databases of food composition of O. bicornis was compiled to show overall tendencies in the choice of plant type, habitat, as well as pollen coating and size. Our field study showed that in the less human-modified environment O. bicornis collected higher diversity of pollen types to build its provision, compared to more urban areas (Simpson diversity index was 3.7 in rural, 2.8 in suburban and 2.2 in urban sites). Literature review showed that bees repeatedly collected pollen from commonly available trees like oaks, maples, horse chestnut and elms. Field data also revealed that the use of tree pollen was especially common in urban sites while bees from suburban and rural sites included pollen of herbaceous plants and shrubs. Neither the shape nor the size of the pollen mattered to bee foraging choices. However, bees frequently used pollen dispersed by wind in urban sites. The main conclusion is that polylectic bees opportunistically collect pollen of plants present in the environment and number of plant taxa may be limiting factor for studied bees. The welfare of O. bicornis requires planting trees such as oaks, willows, maples, and representatives from Rosaceae family, and it is especially advisable in urban sites where herbaceous flowering plants are less common than in urban and suburban areas. Hence, keeping even singular trees may complement the bee food base in urbanized areas.