Gresty Catherine E A, Clare Elizabeth, Devey Dion S, Cowan Robyn S, Csiba Laszlo, Malakasi Panagiota, Lewis Owen T, Willis Katherine J
Department of Zoology University of Oxford Oxford UK.
School of Biological and Chemical Sciences Queen Mary University of London London UK.
Ecol Evol. 2018 Jul 7;8(15):7574-7587. doi: 10.1002/ece3.4234. eCollection 2018 Aug.
Floral foraging resources are valuable for pollinator conservation on farmland, and their provision is encouraged by agri-environment schemes in many countries. Across Europe, wildflower seed mixtures are widely sown on farmland to encourage pollinators, but the extent to which key pollinator groups such as solitary bees exploit and benefit from these resources is unclear. We used high-throughput sequencing of 164 pollen samples extracted from the brood cells of six common cavity-nesting solitary bee species (, , , , and ) which are widely distributed across the UK and Europe. We documented their pollen use across 19 farms in southern England, UK, revealing their forage plants and examining the structure of their pollen transport networks. Of the 32 plant species included currently in sown wildflower mixes, 15 were recorded as present within close foraging range of the bees on the study farms, but only L. was identified within the pollen samples. L. was the most commonly found of the 23 plant species identified in the pollen samples, suggesting that, in addition to providing a nesting resource for leafcutter bees, it may be an important forage plant for these species. Higher levels of connectance and nestedness were characteristic of pollen transport networks on farms with abundant floral resources, which may increase resilience to species loss. Our data suggest that plant species promoted currently by agri-environment schemes are not optimal for solitary bee foraging. If a diverse community of pollinators is to be supported on UK and European farmland, additional species such as should be encouraged to meet the foraging requirements of solitary bees.
花卉觅食资源对于农田传粉者的保护具有重要价值，许多国家的农业环境计划都鼓励提供此类资源。在欧洲，野花种子混合物被广泛播种在农田上以吸引传粉者，但诸如独居蜂等关键传粉者群体利用这些资源并从中受益的程度尚不清楚。我们对从六种常见的筑巢于洞穴的独居蜂（、、、、和）的育雏细胞中提取的164个花粉样本进行了高通量测序，这些独居蜂广泛分布于英国和欧洲。我们记录了它们在英国英格兰南部19个农场的花粉利用情况，揭示了它们的觅食植物，并研究了它们的花粉传播网络结构。在目前播种的野花混合物中包含的32种植物物种中，有15种被记录在研究农场中蜜蜂近距离觅食范围内，但在花粉样本中仅鉴定出了L.。L.是在花粉样本中鉴定出的23种植物物种中最常见的，这表明，除了为切叶蜂提供筑巢资源外，它可能是这些物种重要的觅食植物。在拥有丰富花卉资源的农场中，花粉传播网络具有较高的连通性和嵌套性特征，这可能会增加对物种损失的恢复力。我们的数据表明，目前农业环境计划所推广的植物物种并非独居蜂觅食的最佳选择。如果要在英国和欧洲的农田中支持多样化的传粉者群落，应该鼓励引入诸如等其他物种以满足独居蜂的觅食需求。
