Wild bees encounter environmental microbes while foraging. While environmental context affects bee diversity, little is known about it how affects the wild bee microbiome. We used field surveys in 17 urban gardens to examine whether and how variation in local and landscape habitat features shapes the microbiome of the solitary Blue Orchard Bee, Osmia lignaria. We installed O. lignaria cocoons at each site, allowed bees to emerge and forage, then collected them. We measured local features of gardens using vegetation transects and landscape features with GIS. We found that in microbiome composition between bee individuals varied by environmental features such as natural habitat, floral resources, and bee species richness. We also found that environmental features were associated with the abundance of bacterial groups important for bee health, such as Lactobacillus. Our study highlights complex interactions between environment context, bee species diversity, and the bee-associated microbes.

野生蜜蜂在觅食时会遇到环境微生物。虽然环境影响蜜蜂的多样性，但对其如何影响野生蜜蜂微生物组知之甚少。我们在17个城市花园中进行了实地调查，以研究局部和景观生境特征的变化是否以及如何影响孤独的蓝色果园蜂Osmia lignaria的微生物组。我们安装了O. lignaria在每个地点收集茧，让蜜蜂出来觅食，然后收集它们。我们使用植被样带和GIS的景观特征测量了花园的局部特征。我们发现，蜜蜂个体之间的微生物组组成因环境特征（例如自然栖息地，花卉资源和蜜蜂种类丰富度）而异。我们还发现，环境特征与大量对蜜蜂健康重要的细菌群（如乳酸杆菌）有关。我们的研究突出了环境背景，蜜蜂物种多样性和与蜜蜂相关的微生物之间的复杂相互作用。