Features of agricultural landscapes that influence taxonomic and functional diversity of wild bees

Bee species diversity within agricultural landscapes responds positively to nearby natural habitats and lower cultivation in the surrounding landscape. Local habitats with diverse floral resources may also foster greater bee functional diversity. However, less is known about the interaction between local and landscape features and their impact bee functional diversity in heterogeneous agroecosystems. In this study, we evaluate how local and landscape vegetation influences the taxonomic and functional diversity of bee communities in avocado and lemon orchards in southern California. Specifically, we aim to (1) characterize species diversity, species abundance, and functional diversity of wild bees in these orchards, and (2) evaluate how local and landscape-scale vegetation and floral resources affect wild bee species diversity and functional diversity. To do this, we sampled insect communities using blue vane traps and pan traps at 16 orchards that vary in proximity to restored riparian habitats and presence of maintained hedgerow field margins. Our preliminary results indicate that local vegetation near orchards (e.g., hedgerows) positively impacts bee species richness, but this effect is dependent on the surrounding landscape composition. Additionally, local floral species richness increases bee species richness in avocado orchards and at orchards with vegetated margins. Finally, we found a difference in the community composition between crop type and in communities that are close versus distant to larger semi-natural vegetation. The results from this study will enhance our ability to develop effective conservation strategies to support wild bee populations and the crops they help produce.