Local community assembly is often driven by a combination of abiotic filters and biotic interactions. Examining species’ functional traits may elucidate how abiotic factors and biotic interactions combine to filter species into different local communities. Moreover, using such an approach may aid our understanding of linkages between local taxonomic and functional diversity to broader community properties like ecosystem functioning. Here, we address the interaction of community assembly rules and functional trait diversity in a California pollination system on two adjacent soil types. Serpentine soils are strong drivers of native plant diversity and endemism in California’s coast ranges; however, little work has been done to date to explore the bottom-up effects of soil type on plant and pollinator community composition. I used a broad-scale field study to collect data on the diversity and abundance of flowering plants and their insect pollinators (e.g. bees, butterflies, and flies) across soil type and geography in northern California. By measuring taxonomic and functional diversity of plants and pollinators in each local community, I quantified the niche diversity of each locale.
Results/Conclusions
Preliminary results suggest that non-serpentine pollination communities are comparatively simple, often dominated by invasive plant species and fewer pollinator species, whereas serpentine sites generally have greater plant and pollinator richness and abundance. A total of 915 insect specimens were collected from eight field sites over the course of 50 hours of sampling during three months in 2017; 2018 field work repeats the previous year’s work.
Partial mantel tests, partial redundancy analysis, and linear modeling are ongoing to tease apart edaphic and geographic drivers of taxonomic and functional diversity patterns. Elucidating the underlying drivers of plant and pollinator functional diversity can provide insight into pollination community assembly processes and niche breadth and complementarity. Soil type may be a very strong driver of pollinator diversity, highlighting the importance of harsh soils and their plant communities for sustaining diverse native pollinator communities.