We currently have only a rudimentary understanding of what controls the community composition of arbuscular mycorrhizal fungi (AMF), ubiquitous root symbionts. Traditionally, scientists thought that associations between plants and AMF were non-species specific, but recent work shows that both plants and AMF species have preferences for particular partners. How these preferences affect AMF community composition in mixed plant communities remains unclear. For my dissertation, I am working in the California coastal prairies of Marin County to compare the effects of plant hosts on the composition of the AMF community. I will examine how invasive plant monocultures can alter AMF assemblages, and I will test whether certain plants in the local neighborhood can exert disproportionately large influence on the AMF community of another plant host. Additionally, my research will describe how AMF assemblages can shift as new plant species and new species combinations are added to the system. Results from this research will illustrate how invasion-mediated shifts in the plant community can alter belowground communities, since a loss of diversity aboveground may be mirrored by a loss of diversity belowground. Investigations such as the one proposed here will help us understand the broad, ecosystem-level implications of these widespread plant invasions.
