Department of Botany and Plant Sciences
University of California Riverside
Traits & Trophic Interactions
Determining the factors that regulate plant abundance and composition has been a long-standing endeavor for ecologists. Traditionally, this issue has been addressed by examined with a “bottom-up” perspective and has focused primarily on the relative importance of environmental factors and plant-plant interactions in structuring communities. Increasingly, however, we know that soil biota and herbivores can also influence the recruitment into local plant communities and can be key to dictating the ultimate structure of the resident community. Our work examines how generalist herbivores influence recruitment and the ultimate composition of species and traits within local plant communities.
Big Little Rodents and Blooms and Busts
We our expanding our research efforts from the foothills of the Sierras to the annual grasslands of the Central Valley at the Carrizo Plain National Monument. These grasslands are gem within the state for a variety of reasons including they are home to several endangered species including the charismatic Giant Kangaroo Rat. GKR has a profound impact on this system as an ecosystem engineer. As part of our ongoing research here we are interested in how its impacts influence the spatial and temporal stability of these grasslands. Secondly, we are exploring how aridification of these grasslands can affect these plant-herbivore interactions to influence the adaptive capacity of this system. Lastly, we are working with the managing partners at the Monument to create a decision framework to help improve the conservation grazing efforts at the Monument.
How do small mammals influence community trait composition?
Despite our growing understanding of the importance of generalist consumers in affecting plant communities, top-down impacts are rarely included in trait-based studies of community assembly. There is great potential for generalist consumers to strongly influence the functional diversity of plant communities as granivorous rodents often prefer larger seeded species and herbivorous rodents often prefer seedlings of fast-growing, N-rich species. The goals of this proposed research are to: 1) investigate how individual traits of plant species influence the outcome of small mammal granivory and/or herbivory, 2) explore how responses to granivory/herbivory vary with varying strength of plant competitive interactions and 3) explore how these responses may vary between native and exotic species.