CRB: The Role of Seed Limitation, Resource Competition, and Community Complementarity in Invasions and Restorations

This project would research the efficacy of one particular technique in the restoration of native perennial California grasslands. Invasions by exotic species are among the most serious threats to global biodiversity and restoration is a critical tool to mitigate losses. In California, 9.2 million ha of native perennial grassland has been invaded by exotic annual plants from the Mediterranean region with a concomitant loss of native plant biodiversity, and altered biogeochemical processes including increased nitrate leaching, altered fire regimes, and decreased carbon storage.

This research will utilize experiments that focus on the underlying ecological processes, particularly seed limitation and altered ecosystem processes, that may have facilitated and maintained the conversion of native habitat. The generality of the results will be determined by conducting experiments across a broad range of latitudes and habitats within California. The results may have broad application to many other settings where similar alteration of native habitats have occurred, providing an important tool to promote restoration efforts. Furthermore, the research sites employ up to 15 undergraduates students a year, and are visited by hundreds of school children and adults, providing an opportunity to educate people about important ecological changes and how to ameliorate them.