A large body of research has emerged on how declining biodiversity affects the integrity of natural systems and their ability to provide for society. Much of this research has limited relevance to actual ecosystems and their conservation, however, because of experimental features that reduce realism. This project will bridge from experiment to application by examining the effects of realistic plant species losses thought to be driven by urban vehicular nitrogen deposition in California's unique serpentine grasslands. It will examine how species losses affect the resistance of this ecosystem to invasion by exotic species, its ability to support a diversity of animals, and its soil fertility and nutrient cycles.
This project will be the first of its kind to directly compare the consequences of random and realistic biodiversity losses. In so doing, it will help managers apply lessons from hundreds of existing studies based on random losses to real ecosystems experiencing very non-random species declines. It will also directly support management of the many serpentine grassland reserves in California by clarifying whether and how vehicle nitrogen emissions are contributing to the decline of this ecosystem. Finally, it will support career development for at least four aspiring scientists, from a junior professor to a talented young undergraduate to urban high school students, from underrepresented backgrounds.