IGN 13-4 - Invasion alters ecosystem response to drought via shorter growing seasons and lower carbon capture

Wednesday, August 9, 2017
C123, Oregon Convention Center
Elsa Cleland1, Ellen Esch1 and David Lipson2, (1)Ecology, Behavior & Evolution Section, University of California - San Diego, CA, (2)Department of Biology, San Diego State University, San Diego, CA
Invasive species can display greater phenological sensitivity to climate compared to native species, potentially influencing ecosystem responses to climatic changes such as drought. We manipulated rainfall on plots dominated by native shrubs or exotic annual plants, and measured canopy greenness as a proxy for photosynthetic carbon gain. Drought caused vegetation to senesce earlier where exotic species dominated, shortening the growing season and reducing potential ecosystem carbon gain more than in areas dominated by native vegetation. These results demonstrate that invasion can alter ecosystem responses to climate change, especially when native and invading species have differing phenological sensitivity to environmental cues.