Friday, May 5, 2017
10:30am – 12:00 pm
Building 66 Auditorium
Lawrence Berkeley National Laboratory
Host: Nick Bouskill
About the Presenter: Dr. Paolo D’Odorico
Paolo D’Odorico has just joined UC Berkeley as a Professor of Hydrology in the Environmental Science Policy and Management Department. His research focuses on the role of hydrological processes in the functioning of terrestrial ecosystems and societies. Starting from analyses of mechanisms underlying the coupling between hydrological processes and the biota, his work has contributed to the emergence of the field of ecohydrology. Through field observations and modeling studies he is studying new mechanisms of desertification and factors contributing to ecosystem resilience at the desert margins. His work has highlighted the effect of positive feedbacks between vegetation and resource (e.g., nutrients, water, light, or energy) availability on the resilience of dry tropical forests, freshwater wetlands, desert grasslands, mangrove swamps, and seagrass meadows. His research has also shown how environmental variability may increase the complexity of ecosystem dynamics by inducing new bifurcations, pattern formation, and enhancing ecosystem resilience. He is currently investigating the global patterns of virtual water trade and international land investments and their impacts on water equity, societal resilience, and food security.
Drylands are undergoing changes in vegetation cover and plant community composition in response to shifts in climate conditions and land use dynamics. Changes in vegetation cover and composition can alter the fire regime and the surface energy balance with important potential feedbacks on hydroclimatic conditions. To date, some of the drivers and impacts of shifts in dryland vegetation remain poorly understood. Here I consider some major vegetation changes that are occurring in arid and semiarid landscapes worldwide, including woody plant encroachment, exotic grass invasions, soil cover loss, and increased CAM plant dominance. I evaluate their impact on fire frequency, rainfall regime, or exposure to low temperatures, and investigate their feedbacks on vegetation dynamics. More specifically, I evaluate possible feedbacks between fire and precipitation, discuss the impact of fire on savanna-forest transitions, and investigate the drivers of other major shifts in dryland vegetation in the context of global environmental change and land use patterns.