[PAST EVENT] Delineating marine ecosystem perturbation and recovery

December 6, 2013
10:30am - 11:30am
VIMS - Watermen's Hall, McHugh Auditorium
1375 Greate Road
Gloucester Point, VA 23062Map this location
Please note that this lecture has been postponed to Friday, December 6th at 10:30 am due to travel delays

Presenter: Dr. Jason Link, Senior Scientist with Ecosystem Management at NOAA

Seminar from 10:30 am to 11:30 am in McHugh Auditorium

Reception at 11:30 am in Watermen’s Hall Lobby

In 2012, NOAA named Jason Link, Ph.D., as its first-ever Senior Scientist for Ecosystem Management. In this new role, Dr. Link will be the agency's senior-most authority on ecosystem science, conducting research and coordinating activities of NOAA Fisheries' science support for effective ecosystem-based management. His priorities will be to lead approaches and models to support development of ecosystem-based management plans throughout the agency. A key element of Link's work will be the development of the tools and approaches that will allow us to deal with the impacts of climate change on our marine trust species.

Marine ecosystems provide billions of dollars of ecosystem services to the global community, from nutrient cycling to food production to recreation, cultural inspiration and identity. Human activities of many forms - eutrophication, habitat modification, toxic deposition, oil spills, overfishing, hypoxia, dredging, dumping, invasive species, and now acidification and climate change - can put significant pressure on these ecosystems via the direct or combined effects of these pressures. The desire to avoid undesirable alteration of ecosystem structure and functioning is manifest in the efforts to implement ecosystem-based management of marine ecosystems for sustainable use. Until now there has been no tested theory to predict how marine ecosystems respond to this suite of perturbations, nor any ability to determine when a marine ecosystem is perturbed beyond what is acceptable (or, conversely, recovered). Here we develop a new cumulative trophic theory for marine ecosystems, and from it two patterns have emerged. First, plots of cumulative biomass and trophic level result in sigmoidal curves showing how biomass builds up in marine ecosystems with regular inflection points. Second, plots of cumulative production and cumulative biomass curves consistently result in “hockey stick” patterns, showing a threshold level of ecosystem productivity. Simulations and data from over 130 ecosystems around the globe confirm that both of these patterns are robust to a wide range of data across all major marine ecosystem and perturbation types. Furthermore, the theory allows for the prediction of the magnitude and direction of impacts across a broad range of perturbations. Our results have clear application for setting reference thresholds against which marine ecosystem perturbation, or recovery, can be judged. These results not only better elucidate how marine ecosystems function, they show promise as operational tools for managing the world's ocean ecosystems.

[[seitz, Rochelle Seitz]] at 804-684-7698