The BBVA Foundation Frontiers of Knowledge Award in Ecology and Conservation Biology goes, in this ninth edition, to Gene E. Likens and Marten Scheffer. Both have contributed in complementary ways to developing the theoretical underpinnings as well as understanding empirical patterns of gradual, abrupt and potentially irreversible ecosystem change in response to pollution and other ecological problems.
Gene Likens contributed the concept of integrated ecosystem science by developing methods to monitor and assess long-term trajectories of change. Early in his career, he studied long-term changes in nutrient cycling in forested watersheds, and assembled evidence that rain was becoming more acidic. This science was instrumental to develop effective policies to reduce the acid rain problem, and informed the U.S. Clean Air Act Amendments of 1990, with great impact on environmental law and clean-energy research.
One of the major causes of uncertainty in predicting environmental futures is the difficulty of knowing when ecosystems may shift abruptly into a new state. Marten Scheffer has provided elegant empirical examples of systems reaching these “tipping points” in his studies of how shallow lakes respond to nutrient pollution and nutrient regulations. His work demonstrated that cessation of pollutant inputs to lakes is often insufficient to restore their function and biodiversity, as ecosystem memory sets these lakes onto a new trajectory of change. Scheffer has applied this theory to a wider variety of environmental problems, like the consequences of the loss of large predators and overfishing on the future trajectory of aquatic ecosystem function and biodiversity. He has also developed theoretical approaches to identify ecosystems that are poised for catastrophic and potentially irreversible change.