Tuesday, August 4, 2009: 8:00 AM-11:30 AM
Blrm A, Albuquerque Convention Center
Steve Carpenter, University of Wisconsin
Michael L. Pace, University of Virginia; and
Debra P.C. Peters, USDA Agricultural Research Service
Michael L. Pace, University of Virginia
Surging interest in ecological regime shifts, or massive changes in ecological systems, has expanded the scope of research on indicators. Indicators are important for anticipating, detecting and quantifying regime shifts. Some regime shifts, such as desertification, eutrophication, fisheries declines, or rangeland degradation, have important human consequences. Thus there is interest in leading indicators of incipient regime shifts that could be used to trigger management interventions to prevent degradation of ecosystem services. Current research in a wide variety of ecosystems is rapidly expanding our knowledge of indicators of regime shifts. Examples include studies of ecosystem-specific indicators of change using long-term data, statistical innovations for analysis of time series and spatially-structured ecosystems, and theoretical insights about observable characteristics of ecosystems undergoing regime shifts. For this session, we invited and coordinated a set of talks designed to expose, compare and contrast the diversity of data, theories and points of view about indicators of ecosystem regime shifts. The speakers include two leading theorists, as well as field scientists representing a range of perspectives and ecosystem types. Marten Scheffer will discuss his work on critical transitions in relation to leading indicators of a wide range of shifts in ecosystems, climate, finance and physiology. Max Rietkerk will discuss spatial pattern transitions and the implications of this crucial theoretical area for the science of leading indicators. Deb Peters will discuss patterns emerging from synthesis of extensive long-term data sets from ecosystems subject to regime shifts. Paolo d’Orico will address regime shifts in ecohydrology and vegetation of desert grasslands. Craig Allen will present a 300 year time series study of repeated regime shifts in a dynamic ecotone. Brad de Young will explore new findings about indicators of massive change in marine ecosystems. We have also left two open slots for papers that are offered during the general submission process to the ESA meeting. Steve Carpenter, the last speaker, will attempt to sum up the session. He will comment particularly on questions of statistical inference from ecological time series, experimental opportunities for evaluating indicators, and policy implications of leading indicators.