PARENT SESSION
MP1 - Sustainable Development: Science, Adaptive Management & Ecosystem Restoration
Chair: Luoma, Sam1, 1 USGS, Menlo Park, CA
2:10 PM to 5:30 PM - Monday, 18 November 2002
Room Ballroom G-I
(256) Adaptive management of the Florida Everglades, mercury contamination, and development of land and water resources: Can restoration find a middle ground?
Krabbenhoft, David*,1, Orem, William2, Aiken, George3, Gilmour, Cynthia4, 1 U.S. Geological Survey, Middleton, WI, USA2 U.S. Geological Survey, Reston, Virginia, USA3 U.S. Geological Survey, Boulder, Colorado, USA4 Academy of Natural Sciences, St. Leonard, Maryland, USA
ABSTRACT- Current ecosystem restoration efforts of the Florida Everglades are one of the largest efforts if its kind, with estimated project costs ranging from 8 to 16 billion dollars. As with any large-scale restoration, the cost-benefit analysis of any mitigation plan will be highly scrutinized, especially when the ecosystem targeted for restoration is viewed as one of nature's "crown jewels". The USGS initiated the Aquatic Cycling of Mercury in the Everglades (ACME) project in 1995 to provide a fundamental understanding of the processes and controlling factors that lead to high levels of methylmercury in the food webs of the Everglades. At that time, scientists understood that wetlands were sites of high net production of methylmercury, but the precise reasons why were not well known. Through several years of detailed examinations, the ACME project revealed many new fundamental discoveries about controls of methylation, and many of these discoveries directly relate to restoration and resource development goals. Examples include: (1) the existence of a large sulfate source north of the Everglades (the Everglades Agricultural Area) that has a substantial controlling influence on the ecosystem scale distribution of methylmercury; (2) natural and man-influenced wetting and drying cycles that catalyze punctuated periods of elevated methylation; and, (3) water-treatment wetlands, constructed for the purposes of conditioning agricultural runoff before entering the Everglades, yielding high levels of methylmercury depending on antecedent soil chemistry and hydroperiod maintenance. In addition, plans for an extensive aquifer storage and recovery program to meet future water use needs have potential to exacerbate the methylmercury problem further. As scientific understanding of mercury methylation has evolved, a potential conflict with restoration targets has come to light, and has underscored the need for adaptive management plans based on sound understanding of the complexity inherent to this ecosystem and mercury cycling.
Key words: restoration, management, mercury