caa a22 4500 467905282 CHVBK 20180406152832.0 cr unu---uuuuu 170328e20060101xx s 000 0 eng 10.1007/s10661-006-0767-4 doi (NATIONALLICENCE)springer-10.1007/s10661-006-0767-4 Extreme Spatial Variability and Unprecedented Methylmercury Concentrations Within a Constructed Wetland [Elektronische Daten] [D. Rumbold, L. Fink] We began monitoring concentrations of both total mercury (THg) and methylmercury (MeHg) in surface water at Stormwater Treatment Area-2 (STA) on July 20, 2000. This 2602 hectare STA was constructed with three independent marshes to remove phosphorus from agricultural runoff and reduce eutrophication in the northern Everglades. However, there was concern that in doing so, STA-2 might inadvertently worsen the existing mercury problem in the Everglades. Accordingly, operating permits stipulated that flow-through operation of these treatment cells could not begin until concentrations of THg and MeHg in the interior marsh were not significantly greater than corresponding concentrations in the supply canal. Cells 2 and 3 quickly met the start-up criteria in the fall of 2000. In contrast, Cell 1 exhibited anomalously high MeHg concentrations in the fall of 2000 and 2001, and the summer of 2002. During the last such event, water-column concentrations in Cell 1 reached 32 ng THg/L and an unprecedented 20 ng MeHg/L. Tissue Hg in resident fishes reached levels as high as 430 ng/g in mosquitofish, Gambusia holbrooki, 930 ng/g in sunfish, Lepomis spp., and 2000 ng/g in largemouth bass, Micropterus salmoides. Guided by results from the monitoring program, flow rate and water depth were managed as a means to alter sulfur biogeochemistry and, thereby, reduce in situ mercury methylation. This adaptive management strategy likely played a role in the decline in water-column concentrations of THg and MeHg in Cell 1 by late 2002 and the subsequent declines in tissue Hg levels in resident fishes. Cell 1 finally met formal start-up criteria on November 26, 2002. Springer Science + Business Media, Inc., 2006 bioaccumulation nationallicence constructed wetland nationallicence mercury nationallicence methylmercury nationallicence Rumbold D. South Florida Water Management District, West Palm Beach, Florida, U.S.A. aut Fink L. South Florida Water Management District, West Palm Beach, Florida, U.S.A. aut Environmental Monitoring and Assessment Kluwer Academic Publishers 112/1-3(2006-01-01), 115-135 0167-6369 112:1-3<115 2006 112 10661 https://doi.org/10.1007/s10661-006-0767-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10661-006-0767-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rumbold D. South Florida Water Management District, West Palm Beach, Florida, U.S.A aut NATIONALLICENCE 700 1- Fink L. South Florida Water Management District, West Palm Beach, Florida, U.S.A aut NATIONALLICENCE 773 0- Environmental Monitoring and Assessment Kluwer Academic Publishers 112/1-3(2006-01-01), 115-135 0167-6369 112:1-3<115 2006 112 10661 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer