Ronald Oremland Mark Marvin-DiPasquale 2005 spreadsheet http://sofia.usgs.gov/exchange/marvin-dipasquale/mmdindex.html The spreadsheet contains the data for 12 sites for sediment methylmercury degradation potential rate measurements High concentrations of methyl-mercury (CH3Hg+), a toxic substance to both animals and humans, recently have been measured in a number of top predators (including panthers and game fish) native to the Florida Everglades. The objective of this research was to provide ecosystem managers with CH3Hg+ degradation rate data from a number of study sites that represent a diversity of hydrologic and nutrient regimes common to the Everglades. The focus was on better understanding the microbial and geochemical controls regulating CH3Hg+ degradation. At the time of the study, little was known about the specific factors influencing this process in natural systems. 199606 199612 199704 199707 199801 199806 ground condition Complete None planned -81 -80 26.75 25 none biology geology chemistry methylmercury ISO 19115 Topic Category environment 007 Department of Commerce, 1995, Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative Divisions, Federal Information Processing Standard (FIPS) 10-4, Washington, DC, National Institute of Standards and Technology United States US U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of the United States, and associated areas (Federal Information Processing Standard 5-2): Washington, DC, NIST Florida FL Department of Commerce, 1990, Counties and Equivalent Entities of the United States, Its Possessions, and Associated Areas, FIPS 6-3, Washington, DC, National Institute of Standards and Technology Palm Beach County Miami-Dade County Monroe County Broward County USGS Geographic Names Information System Everglades National Park Loxahatchee National Wildlife Refuge none Central Everglades Greater Lake Okeechobee Everglades Nutrient Removal area WCA3 WCA2B Water Conservation Area 3 Water Conservation Area 2B none none All MeHg production and degradation rates were calculated as potential rates (i.e. based on the amount of radiolabel added) and not as in-situ rates. Mark Marvin-DiPasquale U.S. Geological Survey Project manager mailing address

345 Middlefield Road, Building 15, McKelvey Building

Menlo Park CA 94025 USA 650 329 4442 650 329-4463 mmarvin@usgs.gov http://sofia.usgs.gov/exchange/marvin-dipasquale/mmdsitemap.gif map showing location of sampling sites GIF MS Excel Marvin-DiPasquale, Mark C. Oremland, Ronald S. 1998 report Environmental Science and Technology v. 32, n. 17 Washington, DC American Chemical Society All users may view the abstract of this article. If you are a subscriber, you may view the article. If you are not a subscriber, you may purchase and download the PDF version of the article. http://pubs3.acs.org/acs/journals/doilookup?in_doi=10.1021/es971099l Marvin-DiPasquale, Mark C. Agee, Jennifer; McGowan, Chad; Oremland, Ronald S.; Thomas, Martha; Krabbenhoft, David; Gilmour, Cynthia C. 2000 report Environmental Science and Technology v. 34 , n. 23 Washington, DC American Chemical Society All users may view the abstract of this article. If you are a subscriber, you may view the article. If you are not a subscriber, you may purchase and download the PDF version of the article. http://pubs3.acs.org/acs/journals/doilookup?in_doi=10.1021/es0013125 Data were collected at a suite of sites between 1995 and 1998 in the Water Conservation Areas and Everglades National Park. Due to changes in methodology, only data collected since June 1996 is included in the dataset Not all sites have data for all dates Periodic field measurements of methylmercury (MeHg) degradation potential rates in sediment were conducted between 1995 and 1998, at a suite of study sites in the Water Conservation Areas and Everglades National Park. Intact sediment cores were collected by hand with polycarbonate core tubes (8 cm i.d. x 15-30 cm). The unconsolidated surface floc layer was treated as one discrete interval for June 1996, December 1996, and January 1998. Sediment below this zone was sectioned into 2 cm to 4 cm discrete depth intervals. Discrete depths were sampled for the whole core during April 1997, July 1997, and June 1998. For each interval, sediment from 3-6 cores was pooled for a homogenized composite sample. Subsamples (3 cc) were amended with radiolabeled 14C-MeHg (0.5 to 10 nCi) and incubated anoxically for 0.2 to 7 days at 18-25 deg C in 13 cc serum bottles. Incubations were arrested by adding 1 ml of 3 M NaOH. All incubations were initiated within 10 hours of sample collection, except during April 1997, which were initiated three days after collection. All site/depth discrete sample sets included n=3 replicates and one autoclave killed control. The gaseous 14 C endproducts (14 CH4 and 14 CO2) were assayed by a CH4 combustion/CO2 trapping assay as described in Marvin-DiPasquale and Oremland (1998) Environ. Sci. Tech. 32:2256-2263. 1998 Mark Marvin-DiPasquale U.S. Geological Survey Project manager mailing address

345 Middlefield Road, Building 15, McKelvey Building

Menlo Park CA 94025 USA 650 329 4442 650 329-4463 mmarvin@usgs.gov Water Conservation Areas and Everglades National Park Data collected for each site contain site id, date, sediment depth interval (cm), incubation time (days), 14C-MeHG injected (ng/cc wet sed), MeHg degradation first-order rate constant (k), and Me-Hg degradation potential rate (ng/cc set sed/d) USGS personnel Heather S.Henkel U.S. Geological Survey mailing address

600 Fourth St. South

St. Petersburg FL 33701 USA 727 803-8747 ext 3028 727 803-2030 hhenkel@usgs.gov Everglades Sediment Methylmercury Degradation Potential Rate Measurements The data have no explicit or implied guarantees. MS Excel unknown 0.041 http://sofia.usgs.gov/exchange/marvin-dipasquale/mmdindex.html Data may be downloaded from the SOFIA website. none 20080122 Heather Henkel U.S. Geological Survey mailing and physical address

600 Fourth Street South

St. Petersburg FL 33701 USA 727 803-8747 ext 3028 727 803-2030 sofia-metadata@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998