Project Summary Sheet

Project Title: Geochemical Monitoring of Restoration Progress

Project Start Date: October 1, 1999 Project End Date: September 30, 2004

Web Sites: SOFIA

Location (Subregions, Counties, Park or Refuge): Florida Bay, Everglades National Park

Funding Source: USGS's Greater Everglades Science Initiative (PBS)

Principal Investigator(s): Kimberly Yates

Project Personnel: Robert Halley, Nate Smiley, Chris Dufore, Iuri Herzfeld, Phillip Thompson

Supporting Organizations: Florida Marine Research Institute, Everglades National Park

Associated / Linked Projects: Historical Changes in Salinity, Water Quality and Vegetation in Biscayne Bay: Lynn Wingard

Overview & Objective(s): This project began in FY2000, and monitors changes in critical biogeochemical processes and water quality in Florida Bay as South Florida restoration proceeds. Project objectives include 1) productivity monitoring to assess restoration progress and its effect on critical environmental processes in the Bay, 2) performing Bay-wide, geochemical surveys bimonthly (salinity, pH, dissolved oxygen, total carbon and air:sea CO₂ gas flux) to measure changes in these parameters during implementation of restoration, and to identify sustained water quality changes that may result in ecosystem stress, and 3) comparison of results from productivity monitoring efforts to historical cycles of salinity change, carbonate sediment accumulation, and distribution patterns of subaquatic vegetation and indicator species to help identify when restoration has been accomplished. Each of these objectives defines each of three corresponding project tasks.

Status: FY2000 efforts focused on measuring current seasonal rates of productivity (including carbonate sediment production, photosynthesis and respiration) in Florida Bay to establish baselines for these parameters from which to monitor restoration progress. Productivity and bimonthly geochemical monitoring was continued through FY2001, 2002 and 2003. Objective (and task) 3 was begun in 2003 focusing on comparison of results from productivity monitoring efforts to historical cycles of carbonate sediment accumulation. All field activities for this 5-year project are now complete. It is anticipated that only objective (and task) 3, and general synthesis of project information will continue during FY04.

Recent & Planned Products: (¹Completed during FY03, ²Anticipated completion during FY04)

¹Yates, K.K. and Halley, R.B. 2003. Measuring coral reef community metabolism using new benthic chamber technology. Coral Reefs, vol. 22, issue 3.
¹Yates, K.K. et al. 2003. Surface water geochemical surveys in Florida Bay. Florida Bay Program and Abstracts, Joint Conference on the Science and Restoration of the Greater Everglades and Florida Bay Ecosystem, April 13-18, Palm Harbor.
¹Yates, K.K. et al. 2003. Surface water geochemical surveys in Florida Bay. U.S.G.S. Greater Everglades Science Program: 2002 Biennial report, USGS Open-file report 03-54.
¹Completed 30 maps of geochemical parameters for FY03, all available on SOFIA website.
²Manuscript(s) synthesizing productivity data and historical comparisons
²Database of geochemical and productivity data available on SOFIA

Relevance to Greater Everglades Restoration Information Needs: High-resolution water quality data from bimonthly surveys will be used to calibrate salinity and ecologic response to hydrologic condition models, and will provide baseline water quality data to assess restoration impacts. Similarly, productivity monitoring of representative benthic habitats in Florida Bay provides baseline process rates from which to measure ecological response to water quality change. The science objectives in the "USGS science plan in support of Everglades Restoration" document targeted by this project are listed below:

Restoration goal 1A, SO1 - What are the sedimentation rates?
Restoration goal 1B, SO3 - What are current water quality conditions across the South Florida environment?
Restoration goal, 2A, SG3 - What is the current baseline condition for habitats and landscapes within the ecosystem?
Restoration goal 2B, SG3 - What is the current status of the ecosystem and what are trends and variability of important ecosystem indicators.

Key Findings:

• Significant carbonate sediment dissolution occurs within Florida Bay, and may be linked to pCO₂ in the water column. Changing freshwater flow to Florida Bay (and climate change) may change pCO₂ and affect sediment accumulation rates.
• No extreme high salinity events were observed in 2003 salinity surveys as occurred prior to 2002. Bay-wide total alkalinity, total carbon, and CO₂ gas flux data provide additional evidence of a link between pCO₂ and carbonate sediment dissolution.
• Seagrass productivity measured from FY2000 to FY2003 showed rates similar to previous measurements performed in the 1980's and 90's.