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Project Work Plan

U.S. Geological Survey Greater Everglades Science Initiative (Place-Based Studies)

Fiscal Year 2004 Project Work Plan

A. GENERAL INFORMATION:

Project Title: Historical Changes in Salinity, Water Quality and Vegetation in Biscayne Bay
Project Start Date: 3/15/02 Project End Date: 9/30/05
Project Funding: USGS Place-Based Studies Initiative, South Florida Water Management District
Principal Investigator: G. Lynn Wingard
Email address: lwingard@usgs.gov
Phone: 703-406-3237 Fax: 703-648-6953
Mail address: MS 926A, USGS National Center
Reston, VA 20192

Other Investigator(s): Thomas Cronin
Email address: tcronin@usgs.gov
Phone: 703-648-6363 Fax: 703-648-6953
Mail address: MS 926A, USGS National Center
Reston, VA 20192

Other Investigator(s): Debra Willard
Email address: dwillard@usgs.gov
Phone: 703-648-5320 Fax: 703-648-6953
Mail address: MS 926A, USGS National Center
Reston, VA 20192

Other Investigator(s): Charles Holmes
Email address: cholmes@usgs.gov
Phone: 727-893-3100 X3056 Fax: 727-803-2032
Mail address: USGS Center for Coastal Research
600 Fourth Street South
St. Petersburg, FL 33701

Other Investigator(s): William Orem
Email address: borem@usgs.gov
Phone: 703-648-6273 Fax: 703-648-6419
Mail address: MS 956, USGS National Center
Reston, VA 20192

Other Investigator(s): Peter Swart
Email address: swart@rsmas.miami.edu
Phone: 305-361-4103 Fax: 305-361-4632
Mail address: University of Miami
RSMAS 4600 Rickenbacker Causeway
Miami, FL 33031

Other Investigator(s): Gary Dwyer
Email address: gsd3@duke.edu
Phone: 919-681-8164 Fax: 919-684-5833
Mail address: Division of Earth and Ocean Sciences
Corner of Research and Science Drives
103 Old Chemistry Building
Duke University
Durham, NC 27708

Other Investigator(s): Scott Ishman
Email address: sishman@geo.siu.edu
Phone: 618-453-7377 Fax: 618-453-7393
Mail address: Geology Department
Mail Code 4324
Southern Illinois University
Carbondale, Ill 62901

Other Investigator(s): Evelyn Gaiser
Email address: gaisere@fiu.edu
Phone: (305) 348-6145 Fax: (305) 348-4096
Mail address: Department of Biology and SERC
Florida International University
Miami, FL 33199

Project Summary:

During the last century, Biscayne Bay has been greatly affected by anthropogenic alteration of the environment through urbanization of the Miami/Dade County area and alteration of natural flow. The sources, timing, delivery, and quality of freshwater flow into the Bay, and the shoreline and sub-aquatic vegetation have changed. Current restoration goals are attempting to restore natural flow of fresh water into Biscayne and Florida Bays and to restore the natural fauna and flora, but first we need to determine pre-alteration baseline conditions in order to establish targets and performance measures for restoration. This project is designed to examine the natural patterns of temporal change in salinity, water quality, vegetation, and benthic fauna in Biscayne Bay over the last 100-300 years and to examine the causes of change.

Project Objectives and Strategy:

The objectives of this project are to examine in broad context the historical changes in the Biscayne Bay ecosystem at selected sites on a decadal-centennial scale, and to correlate these changes with natural events and anthropogenic alterations in the South Florida region. Specific emphasis will be placed on historical changes to 1) amount, timing, and sources of freshwater influx and the resulting effects on salinity and water quality; 2) shoreline and sub-aquatic vegetation; and 3) the relationship between sea-level change, onshore vegetation, and salinity. In addition, a detailed examination of historical seasonal salinity patterns will be derived from biochemical analyses of ostracodes, foraminifera, molluscs, and corals. The corals will allow us to compare marine and estuarine trends, examine the linkage between the two systems, and will provide precise chronological control. Land management agencies (principally SFWMD, ACOE and Biscayne NP) can use the data derived from this project to establish performance criteria for restoring natural flow, and to understand the consequences of altered flow. These data can also be used to forecast potential problems as upstream changes in water delivery are made during restoration.

The strategy for FY 04 is to focus on analyzing the sediment cores collected in June 2003 in Biscayne Bay and to continue additional analyses on cores collected in previous years. Sampling and analyses of selected cores will follow methods established by the Florida Bay Ecosystem History Projects (Brewster-Wingard, USGS, GD; Orem, USGS, GD). Age models will be refined for Biscayne Bay in FY04 by obtaining additional carbon-14 dates on cores, and by doing directed sampling at sites to understand the variations in radioisotopes. Cores from the nearshore wetlands will be collected and analyzed in FY04 and the data compared and compiled with results from the estuarine cores.

Modern surveys and sampling of selected sites in Biscayne Bay will continue to be gathered. These data serve as proxy data for interpreting the downcore faunal and floral remains. Data from 28 sites in Florida Bay (collected 2X/year beginning in 1995) also is utilized along with ongoing experimental data from the Florida Bay Paleosalinity Project. A series of downcore geochemical analyses will evaluate past changes in nutrients (C,N,P,S), shell geochemistry (salinity and temperature), and stable isotopes (salinity and sources of water). The analyses of the indicator-species and the shell geochemistry work will be an extension of ongoing and completed ecosystem history work in Florida Bay that has focused on historical salinity patterns (Cronin, Brewster-Wingard, and others).

P. Swart, U. Miami, analyzed stable isotopic data from water samples in FY03. These data will be compared with downcore isotopic analyses of microfauna to determine the origin of variations in salinity in Biscayne Bay. Freshwater from precipitation, runoff and groundwater have unique O and H isotopic signatures, so the sources of freshwater influx can be traced. These data are essential in assessing the impact of water management practices on the Bay and the input of groundwater into the system. This method was developed in Florida Bay, utilizing samples collected since 1993, and will now be applied to Biscayne Bay.

Near the end of FY04 and into FY05, additional data gaps and information needs will be determined and a few new cores may be collected from strategic sites. Analyses will be continued into FY05 and results of all core analyses will be compiled and articles/reports written and presented to client agencies.

Potential Impacts and Major Products:

One of the primary restoration goals identified by the South Florida Restoration Task Force - to "get the water right." The Comprehensive Everglades Restoration Plan (CERP) Biscayne Bay Coastal Wetlands Project (BBCW) has specifically identified the importance of understanding freshwater flow into Biscayne Bay and the changes incurred due to alterations in flow. This project fulfills information needs for several CERP Tasks, including the following. The project directly addresses Task 3006-7: to "conduct isotopic/paleoecologic studies for the determination of historical salinities/freshwater flows for Biscayne Bay;" and provides data for Tasks 3007-2, 3007-3, 3050-4 and 3050-5 by contributing to the understanding of the relationships between salinity and the health and distribution of sub-aquatic vegetation and fauna. Tracking changes in onshore vegetation over time will contribute to Task 3007-9 and data on historical changes in nutrient supply will contribute to CERP Task 3090-4. The data provided by this project will evaluate the potential impacts of restoration changes and will provide targets for restoration of historical flow. This will allow the Army Corps of Engineeers (ACOE), the South Florida Water Management District (SFWMD) and other agencies responsible for guiding CERP and CESI to make informed decisions that will protect Biscayne Bay and Biscayne National Park. These data allow the land managers to set realistic performance measures for restoration that take into account the natural ranges of variation that exist within the ecosystem. Part of this research is funded by an OFA with SFWMD (Trisha Stone, project manager).

Data on individual cores and modern monitoring work will be made available online following completion of analysis at the Ecosystem History Project website http://sofia.usgs.gov/flaecohist/ and the University of Miami stable isotope web site http://mgg.rsmas.miami.edu/groups/sil/index.htm. The University of Miami site also will release oxygen, hydrogen, and carbon isotopic data on South Florida coastal waters collected since 1993. Open-file reports on each core and a synthesis article for a scientific journal will be compiled. A special publication highlighting the research would be prepared for a non-scientific audience, including the stakeholders and the public, and could be made available at Biscayne NP. In addition, results will be reported at scientific meetings, and to client agencies.

Time Frame: Project will run from 3/15/02 to 9/30/05

Cooperators and Collaborators:
Florida, Florida International University, Seagrass Biologist : Contact: James Fourqurean
Florida, Florida International University, Geochemist: Contact Joe Boyer
Florida, Florida Marine Research Institute: Paul Carlson, Barbara Blakesley
Florida, State Agencies, Florida Department of Environmental Protection, Keys Marine Laboratory; field station: Contact: Lisa Tipsword
Virginia, University of Virginia, Seagrass Biologist: Contact: Jay Zieman

Clients:
Florida, State Agencies, South Florida Water Management District: Contacts: Trisha Stone, Rick Alleman (Formal OFA in place 3/15/02 to 3/30/03; Year two contract should be implemented by 8/1/03)
Department of Interior, National Park Service, Biscayne National Park: Contacts: Richard Curry, Monika Mayer, and Sarah Bellmund
Department of Interior, U.S. Fish and Wildlife Service: Contact: Heather McSharry
Department of Defense, U.S. Army, U.S. Army Corps of Engineers, Jacksonville District, South Atlantic Division: Contact: Shelly Trulock
Department of Commerce, National Oceanic and Atmospheric Administration, Florida Keys National Marine Sanctuary: Contact: William Causey
Florida, Local Agencies, Dade County Environmental Resource Management (DERM): Contact: Gwen Burzycki

B. WORK PLAN

Title of Task 1: Geochronology and paleoecology of Biscayne Bay cores
Task Funding: PBS and OFA with SFWMD
Task Leaders:

G. Lynn Wingard
Phone: (703) 648-5352
FAX: (703) 648-5420

Charles W. Holmes
Phone: (727) 893-3100 X3056
FAX: 727-803-2032

Task Status (proposed or active): Active
Task priority: High
Time Frame for Task 1: 3/15/02 to 9/30/05
Task Personnel: G. Lynn Wingard, Charles W. Holmes, Thomas Cronin, Scott Ishman (U. Southern Illinois), Deb Willard, Evelyn Gaiser (Florida International University), James Murray, Rob Stamm, Marci Marot and technical and database support to be hired or assigned.

Task Summary and Objectives: The initial and primary task is to determine the age of the selected cores, the general salinity history, the presence of sub-aquatic vegetation (SAV), and the probable abundance of SAV using established geochronologic and paleoecologic methods. This task lays the groundwork for additional analyses as well as providing necessary data for the final interpretation of the cores. The purpose of the overall project is to determine the changes in water quality and salinity over time, and the corresponding changes in onshore and sub-aquatic vegetation. The first step is to determine if the core has a good chronology (i.e. the core has not been disrupted) and if it contains faunal remains for analyses. If the core meets these criteria, then additional work can proceed. If the chronology is not good, or if there are no preserved fauna, than another core will be selected and the tasks repeated until we identify a core that meets these criteria. The chronologic data will be used to interpret all additional analyses. Paleoecological methods also will be used to provide data on the general trends within the core in terms of salinity, SAV, and changes in water quality and nutrient supply.

Work to be undertaken during the proposal year and a description of the methods and procedures:
Six cores were collected at three sites in FY03 (Middle Key, Inlet north of Black Point, and Chicken Key). FY04 project work will focus on analyzing these cores. Faunal samples are processed using standard methods and all fractions are retained for analyses. A portion of the less than 63-micron fraction is used for Pb-210 geochronology and selected shells or plant material will be used for radiocarbon dating. In FY04 special emphasis will be placed on refining the age models for the FY02 cores by obtaining modern sediment samples to examine background radioisotopes in Biscayne Bay. Additional carbon-14 ages will be obtained for the FY02 cores as well. The same methods will be applied to the FY03 cores.

The greater than 63-micron fraction of the cores is sorted for faunal analyses; ostracodes, molluscs and benthic forams are picked, sorted and identified. A small portion of core material is retained and processed for diatoms (Gaiser, FIU) and pollen (Willard). Percent abundance is calculated for the faunal, diatom, and pollen data, and these data are compared to data from 28 sites in modern Florida Bay where faunal and floral associations have been studied between 1996-2000 and to sites established in Biscayne Bay (see work listed in Task 2). These modern data serve as proxies for interpreting the down-core data. The down-core faunal and floral assemblages and the presence or absence of key indicator species allow interpretation of trends in salinity, water quality and the presence of SAV at the core sites. Data obtained in FY04 will be compiled with data from FY03 and older cores from Biscayne to determine trends. Any information gaps and additional questions will be identified. If necessary, a few additional cores may be selected and processed to address specific information needs.

For FY05, analyses and compilations will be completed, and final reports, and journal articles compiled.

Planned Outreach:

Data from cores will be compiled, analyzed, and presented as a poster or talk at conferences and meetings with clients. Additionally, all data will be made available on line at http://sofia.usgs.gov/flaecohist/. This web site provides links to data, posters and open-file reports produced by the South Florida Ecosystem History Projects. Open File Reports will be produced on the cores and distributed to the clients and cooperators. After the analyses of several cores have been completed, a journal article for a scientific publication will be produced and a fact sheet or information circular that would highlights the research for the stakeholders. The audience for this special publication would be the non-scientists among the stakeholder agencies (NPS, ACOE, SFWMD) and the general public via NPS. In addition, we plan to work with the Visitors Center at Biscayne NP to develop an exhibit illustrating how cores can provide information about an ecosystem.

Title of Task 2: Patterns, Causes, and Impacts of Salinity Changes in Biscayne Bay
Task Funding: PBS and OFA with SFWMD
Task Leaders:
Thomas Cronin
Phone: 703-648-6363
Fax: 703-648-6953
Task Status (proposed or active): Active
Task priority: High
Time Frame for Task 2: 3/15/02 to 9/30/05
Task Personnel: Thomas Cronin, G. Lynn Wingard, Gary Dwyer, Peter Swart, Rob Stamm, and technical support to be hired or assigned

Task Summary and Objectives:
Determine salinity history of several regions in Biscayne Bay for the period prior to and during large-scale 20th century urbanization and water diversion using salinity proxies from sediment cores from Biscayne Bay and Card and Barnes Sounds. Relate salinity variability to changes in fresh water flow due to land-use changes and natural variability in rainfall, freshwater runoff and water temperature (evaporation) and determine the extent to which water diversion disrupted natural patterns of salinity. Develop method to use oxygen isotope ratios in foraminifers as proxy of past salinity and/or temperature changes. Compare and "splice" together the sediment core records of paleosalinity and paleotemperature with instrumental records of rainfall, bay salinity and temperature obtained from water monitoring. The reconstructed record of physical and biological conditions in Biscayne Bay will be compared to the history of water quality obtained by W. Orem (task 6). Biscayne Bay ecosystem and salinity history also will eventually be compared to records from Florida and Manatee Bays to examine regional trends.

Work to be undertaken during the proposal year and a description of the methods and procedures:
Work in FY 2004 will involve measurement of faunal and geochemical proxies of salinity and temperature from sediment cores taken in 2002 and 2003 and if time permits, an additional site in northern Biscayne Bay, near the Rickenbacker Causeway (collected in 1997), will be examined. Proxy methods include 1) oxygen isotope analyses of benthic foraminifera (Cronin, Ishman and Swart), 2) trace elemental (magnesium/calcium ratios) of ostracodes (Cronin and Dwyer), 3) morphological indicators of temperature (shell size)(Cronin) and 4) relative proportions of species of forams, ostracodes and molluscs indicative of specific salinity ranges (i.e. oligohaline, mesohaline, etc.)(related to task 1 assemblage analyses). The stable isotopic and trace elemental analyses will be carried out with cooperators using mass spectrometry and direct current plasma emission spectrometry at University of Miami and Duke University, respectively. The use of paired analyses of stable isotopes of forams and Mg/Ca ratios in ostracodes should allow the quantification of changes in salinity and temperature and the impact of these changes could then be assessed from the faunal analyses of benthos from the same samples. Selected intervals identified as representing extreme salinity conditions may also be studied for seasonal salinity variability using molluscan shell chemistry, depending on preservation in cores and status of mollusk calibration studies (related to Paleosalinity as a Key for Success Criteria in South Florida Restoration Project; Wingard, and others).

Modern forams, ostracodes, and mollusks and associated water samples will continue to be collected in FY04 for the following purposes: (1) to calibrate the oxygen isotopic composition of foraminiferal shells to water isotope ratios and salinity for application to sediment core forams; (2) to improve understanding of the salinity tolerance of indicator species in Biscayne Bay; (3) to determine the local radiocarbon "correction" for Biscayne Bay. These modern calibration sites are located at core sites and along salinity transects. The sites will be located strategically in relation to P. Swart's (see Task 3) and G. Dwyer's water chemistry stations, and will correspond to the monitoring sites established in Task 1 for the benthic faunal surveys.

Core data and data from modern monitoring sites will be compiled and written up in FY05.

Planned Outreach:
In addition to reports listed in Task 1, the following will be done: presentations to Biscayne National Park personnel and South Florida Water Management District, write Fact Sheet, summarize results for modeling community.

Title of Task 3: Origin of salinity variations in Biscayne Bay
Task Funding: PBS and OFA with SFWMD
Task Leaders:
Peter Swart
Phone: (305) 361-4103
FAX: (305) 361-4632

Task Status (proposed or active): Completed
Task priority: Completed
Time Frame for Task 1: 3/15/02 to 9/30/03.
Task Personnel: Peter Swart, University of Miami, Réne Price, University of Miami (Under USGS Contract: G. Lynn Wingard Technical Liason)

Task Summary and Objectives:
This task was designed to answer the question of whether variations in salinity, a common feature of the coastal environments of Biscayne, are a result of terrestrial runoff, ground water input, or local precipitation. By analyzing stable oxygen and hydrogen isotopes in the water we can determine whether the source of freshwater influx is from rainfall, overland flow, or groundwater input. This information is vital in assessing (i) the impact of water management changes within the terrestrial Everglades on the coastal ecosystem, (ii) the input of groundwater into the coastal systems, and (iii) identifying which systems are susceptible to anthropogenic water use decisions.

Work to be undertaken during the proposal year and a description of the methods and procedures: Task completed in FY03. Any additional work will be conducted by U. Miami in conjunction with other work in Biscayne Bay.

Planned Outreach:
Data and maps are available on the University of Miami stable isotope web site http://mgg.rsmas.miami.edu/groups/sil/index.htm and have been made available to clients and colleagues at meetings and conferences. Data from this task will contribute to final products for project, discussed under Task 1.

Title of Task 4: Palynological analysis and reconstruction of shoreline vegetation
Task Funding: PBS and OFA with SFWMD
Task Leaders:
Debra Willard
Phone: 703-648-5320
FAX: 703-648-6953

Task Status (proposed or active): Active
Task priority: Medium
Time Frame for Task 4: 3/15/02 to 9/30/05
Task Personnel: Debra Willard, and technical support to be assigned or hired.

Task Summary and Objectives:
Reconstruct vegetational trends at selected wetlands sites using pollen and seeds preserved in sediment cores. Although temporal resolution depends on sedimentation rates at core sites, vegetational changes on a decadal scale should be identifiable. Also, document fire history of region through quantitative analysis of charcoal in sediment cores.

Work to be undertaken during the proposal year and a description of the methods and procedures:
Analyze pollen assemblages from cores collected for task 1 during FY03 and from marsh cores to be collected in FY04; initial examination will be at 10 cm increments, with other samples filled in as appropriate. Vegetational trends will be reconstructed through statistical comparison with database of ~200 surface samples collected in different vegetation types throughout the Everglades; secondarily, changes in hydroperiod and water depth will be estimated from vegetational proxies. Charcoal analyses will be undertaken using chemical digestion to isolate charcoal and morphometric analysis to quantify charcoal in each sample. Geochronologies established as part of task 1 will allow determination of the timing of changes in vegetation or charcoal abundance and correlation with specific environmental or anthropogenic changes.

Based on results from initial wetland cores, additional cores may be collected near the end of FY04 or early FY05. All analyses will be completed and compiled in FY05.

Planned Outreach:
In addition to reports listed in Task 1, presentations will be made to Biscayne National Park personnel and South Florida Water Management District, and results will be summarized for modeling community.

Title of Task 5: Isotopic analyses of corals from Biscayne National Park
Task Funding: PBS and OFA with SFWMD
Task Leaders:
Peter Swart (University of Miami, RSMAS)
Phone: (305) 361-4103
FAX: (305) 361-4632

Task Status (proposed or active): Completed
Task priority: Completed
Time Frame for Task 5: 3/15/02 to 9/30/03. Supported by OFA.
Task Personnel: Peter Swart, University of Miami, Réne Price, University of Miami (Under USGS Contract: G. Lynn Wingard Technical Liason)

Task Summary and Objectives:
Biscayne National Park contains the northern-most extension of the Florida Keys Reef Tract, extending from Fowey Rocks in BNP 130 miles south to the Marquesas. The Florida Reef Tract is a unique natural resource - the only reef ecosystem in the continental US and among the largest bank reef systems in the world. Yet, this unique ecosystem is threatened by "upstream" changes in freshwater flow through the terrestrial Everglades. It is critical to understand the linkages between the terrestrial system, Biscayne Bay and the Reef Tract prior to implementing substantial restoration changes. This task examines these linkages by comparing isotopic records obtained from coral to records from the near shore cores collected and analyzed in Tasks 1 and 2, and to water chemistry data collected in Task 3. In addition in provides a long term continuous record of offshore water chemistry that will provide information on the relationship of coral health to water chemistry pre- and post-alteration of terrestrial flow. If corals can be located within the Bay and permission to sample them obtained, additional comparisons can be made between offshore and Bay waters.

Work to be undertaken during the proposal year and a description of the methods and procedures:
Completed in FY03. Any additional work will be done independently by U. Miami in connection with other ongoing projects.

Planned Outreach:
Data and results have been made available to clients and colleagues at meetings and conferences. Data from this task will contribute to final products for project, discussed under Task 1.

Title of Task 6: Geochemical History of Biscayne Bay: Nutrients and Organics
Task Funding: PBS and OFA with SFWMD
Task Leaders:
William H. Orem
Phone: 703-648-6273
FAX: 703-648-6419

Task Status (proposed or active): Active
Task priority: Medium
Time Frame for Task 6: 10/1/02 to 9/30/05
Task Personnel: William H. Orem, Harry E. Lerch, Marisa Beck

Task Summary and Objectives:
Nutrients from agricultural and urban runoff are causing eutrophication and microalgal blooms in many of the estuaries in South Florida, including Biscayne Bay. The effects of this excess nutrient input on biotic assemblages within the estuaries, however, are not understood, but may be substantial. Eutrophication and microalgal blooms may be responsible for seagrass dieoff in Florida Bay, and coral mortality in the Florida Keys. In Biscayne Bay, seagrass dieoff, changes in microalgal population structures, and changes in other benthic species may be occurring. Linking eutrophication to these changes in the biotic community, however, is a difficult problem.

Our major objectives are to determine the historical record of eutrophication in Biscayne Bay and to evaluate the linkage between eutrophication and changes in the biotic community in the bay. The approach we will take in this task is to examine the historical record of nutrients in Biscayne Bay from dated sediment cores. Results will also be compared to water flow records to determine if known changes in the water control system of South Florida may correspond to distinct nutrient changes within the cores. Historical changes in sulfur content of the cores will also provide information on historical changes in salinity in Biscayne Bay related to construction of canals within the Everglades (salinity data will be compiled with tasks 1 and 2). We will also examine organic geochemical markers of seagrass and microbial communities in the cores to determine historical changes in these biota. These results will be compiled with faunal and floral data from tasks 1 and 2. Comparing the timing of changes in nutrient input to that of changes in the biological community will allow a determination of whether eutrophication of the estuary and changes in biota are directly linked.

Work to be undertaken during the proposal year and a description of the methods and procedures:
Six cores from three sites were collected in FY03 (Task 1). Splits of the <63-micron fraction from these cores will be analyzed for nutrient history studies. Results from 210Pb and 137Cs dating of these cores, and paleoecological studies will be available for comparison to the nutrient data. In FY04, nutrients will be analyzed from every 2-cm interval in the FY03 cores, meeting the criteria defined in Task 1. Additional piston coring will be conducted as needed in FY04 using existing equipment available to this project task. This additional coring may be needed for obtaining fresh core material (unoxidized sediment) for organic biomarker studies. Processing procedures and sectioning of these additional cores will follow the same protocol as that used in the FY02 coring. Work in FY05 will involve continued analysis of the core samples, especially the time-consuming biomarker work, and compilation of the results.

Sediment samples will be analyzed for total and organic C, total N, and total S using a Leco elemental analyzer available in USGS organic geochemistry labs (Orem) in Reston, VA. Total P content will be analyzed using a standard geochemical method involving baking at 500°C, extraction in acid, and colorimetric analysis. All equipment for this procedure is also available at USGS labs in Reston. Organic geochemical studies will involve the use of published methods. These methods involve soxhlet extraction of biomarkers from sediments, isolation procedures involving column chromatography, and identification and quantification using GC and GC/MS. All organic geochemical equipment and instrumentation needed from this work is available in lab facilities at the USGS in Reston, VA. All geochemical data will be plotted down-core, and compared to results of other tasks. Accumulation rates for total and organic C, total N, total P, and total S will be calculated using sediment accumulation rates calculated from 210Pb dating and the concentrations of these chemical species in the sediments. Accumulation rates for these elements in Taylor Slough and the C-111 Basin, and eastern Florida Bay have already been published by Orem. Comparison of accumulation rates in Biscayne Bay and Florida Bay may provide additional insights into processes and flow patterns.

Planned Outreach:
Data and results will be presented at workshops, public forums, and meetings in South Florida. USGSA publication and Fact Sheet are anticipated products for FY03, followed by peer-reviewed journal articles to be produced in FY04. Data and results from this task will contribute to final products for the project, discussed under Task 1. In addition, data from this project will contribute to production of a map of accumulation rates in the Biscayne Bay, Eastern Florida Bay, and Taylor Slough region, which will provide a blueprint of nutrient contamination in this region for management use.

C. BRIEF DESCRIPTION ON HOW PROJECT TASKS SUPPORT THE DOI AND USGS EVERGLADES RESTORATION SCIENCE PLANS

One of the primary restoration goals identified by the South Florida Restoration Task Force is to "get the water right." The DOI Science Plan lists "analysis of historic conditions" as an information need for the Biscayne Bay Coastal Wetlands Project. The USGS Science Plan for South Florida has identified five primary science objectives (SO) to address the needs of restoration and this project meets 3 of those objectives for Biscayne Bay:

SO2. Determine the historical setting of the Greater Everglades ecosystem

SO3. Establish baselines and variations for restoration targets

SO5. Predict ecosystem response to anthropogenic and natural change

This project fulfills these information needs and objectives by providing information on natural patterns of change in salinity, water quality, vegetation, and benthic fauna in Biscayne Bay and the nearby wetlands over the last 100-500 years. Data on historical patterns of change over centennial and decadal time scales allows CERP project managers to set realistic restoration targets that take natural patterns of change into consideration, and provides predictive capabilities on how the system will respond to future changes.



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