Estuaries and Coasts

, Volume 37, Issue 6, pp 1449–1466 | Cite as

Estimates of Natural Salinity and Hydrology in a Subtropical Estuarine Ecosystem: Implications for Greater Everglades Restoration

  • Frank E. Marshall
  • G. Lynn Wingard
  • Patrick A. Pitts


Disruption of the natural patterns of freshwater flow into estuarine ecosystems occurred in many locations around the world beginning in the twentieth century. To effectively restore these systems, establishing a pre-alteration perspective allows managers to develop science-based restoration targets for salinity and hydrology. This paper describes a process to develop targets based on natural hydrologic functions by coupling paleoecology and regression models using the subtropical Greater Everglades Ecosystem as an example. Paleoecological investigations characterize the circa 1900 CE (pre-alteration) salinity regime in Florida Bay based on molluscan remains in sediment cores. These paleosalinity estimates are converted into time series estimates of paleo-based salinity, stage, and flow using numeric and statistical models. Model outputs are weighted using the mean square error statistic and then combined. Results indicate that, in the absence of water management, salinity in Florida Bay would be about 3 to 9 salinity units lower than current conditions. To achieve this target, upstream freshwater levels must be about 0.25 m higher than indicated by recent observed data, with increased flow inputs to Florida Bay between 2.1 and 3.7 times existing flows. This flow deficit is comparable to the average volume of water currently being diverted from the Everglades ecosystem by water management. The products (paleo-based Florida Bay salinity and upstream hydrology) provide estimates of pre-alteration hydrology and salinity that represent target restoration conditions. This method can be applied to any estuarine ecosystem with available paleoecologic data and empirical and/or model-based hydrologic data.


Estuarine restoration Subtropical estuary Hydrology and salinity connectivity Paleoecology Statistical modeling Florida Bay 



This project was funded by the USGS Greater Everglades Priority Ecosystems Science (GEPES) effort, G. Ronnie Best, Coordinator; the National Park Service (Everglades National Park) through the Critical Ecosystems Studies Initiative (CESI); and the US Army Corps of Engineers RECOVER Branch with direction from DeWitt Smith (NPS), Cheryl Buckingham (USACE) and Sue Kemp (USACE). The paleoecological portion of this work was conducted as part of National Park Service (NPS) Study number EVER-00141. Everglades National Park also provided access to and assistance with the hydrologic and salinity station data. We would like to thank Christopher Bernhardt (USGS), Thomas Cronin (USGS), and two anonymous reviewers for their thoughtful comments and suggestions, which have improved this report. Bethany Stackhouse (USGS) created the study area maps (Figs. 1 and 3). Numerous people have assisted in the collection, processing and analyses of the USGS cores and in the development of the modern analog salinity dataset including Robert Halley (retired USGS), Charles W. Holmes (retired USGS), Joel Hudley (University of North Carolina, Chapel Hill), James Murray (USGS), Bethany Stackhouse (USGS), Jeffery Stone (University of Nebraska, Lincoln), and Carleigh Trappe (former USGS contractor). Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Supplementary material

12237_2014_9783_MOESM1_ESM.pdf (29 kb)
ESM 1 (PDF 29 kb)


  1. Anagnostopoulos, G.C. 1997. Optimal linear combinations of experts. Master’s Thesis, University of Central Florida, Orlando, Florida.Google Scholar
  2. Basso, R., and R. Schultz. 2003. Long-term variation in rainfall and its effect on Peace River flow in West-Central Florida. Brooksville, Florida: Hydrologic Evaluation Section, Southwest Florida Water Management District.Google Scholar
  3. Bernhardt, C.E., and D.A. Willard. 2009. Response of the Everglades ridge and slough landscape to climate variability and 20th-century water management. Ecological Applications 19: 1723–1738.CrossRefGoogle Scholar
  4. Brewster-Wingard, G.L., J.R. Stone, and C.W. Holmes. 2001. Molluscan faunal distribution in Florida Bay, past and present: an integration of down-core and modern data. Bulletins of American Paleontology 361: 199–231. Special Volume Number.Google Scholar
  5. Briceño, H.O., and J.N. Boyer. 2010. Climatic controls on phytoplankton biomass in a sub-tropical estuary, Florida Bay, USA. Estuaries and Coasts 33: 541–553.CrossRefGoogle Scholar
  6. Cosby, B.J. 1993. An examination of the relationships of stage, discharges and meteorology in the panhandle and Taylor Slough areas of Everglades National Park to salinity in upper Florida Bay. Report to Everglades National Park. Volumes 1–5. Charlottesville, Virginia: University of Virginia.Google Scholar
  7. Cosby, B., F. Marshall, and W. Nuttle. 2010. Version 6.1 Model structure and salinity simulation. Critical Ecosystem Studies Initiative (Everglades National Park) Cooperative Agreement Number H5284-07-0076. New Smyrna Beach, Florida: Cetacean Logic Foundation, Inc.Google Scholar
  8. Cronin, T.M., C.W. Holmes, G.L. Brewster-Wingard, S.E. Ishman, H.J. Dowsett, D. Keyser, and N. Waibel. 2001. Historical trends in epiphytal ostracodes from Florida Bay: implications for seagrass and macro-benthic algal variability. Bulletins of American Paleontology 361: 159–197.Google Scholar
  9. Davis, S.M., and J.C. Ogden. 1994. Introduction. In Everglades: The ecosystem and its restoration, ed. S.M. Davis and J.C. Ogden, 3–7. Delray Beach, Florida: St. Lucie Press.Google Scholar
  10. Davis, S.M., D.L. Childers, J.L. Lorenz, H.L. Wanless, and T.A. Hopkins. 2005. A conceptual model of ecological interactions in the mangrove estuaries of the Florida Everglades. Wetlands 25: 832–842.CrossRefGoogle Scholar
  11. Diaz, R.J., and R. Rosenberg. 2008. Spreading dead zones and consequences for marine ecosystems. Science 321: 926–929.CrossRefGoogle Scholar
  12. Enfield, D.B., A.M. Mestas-Nunez, and P.J. Trimble. 2001. The Atlantic multidecadal oscillation and its relation to rainfall and river flows in the continental U.S. Geophysical Research Letters 28(10): 2077–2080.CrossRefGoogle Scholar
  13. Erdogan, H. and M.U. Sen. 2010. A unifying framework for learning the linear combiners for classifier ensembles. Proceedings of 20th International Conference on Pattern Recognition 2985–2988.Google Scholar
  14. Fumera, G., and F. Roli. 2005. A theoretical and experimental analysis of linear combiners for multiple classifier systems. IEE Transactions on Pattern Analysis and Machine Intelligence 27(6): 942–956.CrossRefGoogle Scholar
  15. Halley, R.B., K.K. Yates, and C.W. Holmes. 2000. Sea-level rise and the future of Florida Bay in the next century. Abstract for 2000 Greater Everglades Ecosystem Restoration Conference, Naples, Florida, December 11–15, 2000.Google Scholar
  16. Harvey, J.W., J.M. Jackson, R.H. Mooney, and J. Choi. 2000. Interactions between ground water and surface water in Taylor Slough and vicinity, Everglades National Park, south Florida: study methods and appendices. Open File Report 00–483. U.S. Geological Survey, Reston, Virginia.Google Scholar
  17. Hashem, S., and B. Schmeiser. 1995. Improving model accuracy using optimal linear combinations of trained neural networks. IEEE Transactions on Neural Networks and Learning Systems 6(3): 792–794.CrossRefGoogle Scholar
  18. Jones, R.D., and J.N. Boyer, 2001. An integrated surface water quality monitoring program for the south Florida coastal waters: FY2000. Cumulative Report to the South Florida Water Management District (C-10244) and Everglades National Park. Southeast Environmental Research Center, Florida International University, Miami, Florida. Accessed December 5, 2012.
  19. Kachigan, S.K. 1991. Statistical multivariate statistical analysis. New York, New York: Radius Press.Google Scholar
  20. Kelble, C.R., E.M. Johns, W.K. Nuttle, T.N. Lee, R.H. Smith, and P.B. Ortner. 2007. Salinity patterns of Florida Bay. Estuarine Coastal and Shelf Science 71(1–2): 318–334.CrossRefGoogle Scholar
  21. Kotun, K. 2010. A recent history of Taylor Slough hydrology. Abstract. Greater Everglades Ecosystem Restoration Conference 2010. Naples, Florida, July 12–16, 2010.Google Scholar
  22. Langevin, C.D., E.D. Swain, and M.A. Wolfert. 2004. Simulation of integrated surface-water/ground-water flow and salinity for a coastal wetland and adjacent estuary. Open File Report 2004–1097. U.S. Geological Survey, Reston, Virginia. Accessed November 26, 2012.
  23. Lee, T.N., E. Williams, D. Wilson, E. Johns, and N. Smith. 2002. Transport processes linking south Florida coastal ecosystems. In The Everglades, Florida Bay and coral reefs of the Florida Keys: an ecosystem sourcebook, ed. Porter and Porter, 309–342. Boca Raton, Florida: CRC Press.Google Scholar
  24. Lee, T.N., N. Melo, N. Smith, E.M. Johns, R.H. Smith, C.R. Kelble and P.B. Ortner. 2008. On Florida Bay circulation and water exchange with focus on the western subregion. Proceedings, 2008 Florida Bay and Adjacent Marine Systems Science Conference, Naples, Florida, December 8–11, 2008. University of Florida.Google Scholar
  25. Lorenz, J.J. 1999. The response of fishes to physiochemical changes in the mangroves of northeast Florida Bay. Estuaries 22: 500–517.CrossRefGoogle Scholar
  26. Maltby, E., and P.J. Dugan. 1994. Wetland ecosystem protection, management, and restoration: an international perspective. In Everglades: The ecosystem and its restoration, ed. S.M. Davis and J.C. Ogden, 29–46. Delray Beach, Florida: St. Lucie Press.Google Scholar
  27. Marshall, F.E. 2000. Florida Bay salinity transfer function analysis volume 1 of 2: final report, 24. New Smyrna Beach, Florida: Prepared for Florida International University by Cetacean Logic Foundation.Google Scholar
  28. Marshall III, F. E. 2005. RECOVER Southern estuaries performance measures: identification of hydrology-salinity relationships for coastal estuaries and analysis of interim CERP update scenarios. Environmental Consulting & Technology, Inc., New Smyrna Beach, Florida. Accessed November 26, 2012.
  29. Marshall, F. E. 2008. Task 3 - Development of additional multivariate linear regression salinity models for Florida Bay and the southwest Gulf coast, Everglades National Park. Critical Ecosystems Studies Initiative Task Report to Everglades National Park: Cooperative Agreement Number CA H5284-05-0006. Cetacean Logic Foundation, Inc., New Smyrna Beach, Florida. . Accessed December 5, 2012.
  30. Marshall III, F. E., D. Smith, and D. Nickerson. 2004. Using statistical models to simulate salinity variation and other physical parameters in north Florida Bay. Cetacean Logic Foundation, Inc., New Smyrna Beach, Florida. Accessed November 26, 2012.
  31. Marshall, F.E., D.T. Smith, and D.N. Nickerson. 2011. Empirical tools for simulating salinity in the estuaries of Everglades National Park: Estuarine. Coastal and Shelf Science 95: 377–387.Google Scholar
  32. Marshall, F.E., and G.L. Wingard. 2012. Florida Bay salinity and Everglades wetlands hydrology circa 1900 CE: a compilation of paleoecology-based statistical modeling analyses. Open-File Report 2012–1054. US Geological Survey, Reston, Virginia. Accessed November 26, 2012.
  33. Marshall, F.E., G.L. Wingard, and P. Pitts. 2009. A simulation of historic hydrology and salinity in Everglades National Park: Coupling Paleoecologic Assemblage Data with Statistical Models. Estuaries and Coasts 32: 37–53.CrossRefGoogle Scholar
  34. McVoy, C.W., W.P. Said, J. Obeysekera, J. Van Arman, and T. Dreschel. 2011. Landscapes and hydrology of the predrainage Everglades. Gainesville, Florida: University of Florida Press.Google Scholar
  35. Nuttle, W.K. 1997. Central and southern Florida project restudy: salinity transfer functions for Florida Bay and west coast estuaries, volume 1: main report. Prepared for Southeast Environmental Research Program, Florida International University, Miami, Florida by Eco-hydrology, Ottawa, Canada.Google Scholar
  36. Ogden, J.C., S.M. Davis, K.J. Jacobs, T. Barnes, and H.E. Fling. 2005. The use of conceptual ecological models to guide ecosystem restoration in south Florida. Wetlands 25: 795–809.CrossRefGoogle Scholar
  37. Orlando Jr., S.P., M.B. Robblee, and C.J. Klein. 1998. Salinity characteristics of Florida Bay: a review of archived data sets (1955–1995), 32. Silver Spring Maryland: National Oceanographic and Atmospheric Administration, Office of Ocean Resources Conservation and Assessment.Google Scholar
  38. Parker, G.G., G.E. Ferguson, and S.K. Love. 1955. Water resources of southeastern Florida with special reference to the geology and ground water of the Miami area. Water Supply Paper 1255. U.S. Geological Survey, Washington, D.C.Google Scholar
  39. Pitts, P., D. Hallac, D. Deis, and J. Browder. 2005. Establishing targets for salinity in Florida’s Southern Estuaries. Southern Estuaries Sub-team of RECOVER. Jacksonville, Florida: U.S. Army Corps of Engineers.Google Scholar
  40. RECOVER (Restoration Coordination and Verification). 2012. Southern Coastal Systems performance measure: salinity in Florida Bay. Accepted June 2012, by Comprehensive Everglades Restoration Plan Agency Authorities. Accessed July 9, 2013.
  41. Revenga C., J. Brunner, N. Henninger, K. Kassem, and R. Payne. 2000. Pilot analysis of global ecosystems: freshwater ecosystems: World Resources Institute Report. Accessed December 13, 2013.
  42. Saunders, C.J., M. Gao, J.A. Lynch, R. Jaffe, and D. Childers. 2006. Using soil profiles of seeds and molecular markers as proxies for sawgrass and wet prairie slough vegetation in Shark Slough, Everglades National Park. Hydrobiologia 569: 475–492.CrossRefGoogle Scholar
  43. Schaffranek, R. W., T. J. Smith, and C. W. Holmes. 2001. An investigation of the interrelation of Everglades hydrology and Florida Bay dynamics to ecosystem processes in south Florida. Fact Sheet FS-49-01. U.S. Department of Interior, U.S. Geological Survey, Reston, Virginia.Google Scholar
  44. Scully, S.P. 1986. Florida Bay salinity concentration and groundwater stage correlation and regression. West Palm Beach, Florida: Internal Memorandum, South Florida Water Management District.Google Scholar
  45. Sklar, F.H., M.J. Chimney, S. Newman, P. McCormick, D. Gawlik, S. Miao, C. McVoy, W. Said, J. Newman, C. Coronado, G. Crozier, M. Korvela, and K. Rutchey. 2005. The ecological-societal underpinnings of Everglades restoration. Frontiers in Ecology and the Environment 3(3): 161–169.Google Scholar
  46. Smith, T.J., J.H. Hudson, M.B. Robblee, G.V.N. Powell, and P.J. Isdale. 1989. Freshwater flows from the Everglades to Florida Bay: a historical reconstruction based on fluorescent banding in the coral Solenastrea bournoni. Bulletin of Marine Science 44: 274–282.Google Scholar
  47. Swain, E.D., M.A. Wolfert, J.D. Bales, and C.R. Goodwin. 2004. Two-dimensional hydrodynamic simulation of surface-water flow and transport to Florida Bay through the Southern Inland and Coastal Systems (SICS). Water-Resources Investigations Report 03–4287. Reston, Virginia: U.S. Geological Survey.Google Scholar
  48. Swart, P.K., G. Healy, L. Greer, M. Lutz, A. Saied, D. Anderegg, R.E. Dodge, and D. Rudnick. 1999. The use of proxy chemical records in coral skeletons to ascertain past environmental conditions in Florida Bay. Estuaries 22: 384–397.CrossRefGoogle Scholar
  49. Tabb, D. 1967. Prediction of estuarine salinities in Everglades National Park, Florida by the use of ground water records. PhD Dissertation, University of Miami, Miami, Florida. 107 pp.Google Scholar
  50. U.S. Army Corps of Engineers. 1999. Central and south Florida comprehensive review study. Final integrated feasibility report and programmatic environmental impact statement. U.S. Army Corps of Engineers, Jacksonville District Office, Jacksonville, Florida. Accessed November 26, 2012.
  51. U.S. Army Corps of Engineers. 2012. Comprehensive Everglades Restoration Plan Southern Coastal Systems salinity performance measure. Accessed December 23, 2012.
  52. Ueda, N. 2000. Optimal linear combination of neural networks for improving classification performance. IEEE Transactions on Pattern Analysis and Machine Intelligence 22(2): 207–215.CrossRefGoogle Scholar
  53. UNESCO. 1985. The international system of units (SI) in oceanography, UNESCO Technical Papers No. 45, IAPSO Pub. Sci. No. 32, Paris, France.Google Scholar
  54. Wachnicka, A., E. Gaiser, and L.S. Collins. 2013. Correspondence of historic salinity fluctuations in Florida Bay, USA, to atmospheric variability and anthropogenic changes. Journal of Paleoliminology 49: 103–115.CrossRefGoogle Scholar
  55. Wang, J.D., J. Van De Kreeke, N. Krishnan, and D. Smith. 1994. Wind and tide response in Florida Bay. Bulletin of Marine Science 54: 579–601.Google Scholar
  56. Willard, D.A., C.E. Bernhardt, D.A. Korejwo, and S.R. Meyers. 2005. Impact of millennial-scale Holocene climate variability of eastern North American terrestrial ecosystems: pollen-based climatic reconstruction. Global and Planetary Change 47: 17–35.CrossRefGoogle Scholar
  57. Willard, D.A., C.E. Bernhardt, C.W. Holmes, B. Landacre, and M. Marot. 2006. Response of Everglades tree islands to environmental change. Ecological Monographs 76(4): 565–583.CrossRefGoogle Scholar
  58. Wingard, G.L., T.M. Cronin, and W. Orem. 2007a. Ecosystem history. In Florida Bay Science Program: a synthesis of research on Florida Bay, eds. J.H. Hunt and W. Nuttle, 9–29. St. Petersburg: Fish and Wildlife Research Institute Report TR-11.Google Scholar
  59. Wingard, G.L., and J.W. Hudley. 2012. Application of a weighted-averaging method for determining paleosalinity: a tool for restoration of south Florida’s estuaries. Estuaries and Coasts 35(1): 262–280.CrossRefGoogle Scholar
  60. Wingard, G.L., J.W. Hudley, C.W. Holmes, D.A. Willard, and M. Marot. 2007b. Synthesis of age data and chronology for Florida Bay and Biscayne Bay Cores collected for the Ecosystem History of South Florida’s Estuaries Projects. U.S. Geological Survey, Open File Report 2007–1203. Reston, Virginia. Accessed November 26, 2012.
  61. Zapata-Rios, X., and R.M. Price. 2012. Estimates of groundwater discharge to a coastal wetland using multiple techniques: Taylor Slough, Everglades National Park, USA. Hydrogeology Journal 20: 1651–1668.CrossRefGoogle Scholar

Copyright information

© Coastal and Estuarine Research Federation 2014

Authors and Affiliations

  • Frank E. Marshall
    • 1
  • G. Lynn Wingard
    • 2
  • Patrick A. Pitts
    • 3
  1. 1.Cetacean Logic Foundation, IncorporatedNew Smyrna BeachUSA
  2. 2.U.S. Geological SurveyRestonUSA
  3. 3.U.S. Fish and Wildlife ServiceVero BeachUSA

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