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projects > impacts of hydrologic and climatic change on greater everglades marl prairies, marshes, and sloughs > work plan

Project Work Plan

Department of Interior USGS GE PES
Fiscal Year 2012 Study Work Plan

Study Title: Impacts of Hydrologic and Climatic Change on Greater Everglades Marl Prairies, Marshes, and Sloughs
Study Start Date: 10/1/2006 Study End Date: 9/30/2012
Web Sites: http://sofia.usgs.gov/projects/index.php?project_url=impacts_gepms
Location (Subregions, Counties, Park or Refuge): Everglades National Park, Big Cypress National Preserve, A.R.M. Loxahatchee National Wildlife Refuge, Water Conservation Areas 2 and 3
Funding Source: GE PES
Other Complementary Funding Source(s): None at this time
Funding History: FY07; FY08; FY09; FY10; FY11; FY12.
Principal Investigator(s): Debra A. Willard
Study Personnel: C. Bernhardt, B. Landacre, M. Marot, T. Sheehan, J. Sah, P. Conrads.
Supporting Organizations: South Florida Water Management District; Everglades National Park; A.R.M. Loxahatchee National Wildlife Refuge, Big Cypress National Preserve, US Fish & Wildlife Service.
Associated / Linked Studies: Development and Stability of Everglades Tree Islands, Ridge and Slough, and Marl Prairies (ended 2006); Synthesis of South Florida Ecosystem History Research (ended in FY07); Sea Level Rise and Climate Change - Impacts on the Greater Everglades Ecosystem and Restoration.

Overview & Objective(s): The initial objective of this project is reconstruction of marl prairie vegetation and hydroperiod for the last few centuries to evaluate impacts of climate variability and anthropogenic alteration of hydrology on this critical habitat. This research builds upon previous work throughout the Greater Everglades wetland that documents responses of tree islands and the ridge and slough landscape to natural and anthropogenic hydrologic change (completed 2007). This task requires: 1) multi-proxy analyses (pollen, charcoal, carbon isotopes, geochronology) of sediment cores from marl prairie habitats; and 2) refinements to the existing Everglades pollen calibration dataset by collecting and analyzing surface samples along vegetation transects established by M. Ross and colleagues at Florida International University. An additional objective of the project is refinement of down-core estimates of hydroperiod and stage by calibrating results from new and existing cores with nearby stream gage records. For this task, fine sampling of several new cores will be paired with stream gages with the longest records to calibrate pollen-based estimates of hydroperiod using instrumental records. The resulting refinements will be used to re-evaluate paleohydrologic evidence from ~75 existing sites and develop an Everglades-wide hydrologic reconstruction for pre- and post-drainage time slices. Proxy records preserved in Everglades sediments provide an archive of wetland response to a series of natural and anthropogenic hydrologic experiments during the last few millennia and document the impacts of multidecadal climate processes on wetland communities. By extending the period of record of observations in this "living laboratory of change, these data improve our ability to forecast future ecosystem response to a broad range of climate and management scenarios.

Specific Relevance to Major Unanswered Questions and Information Needs Identified: (Page numbers below refer to DOI Science Plan.)

The importance and application of ecosystem history research to restoration goals has been identified in the DOI Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida, the USGS Science Plan for south Florida, and the Everglades Multi-Species Avian Ecology and Restoration Review. The DOI Science Plan lists the need to "ensure that hydrologic performance targets accurately reflect the natural predrainage hydrology and ecology as one of its three primary science goals (DOI Science Plan 2005, p. 16). The USGS Science Plan for south Florida (2007 draft, p. 7) identifies five primary science goals, the second of which is to "determine the historical ecological setting of the Everglades. The Everglades Multi-Species Avian Ecology and Restoration Review recognized the value of paleoecological research in understanding patterns and causes of historical vegetation changes andpos recommended continued research to synthesize and integrate results from previous and ongoing paleoecological studies to inform restoration planning (SEI, 2007, pl 22). The overall goal of this project, and related previous ecosystem history projects, is to document the predrainage distribution of vegetation and reconstruct paleohydrology of marl prairies, marshes, and sloughs of south Florida, in response to client groups that have been tasked with setting performance measures and targets for these key wetland habitats.

The immediate goals of this project are to develop a spatially complete reconstruction of the vegetation and hydrologic history of Everglades marl prairie habitats, to determine the timing of initial marl accumulation, and to improve our understanding of the patterns and causes of historical vegetation change. These data will be critical to improve forecasts of marl prairie response to different restoration scenarios. In subsequent years, we intend to synthesize data from wetland habitats throughout the Everglades and reconstruct vegetation and hydrology for specific time slices (i.e., predrainage Everglades (~AD 1850), early 20th century (~AD 1940), and post-C&SF Project (~AD 1960-1970). These data are needed to validate model estimates of predrainage hydrology and to verify impacts of different hydrologic changes on a range of wetland habitats.

A number of specific "major unanswered questions listed in the DOI Science Plan can be answered by this research. These include the following:

Arthur R. Marshall Loxahatchee NWR Internal Canal Structures

  1. "What hydrologic targets will restore the natural predrainage hydrology? (DOI Science Plan, p. 42)
  2. "What is the ecological response to hydrologic change? (DOI Science Plan, p. 42).

Water Conservation Area 3 Decompartmentalization and Sheetflow Enhancement

  1. "What were the physical and ecological conditions in the Greater Everglades prior to drainage and modification, including physical, chemical, and biological processes responsible for development and persistence of soils and geomorphological patterns in the historical Everglades landscape (DOI Science Plan, p. 71)

Additional Water for Everglades National Park and Biscayne Bay Feasibility Study

  1. "What were the physical and ecological conditions in Shark River and Taylor Sloughs and Biscayne Bay prior to drainage and modification, including historic hydrologic, geologic, ecological, and water quality conditions? (DOI Science Plan, p. 71).

Landscape-Scale Modeling

  1. "What are the physical conditions in the Greater Everglades prior to drainage...? (DOI Plan, p. 92)

Recovery of Vegetative Communities and Multiple Animal Species

  1. "How do we optimize the benefits of restoration for protected avian species in South Florida while minimizing tradeoffs caused by conflicting habitat needs? (DOI Plan, p. 110)

This study supports these CERP projects by 1) conducting research to reconstruct past vegetation and hydrology and understand relative impacts of natural climate variability and human alteration of hydrology on critical habitats; 2) determining the primary external drivers of habitat formation and degradation; 3) providing modelers with data on historic/predrainage conditions to validate model estimates of predrainage hydrology; and 4) providing a predrainage land-cover dataset for use in a range of climate and hydrologic models.

Specific Relevance to USGS Mission:

This project is directly related to two science directions in the USGS Science Strategy (USGS Circ. 1309): 1) Understanding Ecosystems and Predicting Ecosystem Change and 2) Climate Variability and Change. We are investigating the causes and consequences of ecological change over long timescales to understand impacts of natural and anthropogenic changes on the habitats throughout the greater Everglades ecosystem. These techniques are applicable to wetland and other terrestrial habitats throughout the world. This research is aimed at understanding the interactions between biological and nonbiological components of the ecosystem and evaluating consequences of environmental change for different components of the ecosystem. We use results from this research to inform land managers and policy makers on likely response of the greater Everglades wetland to different management and climate scenarios. This investigation contributes to the Climate Variability and Change direction by reconstructing late Holocene climate paleohistory and climate-related ecological, biological, and physical responses. These provide a baseline level of variability for habitats within the ecosystem and provide a basis to forecast impacts of future climate changes on this wetland ecosystem.

Status: In FY11, we conducted fieldwork in current and former Cape Sable Seaside Sparrow (CSSS) habitat. A total of 50 surface samples were collected along vegetation transects established by M. Ross to refine pollen-based interpretation of past vegetation in marl prairie habitats and Shark River Slough. Samples from ten of these sites have processed and four have been analyzed. We also collected nine cores that penetrated to bedrock (~80 cm) in former CSSS habitat. Four cores have been processed and submitted to labs for geochronologic analysis. We completed analysis of pollen on two of these cores. Three cores were collected in WCA3A near water gauge stations. These cores will be analyzed and used in collaboration with F. Marshall in model development to reconstruct past stage and water depth based on pollen evidence. A series of surface samples, as well as several sediment cores from WCA3A and ENP were shared with Robert Booth, Lehigh University, to develop a calibration dataset to infer paleohydrology using testate amoebae analysis. We continued to collaborate with P. Conrads for hydrologic modeling on pollen data and environmental interpretations from 14 sites. Another suite of surface sediments samples from marl prairie core sites were split and sent to J. Sah for carbon isotopic analysis.

Recent Products:

  1. Bernhardt, C.E. and Willard, D.A., 2006. Marl prairie vegetation response to 20th century hydrologic change. U.S. Geological Survey Open-file report 2006-1355.
  2. Willard, D.A., Bernhardt, C.E., and Saunders, C., 2008. Vegetation and hydrologic history of Everglades marl prairies: paleoecological evidence from Big Cypress National Preserve. 2008 GEER Conference.
  3. Willard, D.A., Bernhardt, C.E., and Brandt, L.A., 2008. Response of wetlands in the Arthur R. Marshall Loxahatchee National Wildlife Refuge to hydrologic change: anthropogenic and climate impacts. 2008 GEER conference.
  4. Bernhardt, C.E. 2008. Palynological evidence of anthropogenic activity on tree islands. Greater Everglades Ecosystem Restoration Conference, July 28- August 1, 2008, Naples FL.
  5. Larsen, L., Aumen, N., Bernhardt, C., Engel, V., Givnish, T., Hagerthey, S., Harvey, J., Leonard, L., McVoy, C., Noe, G., Nungesser, M., Rutchey, K., Sklar, F., Troxler, T., Volin, J., and Willard, D., 2008. The Role of Flow and Transport Processes in Ridge/Slough/Tree Island Pattern Dynamics. 2008 GEER conference.
  6. Bernhardt, C.E., and Willard, D.A. 2009. Response of the Everglades ridge and slough landscape to climate variability and 20th- century water management. Ecological Applications 19: 1723-1738.
  7. Willard, D.A. and Bernhardt, C.E., 2009. Natural vs. anthropogenic hydrologic variability in the Florida Everglades: a paleoecological perspective. 2009 National Conference on Ecosystem Restoration.
  8. Larsen, L., Aumen, N., Bernhardt, C., Engel, V., Givnish, T., Hagerthey, S., Harvey, J., Leonard, L., McCormick, P., McVoy, C., Noe, G., Nungesser, M., Rutchey, K., Sklar, F., Troxler, T., Volin, J., and Willard, D., in review, Recent and historic drivers of landscape change in the Everglades ridge, slough, and tree island mosaic. Critical Reviews in Environmental Science and Technology.
  9. Bernhardt, C.E., Brandt, L.A., and Willard, D.A., in prep. Developing sustainable restoration goals in the Everglades wetland: application of paleoecological evidence in Arthur R. Marshall Loxahatchee National Wildlife Refuge. Wetlands.
  10. Presentation to client agencies at GE PES-organized Climate workshop – February 2008: Everglades Wetland Response to Climate Change (Willard)
  11. Presentation to client agencies and colleagues at SFWMD-organized workshop on Ghost Tree Islands, May, 2008: Patterns of Development of Fixed Tree Islands and the Ridge and Slough Landscape (Willard)
  12. Presentation at A.R.M. Loxahatchee National Wildlife Refuge Annual Science Workshop, August, 2009: Response of Arthur R. Marshall Loxahatchee National Wildlife Refuge wetlands to hydrologic changes: anthropogenic and climate impacts (Brandt)
  13. Presentation to Big Cypress Preserve Research Symposium, October 2009: Paleoecology of Deep Lake, Big Cypress National Preserve, Florida (Bernhardt)
  14. Participated in workshop on Past, Present, and Future Climate Change Drivers and Everglades Restoration, organized by Florida Coastal Everglades Long-Term Ecological Research group, October, 2009 (Bernhardt)
  15. Willard, D.A., Bernhardt, C.E., Landacre, B., and Marot, M., 2010. Long-term spatial and temporal heterogeneity within Everglades marl prairies: a late Holocene perspective. 2010 Greater Everglades Ecosystem Restoration Conference
  16. Bernhardt, C.E., and Willard, D.A. 2010. Sensitivity of Everglades wetland communities to hydrologic change. 2010 USGS Climate Change Science conference
  17. Willard, D.A., and Bernhardt, C.E., 2011, Impacts of past climate and sea level change on Everglades wetlands: placing a century of anthropogenic change into a late-Holocene context. Climatic Change, vol. 107, 59-80.
  18. Bernhardt, C.E., 2011. Native Americans, regional drought, and tree island evolution in the Florida Everglades.  The Holocene, vol. 21, 967-978.
  19. Larsen, L., Aumen, N., Bernhardt, C., Engel, V., Givnish, T., Hagerthey, S., Harvey, J., Leonard, L., McCormick, P., McVoy, C., Noe, G., Nungesser, M., Rutchey, K., Sklar, F., Troxler, T., Volin, J.h , Willard, D., 2011. Recent and historic drivers of landscape change in the everglades ridge, Slough, and Tree Island Mosaic. Critical Reviews in Environmental Science and Technology, vol. 21, Issue SUPPL. 1, p. 344-381.
  20. Bernhardt, C.E., Willard, D.A., and Landacre, B., 2011, Marl prairie vegetation response to 20th century land use and its implications for management in the Everglades: NCER pg. 33.
  21. Bernhardt, C.E, Brandt, L.A., Willard, D.A., and Landacre B., 2011, Reconstructing vegetation response to altered hydrology and its use for restoration, Arthur R. Marshall Loxahatchee National Wildlife Refuge, Florida: NCER pg. 43.
  22. Wingard, G.L., Willard, D.A., and Bernhardt, C.E., 2011, Potential impacts of climate change and sea level rise on South Florida's coastal wetlands: NCER pg. 394.
  23. Andrews, T., Booth, R., Bernhardt, C.E., and Willard, D.A., 2011, Testate amoebae as paleohydrological proxies in the Florida Everglades: EOS Trans. AGU Fall meeting supplement
  24. Bernhardt, C.E., and Willard, D.A., 2012, Climate and vegetation history of current and former Cape Sable Seaside Sparrow wetland habitat, Florida Everglades: Submitted to INTECOL 2012

Planned Products:

  1. Journal article on vegetation response in Loxahatchee NWR: Bernhardt, Brandt, Willard
  2. Report/journal article on carbon isotopic patterns from Everglades marl prairie habitats: Sah, Ross
  3. Synthesis of paleovegetational and paleohydrologic data from >75 sites in greater Everglades ecosystem
  4. USGS Open File Report on ecosystem history patterns from marl prairie habitats

WORK PLAN

Title of Task 1: Impacts of Hydrologic and Climatic Change on Greater Everglades Marl Prairies, Marshes, and Sloughs
Task Funding: USGS Priority Ecosystems Science
Task Leaders: D.A. Willard
Phone: 703-648-5320
FAX: 703-648-6953
Task Status (proposed or active): Active
Task priority: High
Time Frame for Task 1: FY07; FY08, FY09; FY10; FY11; FY12
Task Personnel: C. Bernhardt, B. Landacre, J. Sah, T. Sheehan, M. Marot, D. Willard

Task Summary and Objectives:

The initial objective of this project is reconstruction of marl prairie vegetation and hydroperiod for the last few centuries to evaluate impacts of climate variability and anthropogenic alteration of hydrology on this critical habitat. This research builds upon previous work throughout the Greater Everglades wetland that documents responses of tree islands and the ridge and slough landscape to natural and anthropogenic hydrologic change (completed 2007). This task requires: 1) multi-proxy analyses (pollen, charcoal, carbon isotopes, geochronology) of sediment cores from marl prairie habitats; and 2) refinements to the existing Everglades pollen calibration dataset by collecting and analyzing surface samples along vegetation transects established by M. Ross and colleagues at Florida International University. An additional objective of the project is refinement of down-core estimates of hydroperiod and stage by calibrating results from new and existing cores with nearby stream gage records. For this task, fine sampling of several new cores will be paired with stream gages with the longest records to calibrate pollen-based estimates of hydroperiod using instrumental records. The resulting refinements will be used to re-evaluate paleohydrologic evidence from ~75 existing sites and develop an Everglades-wide hydrologic reconstruction for pre- and post-drainage time slices. Proxy records preserved in Everglades sediments provide an archive of wetland response to a series of natural and anthropogenic hydrologic experiments during the last few millennia and document the impacts of multidecadal climate processes on wetland communities. By extending the period of record of observations in this "living laboratory of change, these data improve our ability to forecast future ecosystem response to a broad range of climate and management scenarios.

Work to be undertaken during the proposal year and a description of the methods and procedures:

Six cores collected in former CSSS habitat will be processed and analyzed for pollen and microscopic charcoal. Age models based on radiocarbon dates, short-lived radioisotopes (210Pb and 137Cs), and pollen biostratigraphy will be generated for each core. These cores will be used to determine vegetation and hydrologic characteristics associated with CSSS occupation and abandonment. Pollen and charcoal analysis will be completed on two sediment cores that are co-located with stream gages in consultation with P. Conrads and F. Marshall for model calibration studies. We will integrate pollen analysis of sediment cores collected in Taylor and Shark River Sloughs with model efforts to develop a statistical method to infer past hydroperiods from down-core pollen assemblages. Stable carbon isotopes will be analyzed from at least three sediment cores, determined in consultation with colleagues. Pending results of testate amoebae calibration study, we anticipate their analysis from at least one core to develop independent paleohydrologic reconstruction. Other previously collected cores will be described, photographed, and sectioned for future analyses. A USGS Open-File Report will be prepared summarizing results from the marl prairie sediment cores.

Work to be undertaken in future years:

Specific Task Product(s):

  1. Journal article on vegetation response in Loxahatchee NWR: Bernhardt, Brandt, Willard
  2. Report/journal article on carbon isotopic patterns from Everglades marl prairie habitats: Sah, Ross
  3. Synthesis of paleovegetational and paleohydrologic data from >75 sites in greater Everglades ecosystem
  4. USGS Open File Report on ecosystem history patterns from marl prairie habitats