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Project Work Plan
Department of Interior USGS GE PES
Fiscal Year 2010 Study Work Plan
Study Title: Determining Target Salinity Values for Restoration of the Estuaries of the Greater Everglades
Overview & Objective(s): The primary objective of this project will be to provide information to CERP managers that can be used to establish target salinity values and performance measures for the estuaries and coastal ecosystems, and to estimate the freshwater stage and flow in the wetlands required to produce historical salinity patterns. This work will build upon previous work in Florida Bay and Biscayne Bay, and information derived from the Ecosystem History Synthesis Project (completed 2007). There are four areas of focus for this task. 1) Refine our existing modern analog data set by completing analyses of modern samples collected between 1996 and 2004, obtaining additional modern samples where necessary, and applying these improved analog data to core data compiled in the Ecosystem History Synthesis Project. 2) Collect new cores (if necessary) or examine existing archived cores within the southern estuaries to fill in information gaps identified by the land management agencies (Everglades National Park (ENP) and Biscayne National Park (BNP)), and by the Southern Coastal Systems Subteam of the Regional Evaluation Team (RET) of RECOVER. 3) Work with our collaborator, Dr. Frank Marshall, to analyze the paleoecology data with linear regression models that can hindcast stage, flow and hydropatterns in the terrestrial Everglades, and salinity in the estuaries, based on equations developed from existing data. These efforts, when combined with our new study beginning in FY10 to examine sea level history, will ultimately lead to the ability to forecast future changes and develop salinity targets for estuaries for the CERP 2050 Plan that incorporate natural hydrologic relationships and sea level rise, and take into account future altered conditions under various IPCC scenarios. These data can be used to help select minimum flows and levels for the wetlands. The estuaries of South Florida are not only a "living laboratory of change" but they provide the record of past changes that allow us to forecast the direction of future change.
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 a number of documents. The DOI Science Plan lists as one of the three primary restoration activities the need to "ensure that hydrologic performance targets accurately reflect the natural predrainage hydrology and ecology" (DOI Science Plan, p. 14). The USGS Science Plan for south Florida (2003 draft, msp. 7) identifies five primary science goals, the second of which is to "determine the historical ecological setting of the Everglades." The primary goal of this project, and related previous ecosystem history projects, is to determine the predrainage hydrology and ecology of critical regions within the estuaries and coastal ecosystems of south Florida, identified by the Southern Coastal Systems Subteam and other client groups, which have been tasked with setting performance measures and targets for these coastal zones.
This project specifically addresses the needs identified by the Southern Coastal Systems Subteam of the Regional Evaluation Team (RET) of RECOVER. The Subteam is tasked with establishing performance measures and salinity targets for the estuaries and initially the intent was to use the Natural Systems Model (NSM) as the primary basis for the target values. In spring 2005, however, the Subteam ran simulations using the NSM for the Initial CERP Update (ICU) that returned salinity values far in excess of any anticipated. They therefore determined that the NSM was not a reliable indicator of near shore salinity patterns, and they have indicated a desire to rely on paleosalinity data to establish targets and performance measures. Coverage of cores in southern Biscayne Bay and northern Florida Bay is limited, however, with each basin having characteristic patterns. This project builds upon earlier projects and fills in information gaps identified by the Southern Coastal Systems Subteam for Florida Bay, Biscayne Bay, and potentially parts of the southwest coastal area.
While the primary goal of this project is to provide data to assist in the establishment of sustainable salinity targets and performance measures, this project also addresses a number of other restoration needs identified in the RFP. The data we gather can be used by the Biscayne Bay Coastal Wetlands Project to assist in developing minimum flows and levels. Our data on the biota present over time and their changes in response to changing water conditions can be used to address questions about natural habitats including the following: 1) the impact of existing and proposed freshwater flows on coastal communities; 2) responses of native organisms to the introduction of exotic species. We will examine the role of climate and sea level rise on changing salinity patterns in the coastal communities, how these natural changes have been over-printed by anthropogenic change, and how sea level and climate should be factored into restoration targets.
A number of specific "major unanswered questions" asked in the DOI Science Plan can be answered by this research. These include the following:
Florida Bay and Florida Keys Feasibility Study
This study supports these CERP projects by 1) conducting research to understand the predrainage hydrology, including the amount, timing and seasonality of freshwater delivered to the estuaries historically; 2) examining the historical environmental conditions, including the linkage between hydrology (water quality and quantity), ecology, and habitats; 3) providing modelers with data on historic conditions in order to set targets and performance measures that reflect natural hydrologic patterns; and 4) providing long-term historical data on trends and cycles within the biological component of the ecosystem that can be forecasted to predict the effects of implementation of hydrologic restoration on the ecology of coastal communities.
Specific Relevance to USGS Mission:
This project is directly related to the USGS Science Strategy (USGS Circ. 1309) - Understanding Ecosystems and Predicting Ecosystem Change. We are investigating the causes and consequences of ecological change and are developing and providing methods for protecting and managing the South Florida Ecosystem - methods which can be applied to other ecosystems around the country and around the world. We are interpreting for the land managers and policy makers how current and future rates of change will affect the natural resources and societal infrastructure of South Florida. In addition, the project contributes significantly to the Climate Variability and Change Science Strategy by examining the effects of climate and sea level rise on the South Florida ecosystem over historically significant time periods. Using historical records, we can project future states under various IPCC scenarios and how those scenarios may affect restoration planning.
Status: In FY09, the molluscan analog data set CWP method was utilized in the Linear Regression Models for two cores and produced comparable results to those achieved in FY08. We also have continued to refine the modern proxy data set with additional information from low salinity regimes in the Shark River Slough area, and we have begun to map out a key assemblage that may serve as an important indicator and monitoring tool for restoration. Our manuscript on the coupled paleoecologic data and linear regression models was published in FY09, and a manuscript on the Cumulative Weighted Percent Method will be in review in early FY10. An overview of the salinity history of the Southern Estuaries will be a case study chapter in a Springer Series: Developments in Paleoenvironmental Research: Palaeoestuarine Studies. New linear regression equations were developed for the Rankin Basin area, and for more central locations in Florida Bay around Bob Allen and Russell Bank. These equation sets improved or upgraded the existing system of models that were developed for evaluating the pre-drainage hydrology using the Whipray Basin sediment core in FY08. The improved system of models have been used to develop two additional estimates for the pre-drainage hydrology (stage and flow in the Everglades, salinity in Florida Bay) by coupling the CWP faunal derived paleosalinity with the models. Rankin Basin model output was completed in FY09 and Russell Bank will be completed by the end of FY09. In addition, a second calculation was run on Whipray (analyzed in FY08) utilizing the CWP to compare output from CWP versus assemblage analysis. The results were similar, but the CWP output can be used in a Bay-wide comparison to Rankin, Russell, etc.
Title of Task 1:
Determining Target Salinity Values for Restoration of the Estuaries of the
Task Summary and Objectives:
The purpose of this task is to compile and consolidate all existing information on paleosalinity and provide this information to the Southern Coastal Systems Subteam of the Regional Evaluation Team (RET) of RECOVER to assist them in developing interim salinity targets for restoration. Working with the sub-team, we will identify any existing data gaps that need to be filled. There are three specific objectives for this task. 1) Refine our existing modern analog data set by completing analyses of modern samples collected between 1996 and 2004 and applying these improved analog data to core data compiled in the Synthesis Project. 2) Collect new cores (if necessary) or examine existing archived cores within the southern estuaries to fill in information gaps identified by the land management agencies (Everglades National Park (ENP) and Biscayne National Park (BNP)), and by the Southern Coastal Systems Subteam of the Regional Evaluation Team (RET) of RECOVER. 3) Work with our collaborators to plug all of the combined paleoecology data into linear regression models that can hindcast salinity for different parts of the system and estimate the wetlands stage and flow required to produce those salinities. Ultimately we hope to forecast these data in combination with the results from task 2, to give a picture of realistic CERP 2050 salinity targets.
Work to be undertaken during the proposal year and a description of the methods and procedures:
We will continue in FY10 to provide information on flow, stage and salinity for the pre-drainage Everglades to the Southern Coastal Systems subteam of RECOVER. We will utilize the models developed by Dr. Frank Marshall (contractor, Cetacean Logic Foundation) coupled with paleoecologic data from USGS cores. At least two additional cores from Florida Bay will be analyzed in FY10. (Individual reports will release the core data.) Our plan is to complete work on Florida Bay, and to develop a "consensus" pre-drainage hydrologic regime for Florida Bay. This information will be presented orally and/or in report form to the Southern Coastal Systems subteam of RECOVER. In addition, we will compile the information for a manuscript on the pre-drainage hydrology of Florida Bay for submission to a peer-reviewed journal. Work will expand in FY10 from Florida Bay to begin applying the coupled paleoecology - linear regression models to cores from Southwest Coastal area (Shark River Slough Transect). At least one core from this area will be incorporated into the linear regression models in FY10.
Additionally, improvements to our modern analog data set will continue. We will identify/refine the modern ecologic constraints for a few key species found in the cores. A faunal/floral association found in the southwest coastal area will be investigated as potential indicators for the critical freshwater/estuarine transition zone. This work will be conducted in conjunction with Impacts of Hydrologic and Climatic Change on Greater Everglades Marl Prairies, Marshes, and Sloughs (Willard, PI).
Work to be undertaken in future years:
FY2011 efforts will be focused on synthesizing the paleosalinity data on all of south Florida's estuaries to develop a regional overview of the changes that have occurred in the Southern Coastal Systems. These data will include the faunal and floral analyses that have been conducted over the years, as well as the linear regression models developed by Frank Marshall. By including Frank Marshall's models, we are able to estimate the freshwater stage and flow in the wetlands required to produce the paleosalinities derived from the biotic analyses.
Specific Task Product(s):
U.S. Department of the Interior, U.S. Geological Survey
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Last updated: 04 September, 2013 @ 02:09 PM(KP)