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projects > effect of sheet flow on transport of suspended particles, and particle-associated nutrients in the everglades ridge and slough landscape > work plan

Project Work Plan

U.S. Geological Survey, Greater Everglades Priority Ecosystems Science (GE PES)

Fiscal Year 2007 Study Work Plan

Study Title: Effect of Sheet Flow on Transport of Suspended Particles, and Particle-Associated Nutrients in the Everglades Ridge and Slough Landscape
Study Start Date: October 2003 Study End Date: To Be Determined, September 2007 to September 2010
Web Sites: http://water.usgs.gov/nrp/jharvey/sfstpt/; http://sofia.usgs.gov/projects/susparticles/; http://sofia.usgs.gov/projects/wtr_flux/; http://sofia.usgs.gov/sfrsf/entdisplays/waterlevels/; http://sofia.usgs.gov/exchange/harvey/harveyDATA.html; http://water.usgs.gov/nrp/jharvey/site/index.html
Location (Subregions, Counties, Park or Refuge): Northern, Central, and Southern Everglades (Palm Beach, Broward, Miami-Dade)
Funding Source: USGS Greater Everglades Priority Ecosystems Science (GE PES)
Other Complementary Funding Source(s): None
Funding History: FY04; FY05; FY06
Principal Investigator(s): Jud Harvey (USGS, Reston), Greg Noe (USGS, Reston), and Ray Schaffranek (USGS, Reston)
Study Personnel: Ben O'Connor (NRC postdoc), Dan Nowacki (USGS ), Leanna Westfall (ECO), and Laurel Larsen (Ph.D. student)
Supporting Organizations: USGS, SFWMD, NPS/Everglades National Park
Associated / Linked Studies:
Tides and Inflows at the Mangrove Ecotone (TIME): http://time.er.usgs.gov/;
Integrated Geochemical Studies in the Everglades: http://sofia.usgs.gov/projects/wetland_seds/, http://sofia.usgs.gov/projects/evergl_merc/;
Freshwater Flows into Florida Bay: http://sflwww.er.usgs.gov/projects/freshwtr_flow/;
Florida Coastal Everglades Long-Term Ecological Research: http://fcelter.fiu.edu/

Overview & Objective(s):
A primary directive in the Comprehensive Everglades Restoration Plan (CERP) is to restore Everglades hydrology toward pre-drainage conditions in a manner that will successfully restore landscape structure and function while protecting water quality. Central to CERP is the Water Conservation Area 3 Decompartmentalization & Sheet Flow Enhancement project (DECOMP) which has the objective to restore sheet flow and hydrologic connectivity in much of the Everglades. DECOMP is intended to reverse the management policies that in the past led to loss of diversity in Everglades landscape patterns (i.e., losses of ridge and slough and tree island topographic features and associated losses of diversity in flora and fauna). Increasing numbers of scientists and stakeholders believe that sheet flow and sediment transport processes are a key aspect of Everglades landscape function and a key uncertainty in the restoration (Harvey and Sklar, 2006). The National Park Service (Crisfield and McVoy, 2004), National Research Council (National Research Council, 2003), and the Department of Interior (DOI, 2005) have all recommended research to determine how changing the amount and distribution sheet flow in a “restored” Everglades will influence landscape characteristics. A growing concern is that augmenting sheet flow to benefit the hydrology of certain downstream areas could have unintended consequences to other areas, such as transporting surface-water contaminants farther into the central and southern parts of the Everglades ecosystem than ever before. Our study is necessary to identify the critical hydrologic, chemical, and biologic linkages that have shaped both the pre-drainage Everglades and the current landscape. As part of that research we will quantify the fundamental processes that determine how much farther downstream suspended sediments and associated nutrients will be transported as a result of increased sheet flow velocities. This information is necessary for understanding the critical factors that sustain the ridge and slough landscape structure and ecosystem function, and is also necessary for predicting some of the unintended side-effects of restoration activities that may accompany increases in flow and hydrologic connectivity. Our ultimate goal is to meet the Science Coordination team's challenge (SCT, 2003) of ensuring the level of scientific readiness needed to protect both Everglades landscape conditions and water quality though adaptive management of “restored” flows. Important scientific questions being addressed are:

  • How do the characteristic ridge and slough topographic variation and its associated vegetation patterns influence the sources, transport rates, and rates of interception of suspended particulates and nutrients?
  • What are relative roles of transport of fine suspended particulate matter and coarser flocculent benthic organic matter (floc) in suspended sediment and phosphorus budgets in Everglades wetlands?
  • To what extent will sources, concentrations, and transport distances of suspended sediments and nutrients in Everglades wetlands be altered by DECOMP? Will it be the increased sheet flow velocities or the extent that canals are backfilled after levee removal that will be the more important driver of changes in transport?

Specific Relevance to Major Unanswered Questions and Identified Information Needs:

Our proposed experiments and modeling are fundamental to building a reliable predictive capability of how the Everglades will respond to the restoration's higher flows. The multi-agency Science Coordination Team of the South Florida Ecosystem Restoration Task Force (http://www.sfrestore.org/) asserted the need for research on interactions between flow and ecological processes in the Everglades (Science Coordination Team, 2003). Furthermore, the National Research Council reports a lack of understanding of the role of flow as a factor contributing to landscape changes in the Everglades (National Research Council, 2003). The Monitoring and Assessment Plan (MAP) of the Comprehensive Everglades Restoration Plan (CERP) (http://www.evergladesplan.org) also calls for the need of background information on sheet flow behavior for effective restoration assessment. The need for investigations of interactions between flow and water quality is also identified as needed priority research in multiple sections of the Science Plan of the Department of Interior (2005). The research also follows the DOI Science plan's main recommendation by directly addressing the following CERP Interim Goals (3.2-Sheet Flow in Natural Areas, 3.3-Hydropattern, 3.5-Everglades Wetlands Total Phosphorus, and 3.7-Ridge and Slough Pattern).The proposed combination of empirical and modeling research supports several of the critical information needs identified by the National Academy of Science and DOI's Science Plan. For example, the National Academy of Sciences has emphasized the importance of sediment transport to understanding and restoring the Everglades (NRC, 2003), while the DOI Science Plan highlights the need to understand the influence of hydrology on nutrient and contaminant transport and cycling (U.S. Department of the Interior, 2005). While our proposed work addresses fundamental questions that are relevant to management questions throughout the Everglades, at the same time it also addresses key site-specific CERP projects mentioned in the DOI Science plan. These critical CERP projects include the WCA-3A Decompartmentalization (DECOMP) Project, and Tamiami Trail Bridge Expansion projects, in addition to broader projects related to preservation of landscape structure (e.g. Landscape-Scale Modeling Study and Ridge and Slough Performance Standards), and changing water quality and the need for more modern water-quality performance standards in the Everglades (e.g. Comprehensive Integrated Water Quality Feasibility Study). Finally, the information gained on suspended sediment and nutrient transport will aid critical modeling efforts that support the Loxahatchee Internal Canal Structures Project. In conclusion, our proposed work supports no less than six of the key projects identified by DOI as critical to the success of the Everglades restoration.

Summary of Research Progress FY03 - FY06
The central objective of our research has been to determine the role of transport of suspended particles in controlling storage, transport, and transformation of associated nutrients in the surface water of Everglades wetlands. Preliminary transport experiments that were conducted in the first year of the investigation highlighted the potential for differential transport characteristics of particles and solutes (Saiers and others, 2003; Harvey and others, 2005). In the second year, the physical and biogeochemical characteristics of fine suspended particles were measured across regional and phosphorus enrichment gradients in the Everglades (Noe and others, in press). In the third year (FY06) we investigated in detail the interactions between phosphorus biogeochemistry, particle transport and filtration, and water flow velocity. The site chosen for monitoring and experimentation was in northern Water Conservation Area 3A in an area of relatively well-preserved ridge and slough topography. Two adjacent monitoring sites were established (one on the ridge and one in the slough) where water depth, velocity, specific conductivity, and temperature profiles in the water column were measured continuously. Dissolved and suspended fine particulate concentrations (including organic and inorganic forms of particle associated nutrients) were measured at three depths in the water column and seven depths in pore water once per month. At the same sites our group measured detailed topography and microtopography, vegetation, and sediment characteristics at the ridge and slough sites and at transition sites between them. One sampling trip was devoted to measuring storage of nutrients in different chemical phases in soil, soil porewater, and plants at eight sites across the ridge to slough transition. A controlled set of tracer injections using both solute tracers and “model” particles (1-um fluorescent latex spheres) were also undertaken in FY06, with the purpose to investigate the interactions between phosphorus biogeochemistry, fine suspended particle transport, and variable water flow velocities. The goal was to determine in detail the fate of solutes and fine particulate matter under different flow conditions and to identify the specific physical and biological features and processes responsible for the observed levels of transport and storage. Modeling by our group is underway to interpret the controlling processes, such as particle sources, size classes, and phosphorus content; transport and filtration rates of particles; water flow velocity and shear stress as they differ within ridge and slough plant communities; and chemical reactions that phosphorus undergoes in its various dissolved and particulate forms. This information is critical for improving the modeling of the cycling and transport of dissolved and particulate contaminants in the Everglades.

Selected Findings to Date:

* Sheet flow velocities ranged between 0.08 and 0.55 cm/s at site WCA-3A-5, which is lower than velocities measured in (1999 - 2003) in Shark Slough (0.46 to 2.29 cm/s). * Mean flow velocity in the slough was typically 34% faster, water depth was typically 20 cm greater, and average time period of surface-water inundation was approximately 20% longer compared with the ridge. * In both ridge and slough the average suspended particulate concentrations were relatively low (0.5 - 3 mg/L), and average particle size was approximately 10 um. * Particulate phosphorus tended to be associated with relatively small particles (1 um), while particulate nitrogen tended to be associated with particles of intermediate size (6 um). * The mass transport of water and suspended particulates was, on an average annual basis, approximately twice as high in the slough as it was on the ridge. * Particle capture by vegetation was more effective in the ridge than in the slough (greater than 80% of tracer particles were removed over a 30-m flow path on the ridge). * Maximum flow velocities were an order of magnitude greater during Hurricane Wilma, and velocities quickly returned to typical sheet flow conditions after hurricane passage.

Products of the USGS Sheetflow and Sediment Transport Processes Team: 2003 - 2006:

Davis, S.E. III, Childers, D.L., and Noe, G.B. 2006. The contribution of leaching to the rapid release of nutrients and carbon in the early decay of oligotrophic wetland vegetation. Hydrobiologia 569: 87-97.

Gaiser, E. E., Trexler, J., Richards, J., Childers, D., Lee, D., Edwards, A.L., Scinto, L., Jayachandran, K., Noe, G., and Jones, R. 2005. Cascading ecological effects of low-level phosphorus enrichment in the Florida Everglades. Journal of Environmental Quality 34: 717-723.

Harvey, J.W., Krupa, S.L., and Krest, J.M. 2004. Ground water recharge and discharge in the central Everglades. Ground Water 42(7):1090-1102.

Harvey, J.W., Newlin, J.T., and Krest, J.M., Choi, J., Nemeth, E.A., and Krupa, S.L. 2005. Surface water and ground water interactions in Water Conservation Area 2A, Central Everglades. USGS Scientific Investigations Report 2004-5069. 88p.

Harvey, J.W., Newlin, J.T., and Krupa, S.L. 2006. Modeling decadal timescale interactions between surface water and ground water in the central Everglades, Florida, USA. Journal of Hydrology 320: 400-420.

Harvey, J.W., Saiers, J.E., and Newlin, J.T. 2005. Solute transport and storage mechanisms in wetlands of the Everglades, South Florida. Water Resources Research, 41, W05009, doi:10.129/2004WR003507.

Harvey, J.W., Noe, G.B., Schaffranek, R.W., Saiers, J.E., Huang, Y.H., and Larsen, L.G. 2006. Understanding linkages between sheet flow and suspended sediment transport processes in the ridge and slough landscape. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 92.

Harvey, J.W. and Sklar, F. 2006. WORKSHOP: Development of a Conceptual Model for Ridge and Slough Landscape Dynamics. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 91.

Huang, Y.H., Saiers, J.E., Harvey, J.W., and Noe, G.B. 2006. Particle transport through surface waters of the Florida Everglades. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 99.

Larsen, L.G., and Harvey, J.W. 2006. Feedbacks between differential peat accretion and anabranching river mechanics in the ridge and slough landscape. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 128.

Noe, G.B., Scinto, L.J., Taylor, J., Childers, D.L., and Jones, R.D. 2003. Phosphorus cycling and partitioning in an oligotrophic Everglades wetland ecosystem: a radioisotope tracing study. Freshwater Biology 48(11):1993-2008.

Noe, G.B., Harvey, J.W., Schaffranek, R.W., Saiers, J.E., and Larsen, L.G. 2006. Spatiotemporal variation in the characteristics of suspended particles in the Everglades: implications for the ridge and slough landscape. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 158.

Noe, G.B., Harvey, J.W., and Saiers, J.E. In press. Characterization of suspended particles in Everglades wetlands. Limnology & Oceanography.

Noe, G.B., and Childers, D.L. In press. Phosphorus budgets in Everglades wetland ecosystems: The effects of hydrology and nutrient enrichment. Wetlands Ecology and Management.

Saiers, J.E., Harvey, J.W., and Mylon, S.E. 2003. Surface-water transport of suspended matter through wetland vegetation of the Florida Everglades. Geophysical Research Letters 30(19), 1987, doi:10.1029/2003GL018132.

Schaffranek, R.W. 2004. Sheet-flow velocities and factors affecting sheet-flow behavior of importance to restoration of the Florida Everglades, U.S. Geological Survey Fact Sheet 2004-3123, 4 p. http://pubs.er.usgs.gov/pubs/fs/fs20043123

Schaffranek, R.W., Harvey, J.W., Noe, G.B., Riscassi, A.L., Nowacki, D.J., and Larsen, L.G. 2006. Sheet flow in the ridge and slough landscape of Everglades Water Conservation Area 3A, Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p.197.

Schaffranek, R.W., and Riscassi, A.L. 2004. Flow velocity, water temperature, and conductivity at selected locations in Shark River Slough, Everglades National Park, Florida: July 1999-July 2003, U.S. Geological Survey Data Series 110. http://pubs.water.usgs.gov/ds110/

Schaffranek, R.W., Riscassi, A.L., and Nowacki, D.J. 2006. Flow simulation in Everglades National Park, Third Federal Interagency Hydrologic Modeling Conf., April 2-6, 2006, Reno, NV, 8 p.

Schaffranek, R.W., and Riscassi, A.L. 2004. Flow velocity, water temperature, and conductivity at selected locations in Shark River Slough, Everglades National Park, Florida: July 1999-July 2003, U.S. Geological Survey Data Series 110. http://pubs.water.usgs.gov/ds110/.

WORK PLAN

Title of Task 1: Effect of Water Flow on Transport of Solutes, Suspended Particles, and Particle-Associated Nutrients in the Everglades
Task Funding: USGS Priority Ecosystems Science
Task Leaders: Jud Harvey, Greg Noe, Ray Schaffranek
Phone: (703) 648-5876
FAX: (703) 648-5484
Task Status (proposed or active): Active
Task priority: High
Time Frame for Task 1: October 2006 - TBD, September 2007- September 2010
Task Personnel: Ben O'Connor, Dan Nowacki, Leanna Westfall, Laurel Larsen
Task Summary and Objectives: See Overview and Objectives above

The Science Coordination Team (2003) and National Research Council (2003) have strongly recommended that research be undertaken to better understand the processes controlling the origin and maintenance of the ridge and slough landscape of the central Everglades. The high pattern complexity and variability of water depth in the remaining areas of intact ridge and slough is a characteristic feature of the pre-drainage Everglades that is thought to have been important in supporting a high biodiversity of unique assemblages of plants and organisms. The present distribution of ridge and slough habitats indicates substantial areas of degradation, especially in the northern and eastern marginal areas of the Everglades. Degradation is thought to have been brought about through a complex set of processes during the past century as a result of water management practices that emphasized flood control and water storage rather than protection of ecosystem characteristics and function. Two of the important drivers that are hypothesized to be at the root of landscape change were the slowing of sheetflow velocities, and excessive levels of nutrients in runoff from outside entering the Everglades by canal inputs.

Methods to quantify sheetflow velocities in the Everglades using acoustic Doppler methods have only recently been made reliable and have demonstrated the relatively low velocities that now characterize even the areas of relatively well preserved ridge and slough characteristics (Shaffranek and others, 2004). Excessive phosphorus is now stored within the soils of certain “hotspots” near the canals that have been the principal conduits for water and excessive levels of dissolved constituents, including nutrients. Recent estimates suggest that the movement of phosphorus from those storage locations in soil hotspots back into the flowing surface waters now exceeds the inputs of “new” phosphorus from outside the system (Noe and Childers, in press). Noe and others (2003) first identified the strong association between suspended particles in the water column and phosphorus cycling in Everglades wetlands. Hydrologic tracer experiments recently quanitified transport rates of solutes and suspended particles in the Everglades (Saiers and others, 2003, Harvey and others, 2005), and demonstrated that certain subsets of the native Everglades plant communities exhibit very high retention rates by storing solutes and intercepting suspended particulates. However, very little is known at present about how quickly solutes and suspended particulates could spread to downstream areas under the restoration's goal of restored sheetflow velocities.

The Sheetflow and Sediment Transport Processes project of the U.S. Geological Survey is a combined effort of the hydrology, transport processes, and biogeochemical research of Harvey, Noe, and Shaffranek. Our study is identifying the critical hydrologic, chemical, and biologic linkages that have shaped both the pre-drainage Everglades and the current landscape. This information is necessary for understanding the critical factors that sustain the ridge and slough landscape and ecosystem function, and is also necessary for predicting some of the unintended side-effects of restoration activities that may accompany increases in flow and hydrologic connectivity.

The main goal of our group is to identify and quantify critical interactions between sheetflow velocities, transport of suspended sediment and associated nutrients, and their cascading effects on downstream water quality and ecosystem-level responses to restored flow patterns. Our investigations of “reference” conditions at our WCA-3A-5 site in northern WCA-3A will be extended in future years by adding a “first response” research site in WCA-3B, where we will have the ability to test our predictions within the framework of DPM's landscape-scale manipulation of sheet flow in an area of degraded landscape characteristics. The products will be in the forms of interpretive reports, data sets, and modeling parameters that will guide the improvement of water flow models, constituent transport models, and water quality models that will in the future be used to adaptively manage the restoration.

All of our investigations are planned in a way that will maximize support of the critical science needs for the following four projects in the DOI Everglades Science Plan: (1) Water Conservation Area 3 Decompartmentalization and Sheetflow Enhancement, (2) Arthur R. Marshall Loxahatchee NWR (WCA-1) Internal Canal Structures, (3) Comprehensive Integrated Water Quality Feasibility Study, and (4) Landscape-Scale Modeling Study. A noteworthy new development in 2006 was the South Florida Water Management District's and U.S. Army Corps of Engineers' recognition that a physical model is needed to help adaptively guide DECOMP. The DECOMP Physical Model (DPM) is a 5-year landscape-scale experiment that will test the interactions between increased sheetflow, sediment and nutrient transport, and response of downstream biogeochemistry and emergent plant and fish communities. Over the past six months our USGS Sheetflow and Sediment Transport Processes Team has actively contributed to SFWMD's and USACE's DPM design.

The key question we will address in the FY07 experiments is “how do sources, characteristics, rates of transport, and entrainment of organic particles (and associated nutrients) vary with sheetflow velocity and flow environment (ridge or slough)”. The relative importance of fine suspended particles versus coarser flocculent benthic organic particles (floc) to material transport and redistribution under different flow conditions is a key issue for understanding the historic Everglades and planning restoration. Floc stores a much larger mass of sediment and phosphorus than suspended fine particles (Noe and Childers, in press), and therefore could play a larger role in downstream and ridge-slough transport … if it moves. However, very little is known about the transport characteristics of floc.

We will build upon our previous experimentation in particle and solute tracer injections under differing flow conditions in the Everglades. Our previous experiments have helped us develop the experimental design (induced flow in flumes 1-m wide by 10-m long, tracer injection methods, and particle characterization methods) that will make experimentation possible across a range of flow conditions (0.5-5 cm per second) that represent the range of conditions across pre-drainage and modern flow conditions, as well as future scenarios brought about by DECOMP. The most important improvement in the planned experiments is the use of labeled natural suspended particulates rather than the fluorescent or mineral “model” particles that we introduced in previous year's experiments. Use of natural particles in these experiments is essential to reliably characterize “entrainment” of suspended particulates under the naturally complex conditions of mixed particle sizes that arise from several different sources of organic matter (e.g., fine suspended vs. coarse floc). Of particular importance is determining the threshold conditions of sheetflow velocity and bed shear stress that cause entrainment of floc, and determining whether and under what flow conditions those particles will experience a net redistribution from slough to ridge. In addition to measuring changes in suspended sediment concentrations and flux across the experimental flow velocities, we will also quantify the forms of phosphorus associated with fine suspended particles and floc through sequential chemical extractions. Understanding the quality of entrained sediment is necessary to predict its fate at downstream locations of retention. These questions are fundamental to levee-gap design and need for canal backfilling that will allow DECOMP to move forward and be adaptively managed.

We will also continue to investigate interactions between topography, flow velocity, vegetation type and density, and the transport of fine suspended particulates and associated phosphorus at WCA-3A-5. The adjacent ridge and slough sites will be instrumented for continuous measurement of water depth, velocity, specific conductivity, and temperature profiles in the water column. On an occasional basis through the wet season we will measure dissolved and suspended fine particulate concentrations of phosphorus and nitrogen (organic and inorganic forms) at three depths of the water column in both ridge and slough. Dissolved and particulate organic carbon, calcium, iron, aluminum, chloride, bromide, and sulfate will also be measured at the same locations. Dissolved concentrations will also be determined at six depths in pore water of the Everglades peat soil. Estimates of downstream flux of water and dissolved and particulate material will be refined and updated from our FY06 flux estimates. In addition, the forms of phosphorus associated with suspended particles as identified by sequential chemical extraction of captured particles, a method we employed in FY06, will be repeated at the peak of the wet season. Finally, we will test a new technology for continuously measuring in situ particle size distribution and abundance. A Sequoia Scientific LISST-100X laser diffraction particle size analyzer will be deployed for short intervals and calibrated with concurrent particle sampling. If this technology proves valuable in the Everglades, we will deploy the instrument for longer deployments in multiple flow environments. This will provide a valuable test of this technology for potential deployment as part of the DPM and DECOMP.

Modeling will be used to interpret the results of tracer experiments, with the goal to produce a fundamental set of transport parameters representing the role of fine suspended particles, floc, and storage of water and solutes in relatively slow-moving areas of thick vegetation and subsurface pore water. Eventually we expect that our modeling concepts and parameter sets will be implemented in the more comprehensive water-quality models and landscape ecosystem models (such as DMSTA, ELM, and TIME) that are being used to adaptively guide the restoration. In this way the knowledge gained from our detailed experiments will be “scaled-up” for application at larger spatial scales and at longer temporal scales. If successful, we envision the incorporation of our parameters into model applications throughout the Everglades.

If ridge and slough landscape features are to be optimally restored and conserved by restoration, continued research is needed at both “remnant” and “degraded” sites, and experimental approaches must be used to test hypotheses across the gradients in hydrologic connectivity and differing degrees of topographic degradation and eutrophication that currently exist in the central Everglades. Site WCA-3A-5 is an excellent “reference” site for measuring transport rates and processes in remnant conditions where ridge and slough topography is relatively well preserved. This is enabling research designed to understand the flow-topography-sediment interactions that occurred in the historic flow regime and topography of the Everglades. Among our accomplishments is developing the techniques that will be applied in the near future to characterize flow and transport conditions in areas possessing more degraded landscape characteristics.

If our PES study is extended beyond FY'07 we plan to seek from sources the additional funding beyond the PES base funding that will be needed to add a “first restoration response site”. That site will possess substantially degraded ridge and slough topography and will be located downstream of where substantial levee removal is expected to take place (i.e., WCA-3B). Preliminary planning is already underway for the Decompartmentalization Physical Model (DPM), a long-term, landscape-scale experiment. The South Florida Water Management District (SFWMD) and the Army Corps of Engineers (ACE) are taking the lead in planning DPM with Florida International University (FIU) and U.S. Geological Survey (USGS) participating as research partners. The overall purpose of DPM is to test hydrologic and ecosystem-level responses to opening of large gaps in levees and filling of canals at a large but manageable experimental scale. The USGS role will be to conduct the experimental and modeling work to assess how increased sheetflow across various levels of levee removal and canal backfill designs perform in terms of transport of sediments and associated nutrients to downstream areas. A 3-year test period is planned which will not only reveal the first response characteristics of levee removal and increased sheetflow, but which will establish the sites and protocols for further evaluation in later years to assess the long term geomorphic and ecosystem-level changes that can be expected over a large proportion of the central Everglades after DECOMP is fully implemented. DPM's implementation schedule has been slowed for several reasons, including the need for an Environmental Impact Statement. FY07 will therefore largely be a year of planning and DPM activities will ramp up quickly in FY08. Meanwhile important additional scientific tasks remain for FY07 relating to DECOMP and DPM that can be best accomplished at reference site WCA-3A-5.

The results of our research in FY07 will therefore provide crucial information for accurate predictions of the microtopography and water quality effects of restoration projects such as the WCA-3A Decompartmentalization Project and TAMIAMI TRAIL bridge expansion. Results will also be highly relevant to answering key questions associated with changing landscape characteristics in the Everglades (e.g. Landscape-Scale Modeling Study, Ridge and Slough Performance Standards), as well as all projects concerned with changing water quality and the need for more modern water-quality performance standards in the Everglades (e.g. Comprehensive Integrated Water Quality Feasibility Study). Finally, the information gained on particle and solute transport will aid critical modeling efforts that support the Loxahatchee Internal Canal Structures Project.

Specific Task Product(s): [List and include expected delivery date(s).]

Harvey, J.W., and others. Simulation of transport of solute and fine suspended particulates in the ridge and slough landscape of the Everglades (to be submitted to a journal by June 2007).

Larsen, L.G., Harvey, J.W., and Crimaldi, J.P., submitted. A delicate balance: feedback between landscape morphology, water flow, vegetation dynamics, and sediment transport in a low-gradient, lotic peatland ecosystem. Ecological Monographs (submitted August 3, 2006).

McCormick, P., Harvey, J. and Orem, B. Detecting Pre-drainage baseline conditions of water flow, hydrologic connectivity, and water quality in the Everglades (initially to be delivered as a white paper to provide scientific input Loxahatchee Internal Canal Structures Project, then to be summarized in a journal paper)

Noe, G.B., Harvey, J.W., and Saiers, J.E. In press. Characterization of suspended particles in Everglades wetlands. Limnology & Oceanography. (publication expected early 2007).

Noe, G.B. and Childers, D.L. In press. Phosphorus budgets in Everglades wetland ecosystems: The effects of hydrology and nutrient enrichment. Wetlands Ecology and Management. (publication expected early 2007).

Noe, G.B., and others. Hydrologic and microtopographic controls on suspended particle characteristics and transport in a subtropical wetland (to be submitted to journal by March 2007).

Saiers, J.E., and others. Wetland processes affecting transport and interception of micron-sized suspended particulates in the ridge and slough landscape of the Everglades (to be submitted to journal by December 2006).

Expected Results and Significance:
DOI's Science Plan (2005) highlights the need to understand the influence of hydrology on nutrient and contaminant transport and cycling. The National Academy of Sciences has also emphasized the importance of sediment transport to understanding and restoring the Everglades. Our proposed experiments and modeling are fundamental to building a reliable predictive capability of how the Everglades will respond to the restoration's higher flows. Our proposed combination of empirical and modeling research will support several of the critical information needs identified by the National Academy of Science and DOI Everglades Science Plan. First, this work has direct bearing on projects such as the WCA-3A Decompartmentalization Project, and Tamiami Trail Bridge Expansion projects, but it is also highly relevant to all projects related to preservation of landscape structure (e.g. Landscape-Scale Modeling Study and Ridge and Slough Performance Standards), as well as all projects concerned with changing water quality and the need for more modern water-quality performance standards in the Everglades (e.g. Comprehensive Integrated Water Quality Feasibility Study). Our study will identify the critical hydrologic, chemical, and biologic linkages that have shaped both the pre-drainage Everglades and the current landscape. This information is necessary for understanding the critical factors that sustain the ridge and slough landscape and ecosystem function, and is also necessary for predicting some of the unintended side-effects of restoration activities that may accompany increases in flow and hydrologic connectivity (a focus identified as important by both DOI and the National Academy of Science). Finally, the information gained on particle and solute transport will aid critical modeling efforts that support the Loxahatchee Internal Canal Structures Project. In conclusion, our proposed work will support key science needs for no less than six of the projects identified by DOI as critical to the success of the Everglades restoration.

Status: Active

References Cited:

Crisfield, E., and McVoy, C. 2004. Role of flow-related processes in maintaining the ridge and slough landscape, Joint Conference on the Science and Restoration of the Greater Everglades and Florida Bay Ecosystem, Palm Harbor, FL.

Harvey, J.W., Newlin, J.T., Krest, J.M., Choi, J., Nemeth, E.A., and Krupa, S.L. 2005. Surface-Water and Ground-Water Interactions in Water Conservation Area 2A, Central Everglades, USGS SIR 2004-5069.

Harvey, J.W., Saiers, J.E., and Newlin, J.T. 2005. Solute transport and storage mechanisms in wetlands of the Everglades, south Florida. Water Resources Research, 41, W05009, doi:10.129/2004WR003507.

Harvey, J.W. and Sklar, F. 2006. WORKSHOP: Development of a Conceptual Model for Ridge and Slough Landscape Dynamics. Greater Everglades Ecosystem Restoration Conference (GEER), June 5-9, 2006, Lake Buena Vista, FL, p. 91.

National Research Council. 2003. Does water flow influence Everglades landscape patterns, Washington, D.C., The National Academies Press, 41 p. http://books.nap.edu/catalog/10758.html.

Noe, G.B., Scinto, L.J., Taylor, J., Childers, D.L., and Jones, R.D. 2003. Phosphorus cycling and partitioning in an oligotrophic Everglades wetland ecosystem: a radioisotope tracing study. Freshwater Biology 48(11):1993-2008.

Noe, G.B. and Childers, D.L. In press. Phosphorus budgets in Everglades wetland ecosystems: The effects of hydrology and nutrient enrichment. Wetlands Ecology and Management.

Noe, G.B., Harvey, J.W., and Saiers, J.E. In press. Characterization of suspended particles in Everglades wetlands. Limnology & Oceanography.

Saiers, J.E., Harvey, J.W., and Mylon, S.E. 2003. Surface-water transport of suspended matter through wetland vegetation of the Florida Everglades. Geophysical Research Letters 30(19), 1987, doi:10.1029/2003GL018132.

Science Coordination Team. 2003. The role of flow in the Everglades ridge and slough landscape, South Florida Ecosystem Restoration Working Group, 62 p. http://www.sfrestore.org/sct/docs/.

Schaffranek, R.W. 2004. Sheet-flow velocities and factors affecting sheet-flow behavior of importance to restoration of the Florida Everglades, U.S. Geological Survey Fact Sheet 2004-3123, 4 p. http://pubs.er.usgs.gov/pubs/fs/fs20043123

U.S. Department of the Interior, 2005. Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida. http://sofia.usgs.gov/publications/reports/doi-science-plan/2005-DOI-Science-Plan-final.pdf.



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