Effect of Sheet Flow on Transport of Suspended Particles and Particle-Associated Nutrients in the Everglades Ridge and Slough Landscape: Phase II

Project Investigators: Judson Harvey, Gregory Noe, Raymond W. Schaffranek Project Personnel: Laurel Larsen, Daniel J. Nowacki, Jeff Woods, Leanna Westfall, Lauren McPhillips Project Start Date: 2008 End Date: 2010 Recent Funding: (FY08) USGS GE PES Work Plans

Summary

This project's overall objective is to conduct the needed field experiments to quantify the relative importance of hydrological, biogeochemical, and ecological processes to help determine the most effective means of preserving and restoring topographic heterogeneity and biotic diversity of the Everglades Ridge and Slough Landscape.

For more information, please see the Effect of Sheet Flow on Transport of Suspended Particles, and Particle-Associated Nutrients in the Everglades Ridge and Slough Landscape Project Webpage and the Everglades Sheet Flow and Sediment Transport Processes Team Webpage.

This project's overall objective is to conduct the needed field experiments to quantify the relative importance of hydrological, biogeochemical, and ecological processes to help determine the most effective means of preserving and restoring topographic heterogeneity and biotic diversity of the Everglades Ridge and Slough Landscape.

A growing concern is that augmenting Everglades 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. Therefore, an important specific objective is to determine how far downstream suspended sediments and associated nutrients will be transported as a result of reconnected hydrology and higher sheetflow velocities.

Additional scientific questions that must be answered to support DECOMP include:

• How do the characteristic ridge and slough topographic variation and its associated vegetation patterns influence the sources, transport rates, rates of interception, and storage residence times 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 increased sheet flow velocities or the extent of canal backfilling after levee removal be the more important driver of changes in transport?
• What flow velocities are necessary to entrain and redistribute sediment in the ridge and slough landscape?

It will be necessary to answer all of the above questions to determine the most critical hydrological and biological factors that sustain the topographic heterogeneity of ridge and sloughs, and to effectively plan and manage the changes brought about by DECOMP. The results from these scientific investigations are also needed in order to anticipate possible unintended side-effects of restoration activities that may accompany the positive effects of restoration.

Work Plans

• 2008