Synthesis of Sediment Production, Transport, and Accumulation

Project Investigators: Robert B. Halley (retired), Dave Rudnick (point of contact) Project Start Date: 1995 End Date: 2000 Proposals Project Summaries Publications

Summary

This project will synthesize portions of six projects that deal in diverse but complimentary aspects of sediments in Florida Bay.

This project will synthesize portions of six projects that deal in diverse but complimentary aspects of sediments in Florida Bay. Results from those projects will be integrated with appropriate literature to develop a sediment budget for the lagoon/estuary system. The synthesis will be process oriented, describing the mechanisms by which sediments are formed, moved, and deposited to form mudbanks and islands. The summary will include recommendations to management questions such as the effects of sea-level rise on Florida Bay and expected impacts of increased fresh-water flows.

South Florida Ecosystem Restoration projects by Halley, Stumpf, Prager, Hansen, Holmes and Orem all deal with complementary aspects of sedimentation in the Bay. These can be interrelated by use of a sediment budget because 95-99% of the sediment in the Bay is produced by organisms that live in the environment. Individual project elements include the following processes: 1) modem rates of carbonate sediment production from radiocarbon measurements and geochemical measurements (Halley), mineralogical and chemical composition (Orem, Prager, Holmes) processes of erosion and deposition (Prager), resuspension and transport (Prager, Stumpf), recent deposition (Holmes) and the geography and geometry of net accumulation (Hansen, Halley). Carbonate productivity in the Bay can be calculated using three methods. Stockman et. al (1967) used accumulated sediments and dating to determine rates of sediment production.Stockman et. al (1967) and Boscence (1989, 1995) used a standing crop and turnover rate to determine short-term productivity. Large discrepancies exist between the long-term and short-term productivity measures. Halley, in a complementary project, is using geochemical methods to determine short-term productivity and carbonate precipitation. This geochemical validation and proposed sediment budget will indicate whether there has been a long-term change in the productivity of the Bay or if current processes can account for the differences in apparent sediment production and accumulation.

(Note: this is a new project starting in 1999.)

Proposals

• 1999

Project Summaries

• 2001

Publications

Abstracts

• Sediment Transport Processes and Sea-Floor Mapping in Florida Bay (from the Florida Bay Conference Proceedings, 1996)

Reports

• Florida Bay's Murky Past