2005 Salt Lake City Annual Meeting (October 16–19, 2005)

Paper No. 19
Presentation Time: 1:30 PM-5:30 PM


VAN EATON, Alexa, ZIMMERMAN, Andrew, JAEGER, John M. and BRENNER, Mark, Geological Sciences, University of Florida, PO Box 112120, Gainesville, FL 32611, lexi303@ufl.edu

Naples Bay, extending 10 km along the southwest coast of Florida, has undergone significant urbanization over the past decade. Characteristic of many watersheds in Florida, the rather shallow (1-8 m) estuarine system experiences dredge & fill operations, channelization, and episodic urban runoff, which alter hydrological cycles and produce eutrophic effects. Previous evidence shows that decreased tidal flushing and increased water column stratification has occurred as a result of these changes, affording the ability to determine how such development is reflected in the geochemistry of a relatively sensitive ecosystem. Radioisotopic (Pb-210 and Cs-137), textural, and bulk elemental analyses are being performed on sediment cores from 5 representative regions of the bay. This information will be used to compare pre-urbanization with present sedimentological and ecological conditions. Current radiogenic isotope data reveal high levels of excess Pb-210 activity deeper than 18 cm below the surface, suggesting that recent accumulation rates faster than sea level rise are a possible effect of shoreline development. Ongoing analyses will help quantify anthropogenic impacts on accumulation rates, organic matter sources, and sedimentary structures in the Naples Bay estuary.