Sediment Dynamics in a Florida Lake
Grant
Overview
abstract
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Bottom sediments directly influence water quality by releasing nutrients (produced when freshly deposited organic matter is remineralized, converted back to inorganic constituents) to the overlying water and consuming dissolved oxygen from the water column in the process. The study of distribution and fate of these diagenetic products in the water column is important because the deposition, diagenesis (chemical and physical changes of the sediment) and subsequent transport of diagenetic products into overlying waters is an additional process in the nutrient/contaminant pathway that is often overlooked. Resuspension of bottom sediments (effectively removing sediments from the bottom and adding to the suspended sediment load), by physical mixing of overlying waters, results in the dispersal of particle bound contaminants and the advective release of dissolved constituents from interstitial waters (water contained in pore spaces between the grains of sediments, also referred to as porewater) into overlying surface waters. This advective transport of porewater and diagenetic end-products (Nitrogen/Phosphorus/Carbon) into surface waters may serve to increase water column nutrient concentrations and potentially exacerbate the poor water quality. This study will evaluate sediment deposition, accumulation, and potential removal processes in a Florida lake. We will use natural radiochemical tracers (Pb-210, Be-7, Th-234) to evaluate these sediment processes.
date/time interval
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August 2010 - September 2011
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