Estuaries function as efficient biogeochemical reactors. A broad spectrum of geochemical reactions and processes are initiated in response to the fundamental exchanges in water chemistry as rivers and groundwater mix into the seawater.
Within this study, geochemical reactivity of uranium (U238), dissolved organic carbon (DOC), iron (Fe), manganese (Mn), barium (Ba), and vanadium (V) were measured throughout the Tampa Bay Study area to find answers as to why this fresh/salt water mixing zone has a 2-3 times greater U concentration than those reported for other estuarine systems.
Elevated U behavior may be attributed to 1) physical mixing processes within the river; 2) U carrier phase reactivity; and/or 3) fluid exchange processes across sediment/water interface.
Investigation into the water column, pore waters, and riverine mixing within Tampa Bay, Florida, demonstrated that the estuarine distribution of U indicates a strong natural, geologic control which may also be influenced by enhanced fluid transport processes across the sediment/water interface.
The study of uranium geochemistry within estuaries provided us with an enhanced understanding of coastal systems and to what extent these complex surface/groundwater interactions influence the precious balance needed for sustainability within such a diverse environment.