Biogenic Carbonate Production in Florida Bay

This paper reviews previous work on biogenic carbonate production within Florida Bay and present new data on production from the Upper Cross Bank and Buchanan Key areas. Production figures for bank and lake environments are calculated from standing crop surveys and growth rates determined from published work and short-term growth measurements. The organisms studied are: Porites, Thalassia, epibionts, molluscs, Penicillus, soritid foraminifera and Halimeda listed in order of decreasing carbonate productivity. Production figures indicate that banks produce twice as much skeletal carbonate per unit area as lakes. However, lakes are much larger than banks and, within the study areas, lakes generate about four times the amount of sediment as that formed on banks. This excess sediment is considered to have been transported to the southwest of the bay to areas with larger constructional banks or out of the Florida Bay system. The migrating Upper Cross Bank generates sediment at rates nearly one order of magnitude less than those of the more stable Buchanan bank and the back-reef mound of Tavernier. Production rates may therefore be effecting bank stability.