Lake Okeechobee phosphorus

Reddy, K. R. and M. M. Eisher. 1991. Sediment resuspension effects on phosphorus flux across the sediment-water interface laboratory microcosm studies. In Lake Okeechobee Phosphorus Dynamics Study Biogeochemical Processes in the Sediments. Volume V. Einal Report submitted to South Florida Water Management District (Contract No. 531-M88-0445-A4), West Palm Beach, FL. 

Reddy KR, Flaig E, Scinto LJ, Diaz O, Debusk TA (1996) Phosphorus assimilation in a stream system of the Lake Okeechobee. J Am Water Resour Assoc 32 901-915... 

Examples of anthropogenic phosphate minerals are shown in Figure 9.14 (Harris, 2002 University of Florida). Figure 9.14a shows patina of black, poorly crystalline apatite on the surface of an oyster shell located near the bottom of an early American mound, which once served as a refuse pile (about 5,000 YBP). Bones of fish and other animals were discarded in the pile and became the source of phosphorus that precipitated on the nnderlying shell. Note that oyster shells are composed of calcium carbonate, npon which phosphate readily adsorbs and precipitates (scale bar = 5 mm). Figure 9.14b shows vivianite as precipitate on an aggregate from stream sediment near Lake Okeechobee, Florida, collected a short distance downstream from where a dairy barn floor routinely flushed manure. Soils and stream sediments in the area are naturally low in phosphorus (scale bar = 1 mm). 

In Lake Okeechobee, Elorida, Reddy and Eisher (1991) estimated that under normal wind events, the resuspension flux of soluble phosphorus can account for approximately 6-18 times the diffusive flux. In comparison, resuspension of loosely bound, organically rich sediments into the water column was found not to be a major factor for delaying the recovery of shallow Danish lakes (Jeppesen et al., 2003). However, the resuspension of nutrient-enriched benthic sediments (accumulated during eutrophication process) along with the diffusive flux can result in the release of nutrients supporting phytoplankton productivity and delay the overall recovery process. 

Moore, P. A. and K. R. Reddy. 1994. Role of and pH on phosphorus geochemistry in sediments of Lake Okeechobee, Florida. J. Environ. Qual. 23 955-964. 

Reddy, K. R., O. A. Diaz, L. J. Scinto, and M. Agami. 1995. Phosphorus dynamics in selected wetlands and streams of the Lake Okeechobee Basin. Ecol. Eng. 5 183-208. 

Brezonik, P. L. D. R. Engstrom, 1998. Modern and historic accumulation rates of phosphorus in Lake Okeechobee, Florida. J. Paleolim. 20 31-46. 

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