Resource Management

Diversity Management | Watersheds | Environmental Contaminants | Harmful Algal Blooms

Mosquito Control | Pesticides | Metals, PAH and PCB's

esticides

Organochlorine pesticides were extensively used in agricultural fields after WWII, and it was not until 1987 that EPA legislation banned sales. DDT, Toxiphene, and Chlordane are a few examples of these compounds. Organochlorines are persistent in soil and sediments, but transfer to the water column both as entrained sediment and via adsorption to dissolved organic carbon (Syracuse Research Corporation 1994). At relatively low concentrations, invertebrate populations in both sediment and water are adversely affected. Bioaccumulation has a detrimental impact on vertebrates as well.

Agricultural fields no longer in production are repositories for these pesticides. As this real estate is converted to residential or is restored, contaminated soils are often flooded. Remobilization of sequestered pesticides is a potential ecological risk for the estuaries downstream, both in the immediate impact on benthic invertebrates, but also in bioaccumulation as wading birds feed in affected areas.

Identifying potential ecological risks as these watersheds are developed is an essential tool for resource management. Several agricultural fields in production prior to 1978 in the District VI, Belle Meade and Southern Golden Gates Estates watersheds are now owned by the State of Florida. These are potential areas of restoration with overland sheet flow as a primary goal.