|Smith Jr, Sammie|
Submitted to: Management of Landscapes Disturbed by Channel Incision Stabilization Rehabi
Publication Type: Abstract Only
Publication Acceptance Date: 9/17/1996
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: One of the major objectives of the Mississippi Delta Management Systems Evaluation Area project (MDMSEA) is to demonstrate innovative/alternative farming systems composed of combinations of best management practices (BMPs) for the improvement of Delta water quality/ecology on a farm, watershed, and landscape scale. BMPs consist of no-till, grass filter strips/waterways, within-field sediment impoundments (created by slotted-board risers), and riparian zones and are intended to reduce pesticide-laden sediment transport in surface runoff to receiving waters, namely, oxbow lakes. However, associated with these BMPs are increased infiltration and the potential for pesticides in solution to leach beyond the root zone. This poster display describes the installation and distribution of shallow ground water sampling wells and the efforts being made to evaluate the effects of BMPs on pesticide percolation to shallow water tables that may be hydraulically connected to nearby oxbow lakes. Ground water samples are collected at depths of 5, 10, and 15 feet in critical flow areas, including riparian zones, within the MDMSEA watersheds and analyzed for pesticides. Pesticide metabolites are also determined in order to evaluate pesticide processing/transformation that is occurring within the BMPs. Deeper sediment cores from the oxbow lakes are collected and evaluated for evidence of subsurface pesticide transport. Preliminary results from well water analyses show only the occasional presence of sub-ppb levels of targeted current-use pesticides. Preliminary results from analyses of lake sediment cores show the consistent presence of sub-ppm levels of targeted persistent/past-use pesticides including DDT, DDD, and DDE.