Author
Lizotte, Richard | |
Knight, Scott | |
Locke, Martin |
Submitted to: Soil and Water Conservation Society Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 5/22/2009 Publication Date: 7/15/2009 Citation: Lizotte Jr, R.E., Knight, S.S., Locke, M.A. 2009. Temporal Changes in Pesticide Contamination of Beasley Lake: A Conservation Effects Assessment Program Watershed. Soil and Water Conservation Society 64th International Annual Conference Abstract Book, pp. 83. Interpretive Summary: Technical Abstract: Originally established for the Mississippi Delta Management Systems Evaluation Area project (1995-2001), Beasley Lake was designated in 2003 as the Mississippi Delta region national Conservation Effects Assessment Project watershed. Since monitoring began in 1995, the 915 ha watershed has been predominantly in row-crop production with the implementation of physical and cultural Best Management Practices (BMPs) to reduce soil loss and improve lake water quality. In 2003, 114 ha were enrolled in the Conservation Reserve Program (CRP). This study assessed the influence of BMPs combined with CRP on pesticide contamination in Beasley Lake from 2000-2008. A suite of 17 current-use and legacy pesticides and metabolites were measured in water and sediment. Peak lake water concentrations of current-use herbicides, current-use insecticides, and legacy compounds occurred during 2000, 2002, and 2002, respectively. Lowest lake water concentrations of current-use herbicides, current-use insecticides, and legacy compounds occurred during 2005. Overall, lake water pesticide contamination decreased annually until 2005-2006 and increased again in 2007-2008 due, in part, to a shift in row crop from no-till soybeans to conventional-till corn in 2007. Peak lake sediment concentrations of current-use herbicides, current-use insecticides, and legacy compounds occurred during 2008, 2000, and 2000, respectively. Lowest lake sediment concentrations of current-use herbicides, current-use insecticides, and legacy compounds occurred during 2004. Lake pesticide contamination progressively declined with the implementation of BMPs and CRP and increased again with changes in BMPs. |