Submitted to: American Water Resources Association Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2004
Publication Date: 10/31/2004
Citation: Moore, M.T., Cooper, C.M., Smith Jr, S., Cullum, R.F., Knight, S.S., Locke, M.A. 2004. Planting for success: Using aquatic vegetation to mitigate agricultural runoff. American Water Resources Association Conference Proceedings. CD-ROM. Interpretive Summary:
Technical Abstract: In intensively cultivated areas, agriculture is a significant source of pesticides associated with storm runoff. When these pollutants enter aquatic receiving waters such as rivers, streams, or lakes, they have the potential to damage nearby aquatic ecosystems. Constructed wetlands are one of many suggested best management practices designed to help alleviate this potential problem. A constructed wetland (190 m x 24 m) comprised of two cells was used to determine fate and transport of a simulated storm runoff event containing the insecticide diazinon and suspended sediment. Wetland water, sediment, and plant samples were collected spatially and temporally. Results indicated that 69% of the study's measured concentrations were associated with plant material, while 18% and 13% were measured in sediment and water, respectively. Mean diazinon concentrations in water, sediment, and plants for the 55-d study were 18.1 (4.5) ug/L, 26.0 (8.0) ug/kg, and 97.8 (10.7) ug/kg, respectively. Aqueous concentrations fluctuated in the wetlands between 51-86 ug/L fo the first four hours of the experiment; however, by 9 h, aqueous concentrations were approximately 16 ug/L. During the 55-d experiment, 0.3 m of rainfall contributed to fluctuations in diazinon concentrations. Plant pesticide concentrations indicated the importance of vegetation in sorption and mitigation. Results of this experiment can be used to model future design specifications for mitigation of diazinon and other pesticides.