|Smith Jr, Sammie|
Submitted to: International Hydro-Science & Engineering International Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/28/2004
Publication Date: 6/5/2004
Citation: Ward, A.D., Moore, M.T., Bouchard, V.L., Powell, K., Mecklenburg, D., Cooper, C.M., Smith Jr, S. 2004. Water quality benefits for grassed fluvial features in drainage ditches. In: Proceedings of the 4th International Hydroscience Engineering Conference. May 30-June 3, 2004, Brisbane, Australia. p. 63-65. Interpretive Summary: Pesticides, excess nutrients, and sediment from agricultural runoff can pollute rivers, lakes, and streams. This research involves studying how drainage ditches that surround agricultural fields, can decrease the amount of pollutants being washed into surrounding water bodies. Study results indicated that pesticides in runoff bind to plant material in drainage ditches, and the plants also help with decreasing the amount of excess nutrients traveling from farm fields. This research will help farmers and natural resource managers design farm-specific management practices intended to improve water quality.
Technical Abstract: Concerns over agricultural contributions to water quality degradation have placed increased emphasis on discovering innovative best management practices to decrease the effects of runoff containing agricultural chemicals. Ongoing studies suggest that vegetated or partially vegetated ditches, together with a grass buffer strip and conservation practices, might be most effective in reducing downstream discharges of sediment, pesticides, and nutrients. This paper provides details on research being conducted by research teams located in the Midwest and Southern regions of the United States. Qualitative evidence and theory suggest ditches prone to filling with accumulated sediment may require less frequent cleanout if fluvial bars and benches are retained and/or they are constructed in a two-stage form. Studies conducted by the USDA-ARS National Sedimentation Laboratory have shown that vegetated agricultural drainage ditches play an important role in the mitigation of both nutrients and pesticides following runoff events. Results from these studies showed that within 3 hours, the majority of pesticides were associated with ditch vegetation. The Ohio authors are investigating the potential for nitrogen removal in agricultural ditches. Preliminary data suggest that differences in denitrification in one-stage and two-stage ditches favor this accumulation of organic carbon.