Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2003
Publication Date: December 8, 2003
Citation: Bialek Kalinski, K.M., Wilcox, K., Angier, J., McCarty, G.W., Rice, C. 2003. Fate of herbicides in the riparian buffer zone of a small first-order agricultural watershed [abstract]. American Chemical Society Abstracts. p. 1.
The effectiveness of a riparian buffer in removing herbicides, atrazine and metolachlor, applied to an agricultural field was studied. The riparian system under study contains a first-order stream that receives ground water and surface runoff from the field. We monitored the fate of parent herbicides and their degradation products to determine the ability of the riparian buffer to remove these agrochemicals from the environment. Ground water that moves through the field/riparian buffer system exfiltrates at different rates in various zones of the buffer. For this study we selected sites within the buffer characterized by fast, moderate or slow upwelling of ground water and measured the concentration of herbicides and their degradation products in the surface and ground water at different depths within the soil profile. The majority of monitored compounds were removed in the riparian buffer more effectively following transport through the slow upwelling zone. The buffer was less effective in removing metolachlor degradation products, especially metolachlor-ethanosulfonic acid (metolachlor-ESA). An especially high discharge of metolachlor-ESA to the surface was observed in fast upwelling zones within the riparian buffer. These fast upwelling zones may limit the effectiveness of a riparian buffer in remediation of agricultural contamination.