title: Diazinon and permethrin mitigation across a grass-wetland buffer.
abstract: Vegetated buffers of different designs are often used as edge-of-field treatment practices to remove pesticides that may be entrained in agricultural runoff. However, buffer system efficacy in pesticide runoff mitigation varies widely due to a multitude of factors including, but not limited to, pesticide chemistry, vegetation composition, and hydrology. Two experimental systems, a control (no vegetation) and a grass-wetland buffer system, were evaluated for their ability to retain diazinon and permethrin associated with a simulated storm runoff. The two systems were equally inefficient at retaining diazinon (mean 9.6 % retention for control and buffer). Grass-wetland buffers retained 83 % and 85 % of cis- and trans-permethrin masses, respectively, while the control only retained 39 % and 44 % of cis- and trans-permethrin masses, respectively. Half-distances (the distance required to decrease pesticide concentration by one-half) for both permethrin isomers were 26 %-30 % shorter in grass buffers (22-23 m) than in the control (32 m). The current study demonstrates treatment efficacy was a function of pesticide properties with the more strongly sorbing permethrin retained to a greater degree. The study also demonstrates challenges in remediating multiple pesticides with a single management practice. By using suites of management practices, especially those employing vegetation, better mitigation of pesticide impacts may be accomplished.
authors.affiliation: Water Quality and Ecology Research Unit, USDA-ARS National Sedimentation Laboratory, PO Box 1157, Oxford, MS, 38655, USA, matt.moore@ars.usda.gov.
authors.forename: M T
authors.initials: MT
authors.lastname: Moore
authors.forename: R
authors.initials: R
authors.lastname: Kröger
authors.forename: M A
authors.initials: MA
authors.lastname: Locke
authors.forename: R E
authors.initials: RE
authors.lastname: Lizotte
authors.forename: S
authors.initials: S
authors.lastname: Testa
authors.forename: C M
authors.initials: CM
authors.lastname: Cooper
mesh_terms: D000383:Agriculture; D001673:Biodegradation, Environmental; D003976:Diazinon / Q000302:isolation & purification* / Q000378:metabolism*; D006207:Half-Life; D026023:Permethrin / Q000302:isolation & purification* / Q000378:metabolism*; D006109:Poaceae / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism; D053833:Wetlands
chemical_list: D014874:Water Pollutants, Chemical; D026023:Permethrin; D003976:Diazinon