title: Effectiveness of Integrated Best Management Practices on Mitigation of Atrazine and Metolachlor in an Agricultural Lake Watershed.
abstract: The study examined the influence of land-use (cropping patterns) and integrated agricultural best management practices (BMPs) on spring herbicide levels in an agricultural watershed. Atrazine and metolachlor were applied for weed control during spring of 1998-2002, 2005, and 2007-2013. Watershed-wide mass of applied herbicides ranged from 12.7 to 209.2 g atrazine and 10.9-302.2 g metolachlor with greatest application during 1998, 2009-2010 (atrazine) and 2007-2013 (metolachlor). Spring herbicide concentrations in Beasley Lake water ranged from below detection to 3.54 μg atrazine/L and 3.01 μg metolachlor/L. Multiple linear regression analyses with cropping patterns, BMPs, rainfall and time as independent variables, showed atrazine applications were associated with increases in cotton acreage and quail buffer, while metolachlor applications increased over time. Multiple linear regressions showed lake atrazine concentrations were associated with conservation tillage, rainfall, and corn, while lake metolachlor concentrations were associated with the cumulative metolachlor application and sediment retention pond installation.
authors.affiliation: USDA-ARS, National Sedimentation Laboratory, Oxford, MS, 38655, USA. richard.lizotte@ars.usda.gov.
authors.forename: Richard
authors.initials: R
authors.lastname: Lizotte
authors.affiliation: USDA-ARS, National Sedimentation Laboratory, Oxford, MS, 38655, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Locke
authors.affiliation: USDA-ARS, National Sedimentation Laboratory, Oxford, MS, 38655, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Bingner
authors.affiliation: USDA-ARS, National Sedimentation Laboratory, Oxford, MS, 38655, USA.
authors.forename: R Wade
authors.initials: RW
authors.lastname: Steinriede
authors.affiliation: USDA-ARS, National Sedimentation Laboratory, Oxford, MS, 38655, USA.
authors.forename: Sammie
authors.initials: S
authors.lastname: Smith
mesh_terms: D000081:Acetamides / Q000032:analysis*; D000383:Agriculture; D001280:Atrazine / Q000032:analysis*; D006540:Herbicides / Q000032:analysis; D060106:Lakes / Q000737:chemistry*; D017410:Practice Guidelines as Topic; D012621:Seasons
chemical_list: D000081:Acetamides; D006540:Herbicides; D001280:Atrazine; C051786:metolachlor
keywords: Buffers; CEAP; Conservation tillage; Cropping patterns; Herbicides