title: Dissipation and runoff transport of metazachlor herbicide in rapeseed cultivated and uncultivated plots in field conditions.
abstract: The environmental fate of metazachlor herbicide was investigated under field conditions in rapeseed cultivated and uncultivated plots, over a period of 225 days. The cultivation was carried out in silty clay soil plots with two surface slopes, 1 and 5 %. The herbicide was detectable in soil up to 170 days after application (DAA), while the dissipation rate was best described by first-order kinetics and its half-life ranged between 10.92 and 12.68 days. The herbicide was detected in the soil layer of 10-20 cm from 5 to 48 DAA, and its vertical movement can be described by the continuous stirred tank reactor (CSTR) in series model. Relatively low amounts of metazachlor (less than 0.31 % of the initial applied active ingredient) were transferred by runoff water. More than 80 % of the total losses were transferred at the first runoff event (12 DAA), with herbicide concentrations in runoff water ranging between 70.14 and 79.67 μg L-1. Minor amounts of the herbicide (less than 0.07 % of the initial applied active ingredient) were transferred by the sediment, with a maximum concentration of 0.57 μg g-1(12 DAA), in plots with 5 % inclination. Finally, in rapeseed plants, metazachlor was detected only in the first sampling (28 DAA) at concentrations slightly higher than the limit of quantification; when in seeds, no residues of the herbicide were detected.
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100, Agrinio, Greece.|Faculty of Agricultural Technology, T.E.I. of Epirus, Arta, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Mantzos
authors.affiliation: Department of Business Administration of Food and Agricultural Products, University of Patras, 30100, Agrinio, Greece.|Department of Chemistry, University of Ioannina, 45110, Ioannina, Greece.
authors.forename: Dimitra
authors.initials: D
authors.lastname: Hela
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100, Agrinio, Greece.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Karakitsou
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100, Agrinio, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Antonopoulou
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100, Agrinio, Greece. iokonst@cc.uoi.gr.|Department of Chemistry, University of Ioannina, 45110, Ioannina, Greece. iokonst@cc.uoi.gr.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Konstantinou
mesh_terms: D000081:Acetamides / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D029741:Brassica rapa / Q000737:chemistry / Q000378:metabolism; D004784:Environmental Monitoring; D006540:Herbicides / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D000081:Acetamides; D006540:Herbicides; D014873:Water Pollutants; C521990:metazachlor
keywords: Kinetics; Metazachlor; Rapeseed; Runoff water; Sediment; Soil dissipation