title: Washoff of Residual Photosystem II Herbicides from Sugar Cane Trash under a Rainfall Simulator.
abstract: Herbicides are often applied to crop residues, but their fate has not been well studied. We measured herbicide washoff from sugar cane trash during simulated rainfall, at 1, 8, and 40 days after spraying (DAS), to provide insight into herbicide fate and for use in modeling. Herbicides included are commonly used in the sugar industry, either in Australia or in Brazil. Concentrations of all herbicides and applied Br tracer in washoff declined exponentially over time. The rate of washoff during rainfall declined with increasing DAS. Cumulative washoff as a function of rainfall was similar for most herbicides, although the most soluble herbicides did have more rapid washoff. Some but not all herbicides became more resistant to washoff with increasing DAS. Of the total mass washed off, 80% washed off in the first 30 mm (∼40 min) of rainfall for most herbicides. Little herbicide remained on the trash after rainfall, implying nearly complete washoff.
authors.affiliation: Department of Natural Resources and Mines , 203 Tor Street, Toowoomba, Queensland 4350, Australia.
authors.forename: Aaditi
authors.initials: A
authors.lastname: Dang
authors.affiliation: Department of Natural Resources and Mines , 203 Tor Street, Toowoomba, Queensland 4350, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Silburn
authors.forename: Ian
authors.initials: I
authors.lastname: Craig
authors.affiliation: Department of Natural Resources and Mines, EcoSciences Precinct , Boggo Road, Dutton Park, Queensland 4102, Australia.
authors.forename: Melanie
authors.initials: M
authors.lastname: Shaw
authors.affiliation: Department of Natural Resources and Mines , 203 Tor Street, Toowoomba, Queensland 4350, Australia.
authors.forename: Jenny
authors.initials: J
authors.lastname: Foley
mesh_terms: D000383:Agriculture; D001315:Australia; D001938:Brazil; D006540:Herbicides / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry; D011891:Rain / Q000737:chemistry; D031786:Saccharum / Q000737:chemistry*; D014866:Waste Products / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D006540:Herbicides; D014866:Waste Products; D014874:Water Pollutants, Chemical
keywords: Great Barrier Reef; ametryn; atrazine; bromide; diuron; hexazinone; metolachlor; tebuthiuron; water quality