title: Coupling of soil solarization and reduced rate fumigation: effects on methyl iodide emissions from raised beds under field conditions.
abstract: Using field plots, we studied the effect on methyl iodide (MeI) emissions of coupling soil solarization (passive and active) and reduced rate fumigation (70% of a standard fumigation) in raised beds under virtually impermeable film (VIF). The results showed that for the standard fumigation and the passive solarization + fumigation treatments, emissions from the nontarped furrow were very high (∼50%). Emissions from the bed top and sidewall of these treatments were relatively low but were increased in the latter due to the longer environmental exposure of the VIF covering with the coupled approach (increased tarp permeability). Overall, this approach offered no advantage over fumigation-only in terms of emission reduction. With active solarization + fumigation, the large application of hot water during solarization apparently led to severely limited diffusion causing very low total emissions (<1%). Although this suggests a benefit in terms of air quality, a lack of diffusion could limit the pesticidal efficacy of the treatment.
authors.affiliation: USDA-ARS, United States Salinity Laboratory, 450 West Big Springs Road, Riverside, California 92507, United States.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Ashworth
authors.forename: Scott R
authors.initials: SR
authors.lastname: Yates
authors.forename: Lifang
authors.initials: L
authors.lastname: Luo
authors.forename: Sang R
authors.initials: SR
authors.lastname: Lee
authors.forename: Richeng
authors.initials: R
authors.lastname: Xuan
mesh_terms: D000383:Agriculture; D005651:Fumigation; D006847:Hydrocarbons, Iodinated / Q000737:chemistry*; D007700:Kinetics; D010575:Pesticides / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014835:Volatilization
chemical_list: D006847:Hydrocarbons, Iodinated; D010575:Pesticides; D012987:Soil; D012989:Soil Pollutants; C014055:methyl iodide