Alternatives to MEBR for California Cropping Systems
Location: Water Management Research
Title: Effects of Water Seal on Reducing 1,3-Dichloropropene Emissions from Different Textured Soils
Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 18, 2008
Publication Date: January 5, 2009
Citation: McDonald, J.A. S. Gao, R. Qin, B.D. Hanson, T.J. Trout, and D. Wang. 2009. Effect of water seal on reducing 1,3-dichloropropene emissions from different soil textures. Journal of Environmental Quality. 38: 712-718.
Interpretive Summary: Research has shown that water seals (irrigation with sprinklers following fumigation) are effective to reduce emissions from soil fumigation in sandy loam soils. The potential of water seals to reduce emissions from other types of soils is not known. This study determined the effectiveness of water seals on emission reductions of Telone (1,3-D) by conducting soil column tests using three different textured soils (loamy sand, sandy loam, and clay loam). Results indicate that using same amount of water (initial 9 mm water just before fumigant injection followed by applications of 3 mm at 12 h and 24 h) reduced peak emissions and total emission loss effectively in all three soils. The amount of water used in this study did not reduce fumigant concentrations in soil-gas phase in all soils. This study indicates that water seal technique may be able to effectively reduce emissions across soil textures when proper amount of water is used. The impact on fumigant movement in soil as soil water content increase should be determined under field conditions.
Soil physical conditions can affect diffusion, environmental fate, and pest-control efficacy of fumigants in soil disinfestation treatments. Water seal (applying water using sprinklers to soil following fumigation) has shown effectiveness to reduce fumigant emissions from sandy loam soils. Soil column studies were conducted to compare the effectiveness of water seals for reducing 1,3-dichloropropene (1,3-D) emissions from three different textured soils (loamy sand, sandy loam, and clay loam). Treatments included an untreated control, an initial water seal (9 mm water applied immediately before fumigant injection), and intermittent water seals (initial 9 mm water seal followed by 3 mm at 12 and 24 h). The initial water seal was not exercised with the loamy sand; instead, reduced-amount intermittent water seals (initial 3 mm water followed by 1 mm at 12 and 24 h after fumigant application) were tested. Overall emission losses of 1,3-D from the control treatment were over a 2 wk monitoring period was 56% for loamy sand, 51% for sandy loam, and 43% for clay loam. The initial water seal reduced total 1,3-D emissions to 46% in the sandy loam and 31% in the clay loam. The intermittent water seals reduced emission loss to 26% for the loamy sand, 41% for sandy loam, and 21% for clay loam. The reduced-amount intermittent seals with the loamy sand had little effect. None of the water applications reduced fumigant concentrations in soil gas-phase. Results indicate that water sealing is an effective technique for reducing fumigant emissions from treated soils across wide texture classes without compromising the sterilization effect.