Submitted to: Proceedings of International Research Conference on Methyl Bromide Alternatives
Publication Type: Proceedings
Publication Acceptance Date: September 11, 2006
Publication Date: November 6, 2006
Citation: Gao, S., Trout, T.J. 2006. Evaluation of water seals on emission reductions of 1,3-dichloropropene and chloropicrin. Proceedings of International Research Conference on Methyl Bromide Alternatives and Emission Reductions. Orlando, FL, Nov 6-9, 2006. Available: www.mbao.org/2006/06Proceedings/mbrpro06.html, pgs 9-1 - 9-3. Technical Abstract: Reducing emissions can minimize the detrimental impact of soil fumigation while maintaining the benefits of fumigants to agricultural productions. As a costly effective and environmentally friendly method, water seal (applying water to soil surface) has the potential to reduce emissions. This study determined the effectiveness of water seals to reduce emissions of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) by comparing with other surface seal methods in a field trial. Telone C35 (61% 1,3-D and 35% CP) was shank-applied to a sandy loam soil in San Joaquin Valley, CA. Surface treatments included standard high density polyethylene (HDPE) tarp over dry and pre-irrigated soil, virtually impermeable film (VIF) tarp, initial water seal immediately following fumigation, and intermittent water seals after fumigation. Among the surface seals, VIF and HDPE tarp over dry soil resulted in the lowest and the highest total emission losses, respectively. Intermittent water seals reduced 1,3-D and CP emissions significantly more than HDPE tarp alone and the initial water seal only following fumigation. The initial water seal reduced emission peak and delayed emission time. This provides a benefit for reducing the risks to workers and bystanders during fumigation. Pre-irrigated soil + HDPE tarp reduced fumigant emissions similarly as the intermittent water seals and also yielded the highest surface soil temperature which may benefit overall soil pest control.