|Zheng, W. - UC RIVERSIDE, CA|
|Guo, M. - UC RIVERSIDE, CA|
Submitted to: Pan-Pacific Conference on Pesticide Science
Publication Type: Abstract Only
Publication Acceptance Date: June 4, 2003
Publication Date: June 4, 2003
Citation: Papiernik, S.K., Dungan, R.S., Zheng, W., Guo, M., Yates, S.R. 2003. Emissions and distribution of fumigants following subsurface drip application. Pan-Pacific Conference on Pesticide Science. Honolulu, HI. Jun. 1-4, 2003. Technical Abstract: Soil fumigants are used to control a broad range of pests in high-cash-value crops. Their high volatility requires that management practices increase containment to reduce atmospheric emissions, increase efficacy, and prevent off-site transport. Experiments were conducted to monitor the volatilization and distribution of the fumigant compounds 1,3-dichloropropene, methyl isothiocyanate, and chloropicrin following subsurface drip application. Preliminary experiments conducted in sand mesocosms indicated that the configuration of the drip system (emitter spacing and single vs double drip lines) had little impact on emissions of any compound. Field experiments indicated that increasing the depth of application decreased maximum and cumulative flux. Tarping the bed with virtually impermeable plastic reduced cumulative emissions by >80 percent relative to standard 1-mil HDPE, and increased the proportion of the total flux occurring from the untarped furrows. These results indicate that use of low-permeability tarps can drastically reduce emissions, but to minimize volatilization losses, the entire soil surface must be covered.