|Qin, Ruijun - UC DAVIS|
Submitted to: Journal of Environmental Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 26, 2007
Publication Date: January 14, 2008
Citation: McDonald, J.A., S. Gao, R. Qin, T. J. Trout, and B.D. Hanson. The effect of chemical and manure amendment with water application and tarp on 1,3-dichloropropene emissions from soil. Environ. Sci. Technol. 42, 398–402. Interpretive Summary: Various studies have tested the effectiveness of different surface seal (water, tarp) and soil amendments (chemicals, organics) on emission reductions but few tested the effectiveness of these methods used alone or in combinations on emission reductions of fumigants. To develop practical methods that can be applied in the field, we determined the effectiveness of ammonium thiosulfate and composted steer manure amendments to surface soil in combination with water application or high density polyethylene (HDPE) tarp on reducing emissions of 1,3-D from soil columns. Results showed that both the chemical and manure amendment with small amounts of applied water can effectively reduce 1,3-D emissions and are unlikely to affect fumigation efficacy in soil. More emission reductions can be achieved with additional HDPE tarp over the amendments. Although more costly, soil amendment with tarp may achieve ultra-low emissions and can be critical in maintaining the practical use of fumigants for many crops as more stringent regulations will be developed to control volatile organic compounds (VOC) emissions from pesticide use. Soil amendments with organic materials may have a great potential for adoption by growers due to practical considerations such as economics, easy application, and fewer negative environmental impacts.
Technical Abstract: Reducing fumigant emissions is required for minimizing bystander risk and environmental impact. Effective and economic field management methods including commonly used surface sealing technique and soil amendments are needed for achieving emission reductions. This research determined the effectiveness of ammonium thiosulfate (ATS) and composted manure amendments to surface soil in combination with water application or high density polyethylene (HDPE) tarp on reducing emissions of 1,3-D from soil columns. Surface treatments included an untreated control, water seal (single water application immediately following fumigant injection), ATS amendments at 1:1 and 2:1 molar ratio of ATS:fumigant, composted steer manure at 3.5 kg m-2, and HDPE tarp over 1:1 ATS or the manure amendment. Cumulative 1,3-D emission loss over two weeks was greatest for the control (52% of applied). The HDPE tarp over ATS and manure treatments had the lowest 1,3-D emissions at 24 and 16%, respectively. Treatments with ATS or manure alone reduced 1,3-D emissions (29'39%) more effectively than water seal (43%) and further benefit was gained with the addition of HDPE tarp. Amendment of surface soil with organic materials shows greater potential in minimizing fumigant emissions than with chemicals with the need for a better understanding of organic-fumigant reaction mechanism.