Submitted to: Pesticide Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 13, 2001
Publication Date: October 1, 2001
Citation: DUNGAN, R.S., GAN, J., YATES, S.R. EFFECT OF TEMPERATURE, ORGANIC AMENDMENT RATE AND MOISTURE CONTENT ON THE DEGRATATION OF 1,3-DICHLOROPROPENE IN SOIL. PESTICIDE MANAGEMENT SCIENCE. 2001. Interpretive Summary: 1,3-Dichloropropene (1,3-D) is considered a viable alternative to MeBr, however, atmospheric emission of 1,3-D is often associated with the deterioration of air quality. To minimize environmental impacts of 1,3-D, emission control strategies are in need of investigation. One approach to reduce 1,3-D emissions is to accelerate its degradation by incorporating organic amendments into the soil surface. In this study, we investigate the effect of various organic amendments on degradation of 1,3-D in soil. The degradation half-life was reduced by adding organic material to soil. The effect of temperature and amendment rate upon degradation should be considered when describing the fate and transport of 1,3-D isomers in soil. Use of organic soil amendments appears to be a promising method to enhance fumigant degradation and reduce volatile emissions.
Technical Abstract: In this study, we investigated the ability of four organic amendments to enhance the rate of degradation of two 1,3-D isomers, (Z)- and (E)-1,3-D in a sandy loam soil. Degradation of (Z)- and (E)-1,3-D was well described by first-order kinetics and rates of degradation were similar between the two isomers. Of the organic amendments tested, composted steer manure (SM) was the most reactive. The half-life of the (Z)- and (E)-isomer in unamended soil at 20oC was 6.3 d; those of 5% SM-amended soil were 1.8 and 1.9 d, respectively. At 40oC, the half-life of both isomers in 5% SM-amended soil was 0.5 d. Activation energy values for amended soil at 2, 5 and 10% SM were 56.5, 53.4 and 64.5 kJ mol-1, respectively. At 20oC, the contribution of degradation from biological mechanisms was largest in soil amended with SM, but chemical mechanisms accounted for greater than 58% of the (Z)- and (E)-1,3-D degradation.