Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/6/2002
Publication Date: 1/1/2003
Citation: Kim, J., Gan, J., Farmer, W.J., Yates, S.R., Papiernik, S.K., Dungan, R.S. 2003. Organic matter effects on phase partition of 1,3-dichloropropene in soil. Journal of Agricultural and Food Chemistry. 51:165-169.
Interpretive Summary: Several laboratory experiments were conducted to obtain information on the effect of organic material, such as manure, on the behavior of fumigants such as 1,3-dichloropropene in soils. The experiments investigated how the fumigant 1,3-dichloropropene partitions between water and air, and soil and water. This is important information because fumigant mobility in soil depends on how the chemical partitions between the soil, water and air phases. Increasing soil organic matter generally increases chemical adsorption to the soil particles which reduces fumigant mobility. This suggests that adding organic material to soils may help to reduce the potential for offsite movement.
Technical Abstract: The fumigant 1,3-dichloropropene (1,3-D) is an important replacement to methyl bromide (MeBr). This study was conducted to better understand phase partitioning of 1,3-D and the role of organic matter in its adsorption to soil. Partitioning of 1,3-D between air and water (KH) and soil and water (Kf) were determined by quantifying the concentration in both phases upon equilibrium. At 20 deg C, the KH of (Z)- and (E)-1,3-D was 0.052 and 0.033, respectively. In three California soils, the Kf of 1,3-D isomers ranged from 0.39 to 0.60, and the Koc ranged from 35 to 60. The relatively high KH and low Kf imply that 1,3-D is highly mobile in most soils after subsurface application. Adsorption of 1,3-D in native soils and soils amended with manure compost increased with increasing soil organic matter content. This suggests that organic wastes may be applied to soil to increase 1,3-D adsorption, thus reducing its potential for offsite movement.