ACCELERATION OF 1,3-DICHLOROPROPENE DEGRADATION BY ORGANIC AMENDMENTSAND POTENTIAL APPLICATION FOR EMISSIONS REDUCTION

Emissions of the fumigant 1,3-dichloropropene (1,3-D) can result in de gradation of air quality in certain areas. The high emission potential of 1,3-D is caused by its rapid diffusion and comparatively slow degr adation in soil. One approach to reduce the emission is to enhance the surface soil's capacity to degrade 1,3-D. We investigated the capabil ity of two organic amendments, a composted manure (CM) and a biosolid- manure mix (BMI), to accelerate 1,3-D degradation in soil. Degradation of 1,3-D was significantly enhanced in amended soils compared to the unamended soil, and the degree of acceleration varied with the type as well as the rate of amendment. Compost manure was more effective in s timulating 1,3-D degradation than the less decomposed BM; even at an a mendment/soil ratio as low as 1:40 (w/w), degradation in the CM-amende d soil was two times faster than that in the unamended soil. The accel eration in CM-amended soils was a combined result of enhanced chemical and microbial degradation, since sterilization only partially reduced the enhanced degradation. The reduction of 1,3-D emissions by surface application of organic amendments was illustrated in a column experim ent: 1,3-D emission loss after injection at 30 cm was 30% from an unam ended Arlington sandy loam (a coarse-loamy, mixed, thermic Haplic Duri xeralf), but decreased to only 16% in the column containing 5% CM in i ts top 5-cm layer.