Greenhouse gas production and emission from a forest nursery soil following fumigation with chloropicrin and methyl isothiocyanate [An article from: Soil Biology and Biochemistry]

This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Soil fumigation is commonly used to control soil-borne pathogens and weeds. Our aim was to examine the effects of soil fumigation with chloropicrin (CP) and methyl isothiocyanate (MITC) on CH"4, N"2O and CO"2 production and emission. These effects on a SE USA forest nursery soil were examined in field and laboratory experiments. Following field fumigation, CH"4 surface emissions and concentrations in the soil atmosphere were unaffected. Both fumigants increased N"2O emissions rates significantly compared to non-fumigated controls, and the effects were still evident after 48 d. These findings are in contrast to fertilizer-induced N"2O emissions, which generally return to background within 2 wk after application. Depths of N"2O production were different for the two fumigants as determined by soil gas sampling, suggesting fumigant-specific stimulation mechanisms. CO"2 emissions (0-15 d) were not altered significantly, although sub-surface CO"2 concentrations did increase following fumigation with CP or MITC and remained elevated for CP treatment on d 48. CP-induced N"2O production was also stimulated in aerobic laboratory incubation studies, with surface soils exhibiting 10 to 100-fold greater production rates. MITC and a combination of CP/MITC also stimulated N"2O production, but the effect was significantly less than for CP alone. MITC suppressed and CP did not effect CO"2 production in the laboratory incubation. By comparing sterilized to non-sterile soils, >95% of these effects appear to be of biotic origin.