Abstract
Denitrification rates were measured by acetylene blockage technique in slurried material collected from subsurface soil under paddy fields in Okabe, Saitama, under anaerobic, nitrate-amended conditions in the laboratory. The subsurface soil from 40-150cm showed the rates of 0.4-46ng N·g-1 wet soil·h-1, which were 1-2 orders magnitude smaller than those of the surface soils. The results demonstrate that denitrification can occur in subsurface soil under paddy fields in anaerobic conditions and can serve as a mechanism for nitrate removal from groundwater there.
