on day 1, 2, 3, 4, 5, 7, 9, 13, 17,20, 23, 28, 33, 40, 50, and 60 of the incubation period. Every time,approximately 35.0 ml were extracted and injected into 7.5 ml over-head bottle to be measured. In addition, samples of 20 g (wet weight)soil were collected from the plastic bottles at 3, 17, and 60 days to measure pH, Fe2+,NH4+ -N, and NO3 —N content, as well as the mi-crobial biomass carbon (MBC) and microbial biomass nitrogen (MBN).