Title Monitoring of Soil Bacterial Community and Some Inoculated Bacteria After Prescribed Fire in Microcosm
Author Hong-Gyu Song1, Ok-Sun Kim2, Jae-Jun Yoo2, Sun-Ok Jeon2, Sun-Hee Hong2, Dong-Hun Lee3, and Tae-Seok Ahn2,*
Address 1Division of Biological Sciences, Kangwon National University, Chuncheon 200-701, Republic of Korea, 2Department of Environmental Science, Kangwon National University, Chuncheon 200-701, Republic of Korea, 3Division of Life Sciences, Chungbuk National University, Cheongju 361-763, Republic of Korea
Bibliography Journal of Microbiology, 42(4),285-291, 2004,
Key Words Soil bacterial community, prescribed fire, fluorescent in situ hybridization (FISH), inoculation
Abstract The soil bacterial community and some inoculated bacteria were monitored to assess the microbial responses to prescribed fire in their microcosm. An acridine orange direct count of the bacteria in the unburned control soil were maintained at a relatively stable level (2.0~2.7 x10^9 cells/g^-1 . soil) during the 180 day study period. The number of bacteria in the surface soil was decreased by fire, but was restored after 3 months. Inoculation of some bacteria increased the number of inoculated bacteria several times and these elevated levels lasted several months. The ratios of eubacteria detected by a fluorescent in situ hybridization (FISH) method to direct bacterial count were in the range of 60~80% during the study period, with the exception of some lower values at the beginning, but there were no definite differences between the burned and unburned soils or the inoculated and uninoculated soils. In the unburned control soil, the ratios of [alpha]-, [beta]- and [gamma]-subgroups of the proteobacteria, Cytophaga-Flavobacterium and other eubacteria groups to that of the entire eubacteria were 13.7, 31.7, 17.1, 16.8 and 20.8%, respectively, at time 0. The overall change on the patterns of the ratios of the 5 subgroups of eubacteria in the uninoculated burned and inoculated soils were similar to those of the unburned control soil, with the exception of some minor variations during the initial period. The proportions of each group of eubacteria became similar in the different microcosms after 6 months, which may indicate the recovery of the original soil microbial community structure after fire or the inoculation of some bacteria. The populations of Azotobacter vinelandii, Bacillus megaterium and Pseudomonas fluorescens, which had been inoculated to enhance the microbial activities, and monitored by FISH method, showed similar changes in the microcosms, and maintained high levels for several months.
Download PDF p.285-291.pdf