| Title |
Analysis of Bacterial Community Structure at Upper, Mid, Lower Part of Nak-Dong River using FISH |
| Authors |
이영옥 ( Lee Yeong Og ) ; 박지은 ( Park Ji Eun ) ; 신승필 ( Sin Seung Pil ) ; 안영희 ( An Yeong Hui ) |
| Keywords |
FISH; fluorescence in situ hybridization; α;β;γ-subclasses proteobacteria; Cytophaga-Flavobacterium group; nitrifying bacteria; Nak Dong River |
| Abstract |
For conducting the comparative analysis of the eubacterial community structure including nitrifying bacteria at 8 sampling sites throughout the N마-Dong River, FISH(fluorescence in situ hybridization) method was employed. The total ratio of each determined eubacterial group such as α·β·γ-subclasses protebacteria and Cytophaga-Flavobacterium(CF) group to total counts stained by DAPI at each site varied 9.3∼42.5% with the highest value at uppermost part. And each ratio of determined eubacterial groups reached mostly under 10% except those of CF group(23%) at uppermost part. Futhermore, compared to lower part, upper part represented higher proportions of γ-subclass proteobacteria comprised in most of fast growing bacteria on degradable organics. Also the variations of ammonia-oxidizing bacteria ranged from 2.7×10⁴to 18.3×10⁴ cells/㎖ with the lowest value in lower part and the highest value in mid part whereas those of nitrite-oxidizing bacteria varied 5.2∼7.7×10⁴cell/㎖ without noticeable differences throughout the sites. Additionally, the ratio of nitrifying bacteria to total counts ranged from 1.3% to 13.6?%, regardless of those of ammonia/nitrite-oxidizing bacteria. Overall, it implies that the upper part of Nak-Dong River represented comparatively better degradabilities of organic materials than their Lower part except at one site in upper part passed An-Dong City. By the contrast, the other part of Nak-Dong River, especially after merging the Gum-Ho River revealed lower detectability of FISH resulted from their cellular activity. So it could be said that the lower part of Nak-Dong River might be a ecosystem of which physico-chemical environment may have inhibited the activities of bacteria functioned as decomposer of organic matter. |