소양호에서 세균군집구조의 계절적.수직적 변화

Seasonal and Vertical Change of Bacterial Communities in Lake Soyang

소양호에서 fluorescent in situ hybridization 방법을 이용하여 세균군집의 계절과 수심에 따른 변화를 조사하였다. 이 방법에 사용된 oligonucleotide probe는 EUB338, ALF1b, BET42a, GAM42a 와 CF probe 였다. 조사기간중 Proteobacteria $\alpha$-group 은 0.7~32.9% 이었으며 $\beta$-group은 1.0~25.8%, $\gamma$-group은 2.4~37.1%, Cytophaga-Flavobacterium group은 4.7~23.6%의 분포를 나타내었다. 계절별로 살펴보면 규조류가 우점하는 봄펄에는 $\gamma$-group 이, 유기물의 농도가 낮고 수온이 높은 여름철에는 $\alpha$-group 이 우점하였으며, 남조류가 우점하는 가을철에 총세균수에 대한 Eubacterial group 의 비율이 크게 감소하여 특정 group의 우점현상은 나타나지 않았다. 이처럼 소양호는 계절과 수심에 따라 군집구조가 변화하였으며, 특히 세균의 군집구조는 식물플랑크톤의 천이와 밀접한 관계를 보이는 것으로 나타났다.

This sludy was conducted to investigate the change of bacterial co~munities with season and depth in Lake Soyang. Korea, using fluorescence in situ hybridization (FISH). The oligonucleotide probes used in this study were EUB338, ALF I b. GAM42a, and CF, The percentage of h e Proleobacteria a $\alpha$-group ranged from 0.70 to 33% the $\beta$-group from 1.0 to 26% they -group from 2.4 Lo 37% and Cytophagn and Flavobactefin groups from 4.7 to 24% duing the study period (April Lo November, 1998). They $\gamma$-group was dominant in spring when Asterionella was dominant. and a $\alpha$-group was dominant in summer when the organic content was low and Dinobryon was dominant. However, a specific group was not dominant in ？dl when cyanobacteria group was dominant and the ratio of eubacleria to total bacteria was very low. Therefore, the bacterial communities in Lake Soyang changed with season and depth, which seems to be associated with the telnporal succession of phytoplanlaons.