소양호에서 총세균수의 분포

최승익,변명섭,안태석 ( Seung Ik Choi,Myeong Seop Byeon,Tae Seok Ahn ) 한국하천호수학회 1997 생태와 환경 Vol.30 No.4

The total bacterial numbers were estimated by acridine orange direct count method in Lake Soyang monthly from January, 1990 to December. 1992. The range of total bacterial number was from 0.4×10^6 to 4.7×10^6 cells ·ml^-1. In epilimnion, the variation range was wider than other depths, while in hypolimnion was narrower. At August, when water temperature was highest, the bacterial numbers was also highest. This means that water temperature was one of the factor governing the bacterial abundance. In metalimnion, the bacterial number was higher than other depths during stratification. And spacially, the bacterial numbers near aquaculture net-cages were higher than those of dam site. This means that allochthonous materials such as terrestorial originated particles, organics and microbes from watershed and fish feed stimulated the bacterial growth.

백련어 포식 작용이 체외 효소 활성도에 미치는 영향

최승익,안태석,양상용,유홍일,유재근 ( Seung Ik Choi,Tae Seok Ahn,Sang Yong Yang,Hong Il Rhu,Jae Keun Ryu ) 한국하천호수학회 1994 생태와 환경 Vol.27 No.2

To define the effects of fish(Hypophihalmichthys molltrix) predation on phytoplankton densities and activities of extracellular enzymes including phosphatase, cellobiohydrolase and β-glucosidase were weekly investigated both in fish and control aquariums. Eventhough there was no increment of nutrients by fish predation, chl. a concentration in the fish aquarium was 12.6mg m^-3, twice higher than in the control, and total bacterial number(AODC) was 1.1x10^7cells ml^-1, 5 times higher than control aquarium after 25 days. The V_(max) and K_m values of extracellular enzyme activities were higher in the fish aquarium. Especially, the V_(max) of β-glucosidase in the fish aquarium was 7 times higher than in the control. These results suggest that the predation and digestion of Hypophihalmichthys molltrix should cause the diversification of substrates of extracellular enzymes and stimulate nutrient cycles and degradation of organic materials.

소양호에서 섬유소 기질에 부착한 미생물의 유기물 분해 활성도

최승익,안태석 ( Seung Ik Choi,Tae Seok Ahn ) 한국하천호수학회 1995 생태와 환경 Vol.28 No.1

In order to define the composition of dissolved organic materials(DOM) in the Lake Soyang, the cellobiohydrolase and, the β-glucosidase activity of attached bacteria on cellulose films submerged in various depths for 40-50 days were investigated. The numbers of the attached bacteria varied from 0.5×10^6 to 8.4×10^6 cells cm^-2, and the seasonal variation was more dramatic in epilimnion than in hypolimnion. The ranges of cellobiohydrolase and β-glucosidase activities were from 0.1 to 1396.5nM l^-1hr^-1 and from 0.2 to 2194.8nM l^-1hr^-1, respectively. Maximum activity of these two factors was recorded in winter. The specific activity of β-glucosidase was relatively higher during fall and winter compared to that of early spring. This results may indicate that the major component of DOM after the phytoplankton bloom is high molecular weight organic materials. But in early spring and summer, the DOM is low molecular weight organic materials.

산성물질로 처리한 호수물에서의 세균수와 활성도의 변화

최승익,김범철,안태석 ( Seung Ik Choi,Bomchul Kim,Tae Seok Ahn ) 한국하천호수학회 1997 생태와 환경 Vol.30 No.2

To scutinize the effects of acidification on bacterial community, bacterial numbers and β-glucosidase activities were analyzed within the acid-treated lake water. One liter of 0.2㎛ filtrated water of Lake Soyang were adjusted as pH 3.7, 5.0, 6.1 with 1N H-2SO_4 and inoculated to ml of Lake water. In case of pH 6.1, after incubating for 10 hrs, bacterial numbers and activities were similar to those of control. But in case pH 5.0, after incubating for 72 hrs, bacterial numbers and activities were higher than other cases. In low pH condition, pH 3.7, the bacterial community have not recovered their numbers and activities. Specific activity of β-glucosidase in pH 5.0 condition was the highest.

수생관속 식물이 우점하는 연못에서의 B - glucosidase 활성도 변화

안태석,정미정,최승익 ( Tae Seok Ahn,Mi Jeong Jeong,Seung Ik Choi ) 한국하천호수학회 1996 생태와 환경 Vol.29 No.4

For determing the ecological roles of free-living bacteria and epiphytic bacteria on marophytes (Acorus calamus, Nymphaea tetragona, Nymphoides indica), the β-glucosidase activities of free-living and attached bacteria were investigated at two ponds weekly from May, 1995 to August, 1995. The β-glucosidase activities of pond water of Yeonjeokji and Sesimjeong were ranged 35∼1073 nmol 1^-1 hr^-1 and 30∼898 nmol 1^-1 hr^-1, respectively. At Yeonjeokji, where the phytoplankton was abundance, the variations of β-glucosidase activity correlated with the chlorophyll a concentration, while at the Sesimjeong, where the macrophyte was abundance, the correlation between activity and chlorophyll a concentration was not appeared. The areal activity of A. calamus, N. tetragona, N. indica were varied 16∼437, 223∼149537 and 19∼2396 nM cm^-2 hr^-1, respectively. The lowest areal peaks of activities of three macrophytes were appeared during the flowering period. At Yeonjeokji, the specific activity of epiphytic bacteria on N. tetragona was higher than that of free-living bacteria during the late spring, but it was lower during the summer. In other hand, the specific activity of epiphytic bacteria on N. indica, was 200∼500 times higher than that of free-living bacteria. At Sesimjeong, variation of the specific activity of epiphytic bacteria on A. calamus was similar to that of free-living bacteria. These results suggest that bacterial mineralization rates are affected by the kind of macrophytes, their physicological state and limnological characteritics.

호수 생태계에서 살아있는 세균을 측정하기 위한 qDVC 방법의 적용

김미리,서은영,최승익,안태석,Kim, Mi-Ree,Seo, Eun-Young,Choi, Seung-Ik,Ahn, Tae-Seok 한국미생물학회 2006 미생물학회지 Vol.42 No.3

호소수내의 '살아있는 세균'을 측정하기 위하여 quantitative direct viable count (qDVC) 방법을 적용하였다. qDVC방법에 적용되는 최적 glycine 농도는 2%였으며, '살아있는 세균'을 계수하는데 있어서 평판계수법, CTC법 보다는 qDVC 방법이 보다 효과적이라는 것을 확인하였다. qDVC방법으로 '살아있는 세균'을 측정한 결과 다른 두 방법보다 $2.4{\sim}6.0$배 높은 값이었다. 또한 qDVC방법은 '살아있는 세균'을 죽은 세포 또는 휴면세포와 쉽게 구별할 수 있었다. For measuring the viable cells in lakes, quantitative direct viable count (qDVC) method is applied. In the qDVC process, the final concentration of glycine is fixed as 2%. For confirming the effectiveness of qDVC for enumerating the viable cells, the viable bacterial numbers were measured by plate count, CTC reduction method and qDVC method at 5 different lakes. Among these 3 methods, the bacterial numbers by qDVC is $2.4{\sim}6.0$ times higher than those by the other 2 methods. And by the qDVC method, the viable cells were easily discriminated from dead or dormant cells.

소양호에서 세균수와 세균 체적의 계절적 수심별 변화

안태석(Tae Seok Ahn),최승익(Seung Ik Choi),변명섭(Myeong Seop Byeon),박호완(Ho Wan Park) 한국하천호수학회 1998 생태와 환경 Vol.31 No.3

N/A

저농도 영양염류를 농축하는 여재에서 총인과 부착세균의 변화

김주영,남종현,정다운,조안나,최승익,안태석,Kim, Ju-Young,Nam, Jong-Hyun,Jung, Da-Woon,Cho, Ahn-Na,Choi, Seung-Ik,Ahn, Tae-Seok 한국미생물학회 2009 미생물학회지 Vol.45 No.2

비점오염원 관리를 위하여 영양염류 농축장치를 개발하였다. 이 장치는 저농도 상태인 영양염류를 고농도로 전환시키며, 이 과정에서 세균이 중요한 역할을 하고 있다. 세균은 장치 내 여재에 생물막을 형성하면서 영양염류를 농축하였다. 총인의 농축효율을 확인하기 위해 장치로 유입되는 하천수와, 유출되는 공극수, 여재에서 총인과 용존무기인, 총세균수를 측정하였고 농축과정에서 미생물 군집이 어떻게 달라지는가를 파악하기 위해 DGGE를 수행한 후 염기서열을 분석하였다. 총인의 경우 하천수에서는 0.12~0.35 mg/L로 농도가 낮았지만 농축 후 유출수에서는 0.45~0.86 mg/L, 여재에서는 40.91~242.71 mg/kg로 매우 높았다. 그러나 용존무기인은 농축이 일어나지 않았다. 총세균수 역시 하천수에서는 $0.3\sim2.3\times10^6$ cells/ml이었으나 농축 후 유출수와 여재에서 각각 $0.4\sim4.4\times10^6$ cells/ml, $0.8\sim1.9\times10^9$ cells/g로 높게 나타났으며, 총인의 농도 변화와 비슷한 패턴을 보여 총인의 농도와 세균수 간에 밀접한 관계가 있음을 확인하였다. 또한 세균의 군집은 하천수에서는 Clostridium 속이 주로 나타났으나 여재에서는 Aquabacterium 속이 우점하다가 천이가 일어나서 Clostridium 속과 Enterococcus 속이 출현하였다. 결론적으로, 영양염류 농축장치의 여재에서 부착세균의 생장으로 인하여 총인의 농축이 일어났음을 확인하였다. 따라서 이 농축장치는 총인을 고농도로 회수함으로써, 저농도로 다량 유입되는 비점오염원의 관리를 용이하게 할 수 있으며, 회수된 농축수는 수계에 추가적인 부하로 작용하지 않는 자연비료로서 활용할 수 있다. A nutrient-concentrating system was operated to retrieve total phosphorus efficiently from a non-point pollution source. Attached bacteria were expected to play an important role in the system. Phosphorous was concentrated by formation of bacterial biofilms on rubberized coconut fiber media of the system. While concentration of total phosphorus (TP) ranged merely 0.12~0.35 mg/L in the stream water, TP levels in pore water and the media were 0.45~0.86 mg/L and 40.91~242.71 mg/kg, respectively. Total bacterial number (TBN) ranged $0.3\sim2.3\times10^6$ cells/ml in stream water, $0.4\sim4.4\times10^6$ cells/ml in pore water and $0.8\sim1.9\times10^9$ cells/g in media. There was a close correlation between TP and TBN. Based on band profiles in DGGE analyses, bacterial communities in the media were different from that in the stream water. Clostridium spp. were abundant in the stream water while Aquabacterium spp. were dominant species in early stages of biofilm formation in the media. The genera predominant in matured biofilms of the media were Clostridium and Enterococcus.

파로호에 설치된 인공식물섬 식생기반재의 공극수에서 세균 분포와 체외효소활성도

김용전,허재규,남종현,김인선,최경숙,최승익,안태석,Kim, Yong-Jeon,Hur, Jai-Kyou,Nam, Jong-Hyun,Kim, In-Seon,Choi, Kyoung-Suk,Choi, Seung-Ik,Ahn, Tae-Seok 한국미생물학회 2007 미생물학회지 Vol.43 No.1

생태계가 파괴된 파로호에 수초대를 복원하는 방법으로 rubberized coconut fiber를 식생기반재로 사용한 인공식물섬을 2003년 8월에 설치하였다. 인공식물섬 식생기반재에서는 식물이 자랄 수 있을 정도로 영양염이 농축되어 꽂창포(Iris ensata), 노랑 꽃창포(Iris pseudoacorus), 갈대(Phragmites communis)등 식재된 식물이 잘 자랐다. 이 과정에서 세균의 역할을 알아보기 위하여 2004년 4월부터 10월까지 2주 간격으로 총세균수, 활성세균수, ${\beta}-glucosidase$, phosphatase를 조사한 결과 인공식물성 식생기반재의 공극수에서 각각 평균 $28.6{\times}10^{6}\;cells/ml,\;22.7{\times}10^{6}\;cells/ml,\;452.9nM/L/hr,\;16381.9nM/L/hr$로 조사되어 파로호 호수물보다 각각 10배, 15배, 22배, 38배 높았다. 그리고 영양염류농도는 총인과 충질소가 식생기반재 공극수에서 각각평균 1.06 mg/L, 12.5 mg/L으로 조사되어 호수물보다 12배, 3배 높았다. 이 결과 인공식물섬 식생기반재에서 새로운 생태계가 만들어졌으며, 이 생태계에서 세균이 중요한 역할을 하여 빈-중영양상태의 호수물에서도 식물이 잘 자랄 수 있었다. For restoration of disturbed ecosystem in Lake Paro, artificial floating island (AFI) was installed. Even though the lake water was oligo-mesotrophic, the macrophytes, such as Iris ensata, Iris pseudoacorus, Phragmites communis were growing well in the rubberized coconut fiber media. For elucidating this process, total bacterial numbers, active bacterial numbers and exoenzymatic activities of ${\beta}-glucosidase$ and phosphatase of pore water of media and lake water were analyzed. The average of total bacterial numbers, active bacterial numbers and exoenzymatic activities of ${\beta}-glucosidase$ and phosphatase were $28.6{\times}10^{6}\;cells/ml,\;22.7{\times}10^{6}\;cells/ml,\;452.9nM/L/hr,\;and\;16381.9nM/L/hr$ which were 10, 15, 22 and 38 times higher than those of lake water, respectively. Moreover, the total phosphorus and total nitrogen concentration of media showed high values of 0.82 mg/L and 7.0 mg/L, respectively, while those of lake water 0.07 mg/L and 2.3 mg/L. This results suggest that the bacteria was playing an important role for restoration of disturbed ecosystem with newly created microbial ecosystem in media of artificial floating island.

비점오염원으로부터 오염된 하천수에서 식물플랑크톤 배양을 이용한 영양염류 제거

조안나 ( Ahn Na Cho ),정다운 ( Da Woon Jung ),정유정 ( You Jung Jung ),최승익 ( Seung Ik Choi ),안태석 ( Tae Seok Ahn ) 한국하천호수학회(구 한국육수학회) 2009 생태와 환경 Vol.42 No.2

비점오염원으로부터 오염된 소하천에서 영양염류를 제거하기 위하여 식물플랑크톤 배양 장치를 설치하고 운영하였다. 식물플랑크톤 배양조에서 식물플랑크톤 정치배양 결과, 식물플랑크톤의 연속배양을 위한 배양조의 체류시간을 3일로 결정하였으며 TP는 70%, TN은 44%가 제거됨을 확인하였다. 연속배양 결과 45일 동안 배양조에 유입된 TP의 53.9%, TN의 53.1%가 식물플랑크톤에 의한 흡수와 슬러지로 제거되었다. 식물플랑크톤이 성장하면서 배양조의 pH와 용존산소농도는 각각 평균 10.8, 16 mg L-1이었다. 결국 비점오염원에 오염된 하천수의 영양염류는 식물플랑크톤의 사체와 화학반응으로 생성된 침전물로 제거되었다. 비교적 설치가 간단하고 경제성이 높은 식물플랑크톤 배양법의 높은 현장적용 가능성을 확인하였다. A phytoplankton cultivation system was installed and operated for removal of nutrients from stream water polluted by nonpoint source pollution. The system was a continuous-flow culture comprising a phytoplankton tank that received inflow from a storage reservoir. When the system was operated as a batch culture for the purpose of determining hydraulic retention time (HRT), the proper HRT value was three days, and the removal rate of TP and TN averaged 70% and 44%, respectively. When the system was operated with the continuous flow from a stream for 45 days, 53.9% of TP and 53.1% of TN were removed as sludge. Due to active growth of phytoplankton, pH and dissolved oxygen in the phytoplankton tank were extremely high, reaching 10.8 and 16 mg L-1, respectively. It was concluded that nutrients can be effectively removed from polluted stream waters by cultivating phytoplankton.