• The Korean Journal of Ecology
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• 제20권1호
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• pp.61-68
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• 1997

Due to its lack of wave action and tide ecosystem in Inchon dock lacks in marine characteristics. Structural condition in the dock is artificially similar to that of lake. The purposes of this study was to clarify the water quality, to provide the basic physicochemical data and tl resolve the causation of ？미 blooming. Samples were obtained monthly from four stations in Inchon dock during January to December, 1991. Water temperature ranged from $2.7^{\circ}C$ to $27.6^{\circ}C$ under the strong influence of air temperature. Salinity varied between 24.7%-30.4% thus being influenced by freshwater discharged from a spring. Dissolved oxygen was concentrated from 0.1-13.92 mg/l and suspended solids were 6.9-231.0 mg/l. The physicochemical factors were similar to those investigated 10 years ago. However, increased concentration of nitrogenous nutrients initiated ？미 blooming and its process was accelerated to reach eutrophication. Algal blooming was proceeded in March and August.

• 대한환경공학회지
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• 제39권10호
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• pp.556-560
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• 2017

Microcystis sp.로 수화된 원수에 대해 전염소 처리시 발생하는 문제점과 응집보조제로 polyamine을 투입하였을 때의 응집 및 여과공정에서의 효과를 수중의 입자상 물질의 분포로 평가하였다. Microcystis sp.로 수화된 원수를 전염소 처리하면 Microcystis sp. 군집이 각각의 세포들로 분산되어 응집에 불리한 것으로 나타났다. 응집보조제로 polyamine을 이용하면 응집제 단독으로 응집하는 경우에 비해 탁도와 입자성 물질 제거에 효과적이었으며, 특히 직경 $5{\mu}m$ 이하의 입자상 물질의 제거에 탁월하였다. Microcystis sp.로 수화된 상수원수를 이용하는 정수장에서는 전염소 처리를 배제하고 정수장을 운영하는 방법이 후단공정에서 입자상 물질의 제거 및 관리에 효율적이었다.

• 생태와환경
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• 제55권2호
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• pp.111-119
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• 2022

충주호의 지류인 제천천 하류에서 주기적으로 발생하는 남조류 과다증식의 현황과 오염원을 분석하였다. 2015년 10월 18일과 2016년 9월 25일에 제천천 하류의 명서낚시터지점(GPS; 37°03'25.5"N, 128°03'13.6"E)에서 클로로필 a의 농도는 각각 399.2, 184.8 mg m^-3이었으며, 남조류독소인 microcystins의 농도는 각각 124.09, 79.71 ㎍ L^-1이었다. 명서낚시터 지점에서 남조류 과다증식은 충주호의 수위 및 수위변화와 매우 밀접한 관계가 있는 것으로 나타났다. 즉 수온이 남조류 성장에 적합한 조건에서 충주호 수위가 상승하여 수체가 정체되는 시기에 남조류 과다증식이 발생한다. 제천천에 위치한 환경부의 수질측정망 자료를 분석한 결과, 제천하수종말처리장이 위치한 장평천이 주요 오염 지류인 것으로 나타났다.

• Ocean and Polar Research
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• 제25권3호
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• pp.303-314
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• 2003

The initiation of Cochlodinium polykrikoides blooming in the South Sea of Korea occurs in the sea near Naro-Do in late August. In this paper, the relationships of this annual occurrence with the environmental conditions are presented. In early summer, the winds in the sea near Naro-Do are southwesterly and the upwelling occurs in the near-shore area. The favorable winds to the upwelling are relaxed in August and the downwelling favorable northeasterly winds set in around late August. The change of wind direction causes the onshore transport of warm-and-fresh off-shore water into the sea near Naro-Do and a front between near-shore water and off·shore water is formed. Along the front, downwelling occurs and the environmental conditions for the diatom become unfavorable. When the typhoon and storm bring well-mixed East China Sea water into the sea near Naro-Do in September, the conditions for the dinoflagellates become unfavorable and blooming of C. polykrikoides disappears.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.95-100
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• 1998

The purpose of this study is to describe the change of the spring bloom and oceanographic condition. The variation of pigment concentration derived from the satellite ocean color data has been analyzed. According to the movement of blooming area, blooming was very concerned with a rising trend of sea surface temperature and a supply of nutrients. A nutrient rich water carried by the Oyashio encounters with the warm Core ring, where mixings and blooms are observed. We examined the correlation by using the satellite observations of the temperature and chlorophyll-a for the spring seasons (May, June, July) of 1998 the off Sanriku area (38-43N, 141- l50E). Using the SeaWiFS data, we process the data into the level-3, which contains the geophysical value of chlorophyll-a. And chlorophyll-a data is mapped for the water between 110E and 160E, and 15N and 52N with a 0.08 * 0.05 degree grid for each image. And Sea Surface Temperature (SST) data is produced using the AVHRR onboard the NOAA. The SST is derived by the MCSST. Then, the data is mapped for the water as much as chi-a data. And these gridded image was made by detection of each water masses, which are Kuroshio Extension, the warm-core ring and the Oyashlo Intrusion, etc., using those satellite images to determine short term change. Off Sanriku is a place where warm-water pool and the Oyashio at-e mixed. When warm streamer has intruded in cold water, the volume of phytoplankton increases at the tip of warm streamer. Warm water streamer was trigger of occurring blooming. And also, SeaWiFS images provided as much information for the studies of chlorophyll-a concentrations in the surface.

• 한국환경과학회지
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• 제25권7호
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• pp.937-950
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• 2016

Algal blooming in 4 major rivers introduces substantial impacts to water front activity. Concentrations of algae are increasing at major points along the Geum River. Ecosystem food webs can be affected by algal blooming because blue-green algae release toxic materials. Even though there have been many studies on blue-green algae, its causality to environmental factors has not been completely determined yet. This study analyzed the exclusive correlation between various hydrometeorological, water quality, and hydrologic variables and the cell number of cyanobacteria to understand causality of blue-green algae in the Geum River. A prewhitening process was introduced to remove the autocorrelation structure and periodicity, which is useful to evaluate the effective relationship between two time series.

• 생태와환경
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• 제44권2호
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• pp.113-128
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• 2011

본 연구는 2007년 10월부터 2008년 7월까지 대청호의 중요 유입지천인 소옥천에 대해 이화학적 수질, 식물플랑크톤 군집을 분석하고 수질영양단계를 평가하였다. 식물플랑크톤은 Microcystis aeruginosa와 Aulacoseira granulata 등 수화원인종의 출현빈도가 높아 잠재적으로 남조류 및 규조류에 의한 녹조현상이 연중 지속될 수 있을 것으로 판단된다. 또한 Oscillatoria limasa를 포함한 10분류군의 오염수역 지표종이 출현하였다. TSI (Trophic Status Index)와 LTSI (Lake Trophic Status Index)에 의한 수질영양단계 평가 결과, TSI는 중부영양~부영양화단계, LTSI는 중부영양단계~과영양단계로 평가되었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 12th Asian Congress of Fluid Mechanics
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• pp.82.6-83
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• 2008

• 유기물자원화
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• 제21권3호
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• pp.93-98
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• 2013

본 연구에서는 최근 자주 거론되는 녹조발생의 주요 원인을 찾아보고자 하였다. 지난 십년이상의 기상자료 및 수질에 대한 실측자료를 이용하여 녹조원인에 대한 통계적 접근을 시도하였다. 팔당호를 대상으로 한 연구에서 조류예보일수에 일정한 추세를 발견할 수는 없지만 발생년도에는 10일 이상씩 나타나는 특징을 보여 주고 있으며 최근 5년간은 발령일수가 증가하고 있어 주의해야 할 것으로 판단되었다. 유속의 자료 대신 사용된 방류량을 보면 조사기간 중 세 배 정도의 차이가 나는 해도 관찰되었다. 클로로필a에 대한 다른 지표들의 상관계수를 보면 뚜렷한 한 가지 지표로 나타나지 않아서 상관계수 0.4를 넘는 요인은 없었다. 그 중 중요한 요인으로 나타나는 것은 일조시간, BOD, 그리고 방류량이며 일조시간과 BOD는 양의 상관 그리고 강수량과 방류량은 음의 상관을 나타내고 있어서 광합성미생물에 의한 현상으로서 타당한 결과로 보였다. 수온과 총인농도는 중요한 요인이 될 것으로 예상되었으나 결과는 낮은 상관성을 보였다. 이상의 결과로 판단할 때 조류발생에는 여러 가지 요인이 복합적으로 작용하며 그중 일조시간, BOD, 그리고 유속 또는 방류량은 중요한 요인으로 판단된다. 방류량과 다른 요소와의 상관관계도 조사하였다. 강수량과 수온이 양의 상관을 보이는 것은 계절적인 효과로 타당해 보였다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 추계학술발표회
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• pp.187-188
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• 2007

The fluctuations of biochemical and molecular activities III the harmful dinoflagellate, Cochlodinium polykrikoides, depending on water temperatures, were studied. In genomic DNA concentration, a similar value of 0.6 was shown at $12^{\circ}C$ and $15^{\circ}C$, but significantly increasing DNA from $18^{\circ}C$ (p<0.05), with a maximum of 1.8 at $24^{\circ}C$. After$24^{\circ}C$, the DNA significantly decreased to 0.6. Likely, the concentrations of RNA and total protein were at their highest values of 1.7 and 0.07 g $mL^1$ at $24^{\circ}C$, respectively. In contrast to ONA, RNA and total protein began to increase at $15^{\circ}C$. Oxygen availability between lower and higher temperatures was significantly different and increased from $18^{\circ}C$ according to light intensity, regardless of wavelengths (p<0.05). At $24^{\circ}C$, the highest value of the maximum electron transport rate (ETRmax), ranging from 537.9 (Ch 1) to 602.5 mol electrons $g^{-1}$ Ch1 a $s^{-1}$ (Ch 4), was also shown. Nitrate reductase (NR) and ATPase activities were at their highest values of 0.11 mol $NO_2^-g^{-1}$ Ch1 a $h^{-1}$ and 0.78 pmol 100 $mg^{-1}$ $at^2$ $4^{\circ}C$, respectively. When the cells cultured at $15^{\circ}C$, NR and ATPase activities significantly increased compared to $12^{\circ}C$ (p<0.05). In an analysis of CHN, the concentration of C and N also significantly increased (p<0.05). However, at $27^{\circ}C$, most of the molecular and biochemical movements were much lower, compared to $24^{\circ}C$. These results suggest that C. polykrikoides is very sensitive biochemical and molecular activities depending on water temperatures. Possibly, it is desirable to estimate at $18^{\circ}C$ the initiation of the massive blooming development of C. polykrikoides. In nature, it will be very difficult to maintain the massive blooms after $24^{\circ}C$ because of the possibility of significantly decreasing the molecular movement and activity of C. polykrikoides.