• 한국환경과학회지
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• 제10권2호
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• pp.159-166
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• 2001

We studied the appearance and proliferation of red tide organisms from March, 1998, to February, 1999, in the Jindong Bay. There were two red tide events during investigation, and we found that the dominant species Ceratium furca in May and Gymnodinium sanguineum in September, 1998. At surface, temperature and salinity showed 18.3~19.7$^{\circ}C$ and 30.6~30.9 psu in May and 25.6~27.$0^{\circ}C$, 28.0~28.5 psu in September, respectively. When the red tide occurred, the water mass stable. Dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphate(DIP) in Jindong Bay showed seasonal variability. In May, the nitrogen was a limited nutrient in which the ratio of DIN versus DIP was less than 16 (Redfield ratio), while in September phosphate. During June to September, 1998, phosphate acted as a limited nutrient due to the increased river run-off from land. In May, chlorophyll-a, dissolved oxygen(DO) and chemical oxygen demand(COD) showed higher than 20$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 5.0mg/$\ell$, respectively. In September, they showed in turns 100$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 10mg/$\ell$, respectively.

• 미생물학회지
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• 제29권6호
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• pp.361-370
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• 1991

Physical and chemical environmental factors influencing on the outbreak of freshwater red tide by Peridinium bipes (dinoflagellate) in Soyang Reservoir were studied. Red tide occured in the site of inflowing of tributary streams annually, but the extent and severity of red tide varied from year to year. Several environmental factors such as water level, nutrient releasing from sediment, cyst resuspension, and concentrations of $Ca^{2+}$ and $Mg^{2+}$were studiedin relation to development, extent, and duration of red tide. In June of 1989 and 1991, the red tides of Peridinium bipes were very severe, and these red tides coincided with notable and rapid drawdown of lake water in late spring. Nutrient releasing and cyst resuspension by turbulence during drawdown were suggested as main causes of red tide. The quanity of nutrient releasing from sediment and hydrometeorological factors such as run-off and wind may determine the extent and duration of red tide.

• ALGAE
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• 제22권3호
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• pp.241-246
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• 2007

Cochtodinium votykrikoides -related red tide is the most notorious tidal bloom, resulting in mass mortality to marineanimals. This study aimed to test the effect of C. polyknkoides on the lethality to Haliotis discus hannai under con-trolled conditions. The oxygen demand of C. polykrikoides increases to reach its peak duhng the night, while the oxy-gen usage by H. discus hannai was continuously decreased with a threshold of 2 mg L U. The addition of C.polykrikoides did not effect the respiration of the H. discus hannai. However, the usage of oxygen by C. polykrikoidesduhng the night may lead to anoxia in the animal. With aeration, the level of dissolved oxygen (D.O.) was between6.06 and 7.28 mg LU; 90% of abalones survived even with a high concentration of C. potykrikoides (9000 cells mL U).Without aeration (3 mg LU of D.O.), however, the H. discus hannai suffocated immediately. Once 20 hours hadelapsed, all of the abalones were dead. The density of the H. discus hannai population contributed to their mortality.Therefore, aeration during the night and maintaining lower abalone densities is the best way to promote the sur-vivorship of H. discus hannai during a C. polykrikoides red tide.

• Fisheries and Aquatic Sciences
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• 제6권2호
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• pp.66-73
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• 2003

To understand the physiology of a suspension-feeding bivalve and its potential impacts on the dynamics of red tides on tidal flats, rates of clearance and ingestion of Glauconome chinensis were measured as a function of algal concentration, when the bivalve was fed on a nontoxic strain of red tide dinoflagellate Prorocentrum minimum, Cochlodinium polykrikoides or Scrippsiella trochoidea. With increasing algal concentration, weight-specific clearance rate increased rapidly at lower concentrations and after reaching the maximum at ca. 0.2 to 1.0 mgC/L, it decreased at higher concentrations. Maximum clearance rate was nearly equal for different algal species and ranged between 2.1 and 2.6 L/g/hr. Weight-specific ingestion rate also increased at lower algal concentrations but saturated at higher concentrations. Maximum ingestion rate was 2 to 10 fold different with different algal species: S. trochoidea (10.1 mgC/g/hr), P. minimum (3.9 mgC/g/hr), and C. polykrikoides (0.99 mgC/g/hr). Nitrogen and protein content showed that S. trochoidea is the best among the tested three red tide dinoflagellates. The maximum filtration capacity, calculated by combining the data on ingestion rate from laboratory experiments and those from the field for the density of the bivalve and the red tide dinoflagellates was 4.7, 1.4, and 25.3 tons/m2/day for P. minimum, C. polykrikoides, and S. trochoidea, respectively. It is hypothesized that the abundant suspension-feeding bivalves in tidal flats can effectively mitigate the outbreak of red tides.

• 환경영향평가
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• 제12권5호
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• pp.341-348
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• 2003

Seasonal characteristics of water quality and effect of the freshwater discharge during open the tide embankment in Haechang Bay were evaluated. In the freshwater, where interior of the tide embankment, COD and Chl-a exceeded about 4mg/L and $10mg/m^3$, respectively, independent of season, while in the seawater they showed high values in April and July in contrast to the other period due to input of freshwater and increase of phytoplankton, respectively. The content of seawater inorganic nitrogen maintained a relatively high level at inner part of the bay, whereas high values of inorganic phosphorus content was distributed at all over the bay. The limiting factor for algal growth was nitrogen with respect to the N/P ratio. The compass of influence by the freshwater discharge in April was quite different with water pollutants. As a result of the salinity variation with time, the freshwater extended strongly to offshore from the surface layer without mixing with depth when open the tide embankment, and reached within about one hour at a station which is 3.5km from the tide embankment. To effective water quality management of Haechang Bay, discharge rate and pollutant loads should be controlled.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.324-327
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• 2006

This research is about the optical characteristic of red tide which is collected from Nam-Hae for basic research of red tide remote sensing technique development. 21 kinds of red tide organisms are cultivated to investigate optical characteristic of them on the level of laboratory, and chlorophyll specific absorption coefficient($a^*$) and backscattering coefficient($b_b^*$) are estimated by using spectrophotometer. Absorption spectrums according to species are appeared diversely from 0.005 to 0.06 (mg/ $m^2$), and the shapes of spectrums are also different. The range of $b_b^*$ are appeared $10^{-2}{\sim}10^{-4}$ mg/ $m^2$, which have around 100 times differences between species, and the shape of spectrum also have significant difference between species. These results are able to use as an input data of inverse model from ocean color.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.391-396
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• 2005

한국 연안 전 해역에 걸쳐서 매년 적조생물이 발생 한다. (1995년부터). 남해 중부 및 동부해역은 상습발생 지역이다 (7, 8월). 기상인자(기온, 수온, 강수량, 일사량, 일조시수, 바람)는 적조형성에 기여하며, 특히 수온 (기온)은 적조발생의 제한 인자로 작용한다. 수온 15$^{\circ}$C가 되는 일을 기점으로 적조발생에 소요되는 시간은 78${\sim}$104일 정도 걸리며, 누적일조시수, 누적수온, 누적강우량의 비교로부터 적조발생 해역을 구분할 수 있다. 즉, 남해중부 및 남해동부 해역은 고밀도 적조발생 해역이며 남해서부 해역, 동해남부 해역은 저밀도 적조발생 해역이다. 동해남부 해역을 제외한 나머지 해역은 수온 24.5${\sim}$25.5$^{\circ}$C의 범위에서 1000mg/l 이상의 밀도를 보이는데, 적조생물이 발생하면 대체로 수산피해를 가져다주는 적조경보의 범주에 든다. 위성원격탐사 기술로부터 우리나라 연근해 적조발생 해역 해황특성과 적조분포 상호간의 관계성으로부터 적조의 머무름과 이동은 냉수대의 발달 및 소멸 그리고 북상난류의 흐름과 밀접한 관계가 있음을 알 수 있었다. 또한 식물성플랑크톤의 농도의 변화를 이용하여 적조분포 해역의 감지가 위성위격탐사 기술로 가능하였다. GIS 기술을 통한 적조정보관리시스템의 구축으로 적조정보를 통한 공간분석이 가능하게 되었다.

• The Korean Journal of Ecology
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• 제9권3호
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• pp.149-160
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• 1986

Relationship between the causative organi는 of red-tide and environmental factors had been ecologically dealt wtih. The surveys were conducted at seven station in Jinhae Bay from July to September 1981. The water temperature and salinity had wide range, i.e. 23.3~29.3$^{\circ}C$ and 19G.78~31.29$\textperthousand$, but several chemical factors remarkably fluctuated; dissolved oxygen 102.9~210.4%, COD 2.10~8.96mg$O_2$/l, pH 8.1~9.4, $NO_3$-N trace~1, 052$\mu$g/l, $PO_4$-P 0.6~58.9$\mu$g/l and chlorophyll-a 2.18~290.5mg/$m^3$ in the observed area. The red-tide was mainly caused by two dinoflagellata taxa throughout major outbreaks occurred in July through September. Leading species of red-tide were Gymnodinium nagasakiense belong to the ajor species. During the surveyed period, cell nubers of the causative organisms of the red-tide extensively varied from 3${\times} /10^4$ cells/l to $1.5\times10^7 $cells/l with moths and stations; Prorocentrum spp. 0.3~12.5$\times\10^5$ cells/l in July; Gymnodinium nagasakiense 0.2~5.9$\times10^6 cells/l, 1.1~4.7$\times10^6$ cells/l, and 0.2~15.1$\times10^6$ cells/l in July, August, and September, respectively. Gymnodinium nagasakiense red-tide seemed to be caused by the high water temperature in summer, unusually low salinity due to heavy rains, and the concentrated nutrients for phytoplankton supplied with the municipal sewages from the urban areas and the wastewaters from the industrial complexes.

• 한국수산과학회지
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• 제29권2호
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• pp.165-173
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• 1996

무각류의 와편모조인 C. polykrikoides에 의한 적조는 맹독성으로 알려져 있으며, 이로 인한 어패류의 폐사로 매년 막대한 손실을 초래하고 있어, 어패류 폐사의 원인 독성분을 규명하고, 유용 조류로서 활용하기 위한 기초 자료를 얻을 목적으로 93년 10월 경남 통영군 욕지도 인근에서 발생한 적조시 채취한 천연 조체를 시료로 수종의 생리활성을 검색하였다. MeOH 추출물의 마우스 치사 독성은 없었으며 (지용성 획분 : 50mg, 수용성 획분 : 10mg), 미량 형광 HPLC 분석에서도 마비성이나 설사성 패류독은 검출되지 않았다. 또한, 5mg/ml의 농도에서는 어독성을 나타나지 않았으며, 항균성도 없었다 (10mg/disc). P-388 종양 세포에 대하여는 지용성 획분이 $180{\mu}g/m1$의 농도에서 $20\%$의 생육 저지활성을 나타내었고, 아미노산 분석에서 2개의 미확인 아미노산이 검출되었다. 용혈활성을 나타내는 성분은 지용성, 수용성 양 획분에 모두 존재하였으며, 지용성 획분중의 성분으로서는 EPA와 DHA가 동정되었고, 이들이 총지방산의 $40.6\%$를 차지하여 고도 불포화 지방산 자원으로서 이용 가능성을 시사하였다.

• 해양환경안전학회지
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• 제20권3호
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• pp.270-276
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• 2014

Seasonal characteristics of water and sediment qualities and potential effects of the freshwater discharge from a small tide embankment interior in a coastal area in Goheung county were investigated from May to September in 2012. Chemical oxygen demand values (COD) were mostly higher than 2 mg/L in summer ebb tide, which exceed the standard value of water quality criteria II of acceptable level for aquaculture activities. Nitrogen and phosphorus were found as the limiting nutrients for algae growth in summer and fall and in spring, respectively. Nitrogen was the limiting nutrient for diatom growth in the whole studied period. The sudden high values of COD, ammonia, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) were found in water sample collected from station 5 which located in front of the tide embankment sluice gate during spring ebb tide. The freshwater discharge form the tide embankment interior maybe affected the survey areas during a short time interval. Mean values of eutrophication index of the surveyed coastal region in spring, summer and fall were all bigger than 1. Water quality was mostly considered at level II which acceptable for aquaculture activities. Sediment quality in this study was generally in the range of standard for fisheries environment.