• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.196-197
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• 2000

한국 남해 중앙부에 위치하는 나로도 연안해역은 대규모 적조 형성으로 막대한 수산피해를 발생시키고 있는 Cochlodinium polykrikoides 적조의 매년 첫 발생해역으로 관심이 모아지고 있을 뿐만 아니라(국립수산진흥원, 1998), 주변해역의 수괴 확장정도에 의해 복잡한 해양환경 특성을 나타내는 곳이기도 하다(양 등, 1999). 따라서 본 해역의 해양환경 및 생물분포는 시·공간적으로 매우 다른 특성을 나타낼 것으로 판단되어, 본 연구에서는 이른봄 나로도 인근해역의 해양환경 특성 및 식물플랑크톤 군집의 분포에 영향을 미치는 환경요인에 대하여 고찰한다(윤과 박, 2000). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.244-245
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• 2001

육상 환경과 인접해 있는 연안해양환경은, 그 변화 특성이 매우 독특하며 복잡하게 나타난다. 해양환경 변화에 큰 영향을 미치는 것 중에는 해류와 조류 등과 같은 유체의 운동의 역할이 크다. 특히 바람과 같은 기상환경인자는 해표면의 유체의 운동에 큰 영향을 주게 되며, 이로 인하여 유체내의 입자물질(적조생물, 유류 등)의 집적 및 확산에 결정적인 영향을 끼치게 된다. 우리 나라는 계절풍이 뚜렷하게 나타나는 지역이지만, 지역에 따라서는 주변 지역과의 기압배치 및 지형적인 요인등에 의해서 그 특성이 충분히 변할 수 있다. 이러한 지역적인 국지풍은 만과 같은 소규모 지역에서 큰 영향을 끼칠 것으로 생각된다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.211-212
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• 2001

최근 연안어장의 환경오염, 양식생물의 생산력에 막대한 타격과 인간의 건강에 해로운 적조 (red tide)의 빈번한 발생으로 많은 관심이 부각되고 있다. 우리나라 연안에서 발생한 적조현상은 '80년때까지는 대부분 1주일정도 지속되었으나 최근에는 2주일 이상 그리고 '95년도에는 Cochlodinium polykrikoides가 2개월이나 지속된 바 있다. 이러한 현상은 매년 같은 시기에 발생하여 양식장 및 육상 축양장에 심각한 경제적 피해를 주고 있다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.523-530
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• 2020

Based on the results of harmful algal blooms (HABs) monitoring by the National Institute of Fisheries Science and local governments, the effects of changes in the marine environment on HABs are described. Since the beginning of HABs monitoring in 1972, they continued to increase from the 1980s to the 1990s. After the largest number of HAB incidents (109) in 1998; the trend declined until the 2010s. Most HABs in the 1970s were caused by diatoms. In the 1980s, coastal dinoflagellates caused HABs; Cochlodinium polykrikoides blooms have been occurring continuously since 1993. There are three HAB species that cause damage to fisheries in Korea. The high-density bloom of Karenia mikimotoi caused mass mortality in shellfish in Jinhae Bay in 1981. Karenia sp. blooms occurring around Tongyeong in 1992 killed aquaculture fish. Since the occurrence of the largest fisheries damage of KRW 76.6 billion in 1995 caused by C. polykrikoides blooms, they have been occurring continuously. The concentration of nutrients in coastal waters was the highest in the 1980s and has declined since the mid-1990s. This reduction in nutrient concentration is a good explanation for the decreasing number of HABs. Since 2016, a summer high water temperature of 30℃ or more has appeared, and the range and scale of C. polykrikoides blooms have been greatly reduced. In 2016, K. mikimotoi blooms occurred around Wando, Jangheung and Goheung and small scale blooms of C. polykrikoides occurred around Yeosu. There were no C. polykrikoides blooms in 2017; however, Alexandrium affine blooms occurred from Yeosu to Tongyeong. There was a small-scale blooms of C. polykrikoides in 2018 compared to those in the previous years. Our results show that reduction in nutrients and the high water temperature owing to climate change are a good explanation for variation in HABs in Korean coastal waters.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.382-382
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• 2000

Pseudo-nitzschia 속은 현재까지 알려진 유독 적조생물 중 규조류로서 유일하게 독성을 가지는 종이며, 생활사가 짧기 때문에 영양염 공급이 충분하거나 수온 등 환경조건만 적당하면 언제든지 수 일 이내로 대규모 적조를 형성할 수 있다. 지금까지 분리된 종은 P. pungens, P. multiseries, P. cuspidata, P. delicatissima, P. subfraudulenta, P. subpacifica, P. multistriata로 그 중에서 P. multiseries가 기억상실성 패독인 domoic acid (DA)를 생성하는 종이지만, 형태적으로 P. pungens와 매우 유사하여 전자현미경의 형태로서 구분되기 때문에 본 종을 신속 탐색하기 위하여 전세계적으로 많은 연구를 하고 있는 실정이다. 특히 P. pungens와 P. multiseries는 대체적으로 동시다발적으로 4월과 10월에 일시적으로 발생하고 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.446-447
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• 2001

Cochlodinium polykrikoides는 1995년에는 전남 고흥군 연안에서 발생한 적조는 동의 강릉연안까지 광범위한 해역에 발생하여 750여억 원의 엄청난 재산상의 피해를 가져 왔다(Kim et al., 1997). Cochlodinium의 생태적인 특징과 관련된 어류패사 기구에 대한 연구에 의하면 Cochlodinium이 분비하는 점액성분에 의한 호흡곤란과 질식(Lee, 1996), 유해활성산소와 관련된 산화적 반응에 따른 아가미 기능 저하(Kim et al, 2000) 및 독성물질에 의한 폐사(Onoue et al., 1985; Yuki and Yoshimatsu, 1989) 등이 보고되었으나, 아직까지 명확한 폐사 원인은 구명되지 않았다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.155-159
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• 1999

Marine bacteria inhibiting the growth of the diatom, Chaetoceros calcitrans were screened from seawater samples collected at south coast of Korea in 1996. Six strains were isolated from those samples. Among them, a bacterium SR-14 strain had the strongest inhibition activity against the alga. The selected SR-14 strain was identified as an Alteromonas sp. (supposed to be Alteromonas colwelliana) according to its biochemical results. Alteromonas sp. SR-14 was able to grow in raw seawater, aged seawater, Conwy medium for culture of microalgae and C. calcitrans culture filtrate. The host ranges of Alteromonas sp. SR-14 were C. calcitrans, C. muclleri and C. negracile among 10 species of diatom. All of the Chaetoceros spp. tested were inhibited by the Alteromonas sp. SR-14, However, the growth of the other genera in Bacillariophyceae was not inhibited.

• Journal of Life Science
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• v.17 no.11
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• pp.1453-1463
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• 2007

This study presents a molecular phylogenetic analysis of the harmful dinoflagellate Cochlodinium polykrikoides, by use of partial sequence of small subunit (SSU) rRNA gene from most of the major taxa(24 species) in dinoflagellates. The class Dinophyceae clade formed a strong monophyletic relationship with C. polykrikoides and several taxa. On the basis of deeper nodes, the phylogenetic relationships placed C. polykrikoides closer to the order Prorocentrales rather than to the order Gymnodiniales, which was supported by a strong bootstrap value (100%) in the analyses of Neighbor-Joining and Parsimony methods. There is strong support for C. polykrikoides being placed in the same branch as Gymnodiniaceae and being connected in a clade with Prororcentrum micans among Prorocentrales. Morphological data show that C. polykrikoides is well associated with the genus Gyrodinium; however, this species is genetically closer to Gymnodinium than to Gyrodinium. The placement of C. polykrikoides always formed an independent branch separated from other dinoflagellates. In conclusion, planktonic P. micans plays an important role as an ancestor of Gymnodinium, whereas C. polykrikoides appears to be used an intermediate position between P. micans and Gymnodinium based on evolution.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1996.06a
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• pp.232-235
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• 1996

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.271-278
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• 1999

In order to clarify water quality, dynamics and structure of phytoplankton communities, and red tides, the present study was carried out monthly from July to September 1998 at 19 stations in Deukryang Bay. Water temperature varied from 24.$0^{\circ}C$ to 28.6$^{\circ}C$, and salinities ranged from 25.0$\textperthousand$ to 28.6$\textperthousand$. During red tides in July, chlorophyll-$\alpha$ contents were rather high in August, it showed that phytoplankton controlled primary production in this bay. Phytoplankton was composed of 89 diatoms, 19 dinoflagellates, and 3 silicoflagellates. Phytoplankton standing crops varied from a minimum of 1.3$\times$10$^4$cells/ι(Sept., St. 17) to a maximum of 3.8$\times$10$^{6}$ cells/ι (July, St. 10). Red tides occurred in July when the standing crops averaged 1.8$\times$10$^{6}$ cells/ι. Leading the causative organisms of red tide were Prorocentrun minimum in the upper bay, Chaetoceros curvisetus in the mouth and middle part of the bay, Ceratium furca and Thazassio- sira sp. around Nokdong Harbour. Concentration of nutrients such as nitrogen was high in the upper bay, during red tides, water temperatures varied from 23.8$^{\circ}C$ to 29.7$^{\circ}C$ and salinity were 23.l$\textperthousand$ to 27.0$\textperthousand$.