• ALGAE
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• 제23권3호
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• pp.187-199
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• 2008

A study on the fine structure of the marine diatom Thalassiosira has been carried out during the periods from January 2007 to March 2008 in Korean coastal waters. As the third series of the Thalassiosira species, a fine structure, description, distribution and taxonomic remarks of the six Thalassiosira species were observed by means of light microscope and scanning electron microscope. The critical features of Thalassiosira species were a shape of external tubes of marginal strutted processes and labiate process. Six species showed each different shape of external tubes, marginal strutted processes and labiate process. The shape of external tube was divided into five types: T shape of Thalassiosira curviseriata, small-rounded shape of T. lundiana, double-layer form and flame shape of T. nordenskioeldii, tulip shape of T. punctigera and tooth-shape of T. tenera. This external character may be able to key character for positive identification of the Thalassiosira species. Of these Thalassiosira lundiana, T. minuscula and T. tenera were new records for Korean coastal waters.

• 한국해양학회지
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• 제21권3호
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• pp.184-192
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• 1986

1982년 2월부터 1986년 2월까지 한국 연안역에서 출현한 부유성 규조류중 Thalassiosira속의 소형종에 대하여 주사전자현미경 등을 이용한 미세구조를 연구하 였다. 이 결과 Thalassiosira속 4종을 동정하여 기재하였으며, 그중에서 Thalassiosira weissfiogii, T. minina, 및 T. oestrupii var. venrickae 등 3종을 한국 산 미기록종으로 보고한다.

• 한국해양학회지
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• 제22권3호
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• pp.179-190
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• 1987

1983년 9월부터 1987년 3월까지 韓國沿岸域에서 출현한 浮游性 주조류 중 Thalassiosira 屬의 소형종에 대하여 走査電氣顯微鏡을 이용하여 微細構造를 연구하 였다. 第2부로서 Thalassiosira aestivalis, T.allenii, T.binata, T. Conferta, T. pacifica 및 T. rotula 등 6종을 同定.記載하였으며, 이중 Thalassiosira allenii, T.binata와 T. Conferta는 韓國産 未記錄種으로 보고 한다.

• ALGAE
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• 제25권3호
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• pp.121-131
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• 2010

Thalassiosira species were collected from October 2007 to January 2009 in an attempt to better understand species diversity of the genus Thalassiosira in Korean coastal waters. A total of 5 Thalassiosira species (T. concaviuscula, T. oceanica, T. partheneia, T. simonsenii and T. nanolineata) were identified here. Most species in this study were of small size, and 5 species were recorded for the first time in Korean coastal waters. Using a scanning electron microscope (SEM), we described distinctive characteristics of fine structure that proved to be important diagnostic characteristics for the identification of each species. The most important diagnostic characteristics for Thalassiosira species identification were the marginal strutted processes, the position of labiate processes, and the areolation. The differential characteristics of the species studied were: T. concaviuscula has a double layered external tubes on the marginal strutted processes; T. oceanica shows marginal ridges that are interlinked between the marginal strutted processes; the valve face of T. partheneia is fairly convex and its labiate process is positioned midway between two strutted processes; T. simonsenii is characterized by two labiate processes and somewhat coarse areolae; and, T. nanolineata has several central strutted processes and linear areolation.

• Ocean and Polar Research
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• 제27권2호
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• pp.149-159
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• 2005

결론적으로 전체 식물플랑크톤과 소형식물플랑크톤의 생체량이 높았던 2월에는 규조류 S. costatum과 Thalassiosira spp.가 우점하였으며 특히 내측해역에서 높은 농도를 보였는데 이는 2월의 낮은 수온과 내측해역의 풍부한 규산염에 의한 영향으로 판단된다. 5월에는 전체 식물플랑크톤과 소형식물플랑크톤이 상당히 감소하였는데 이는 영양염의 감소 특히 인산염 제한에 의한 것으로 사료된다. 5월에는 미소형식물플랑크톤의 기여율이 높게 나타났고 규조류 Rhizosolenia spp.와 Pseudo-nitzschia spp.가 우점하였으나 2월에 비해 낮은 chlorophyll a 농도를 나타내고 있으며 이는 낮은 농도의 영양염 특히 DIN:DIP와 Si:DIP의 분포를 통해서도 알 수 있듯이 인산염의 농도가 크게 작용한 것으로 판단된다. 담수 유입으로 인해 내측해역의 염분이 낮았던 7월에는 소형식물플랑크톤이 평균 58.4%의 기여율을 보였으며, 미소형식물플랑크톤은 평균 32.6%의 기여율을 보여주고 있다. 또한 내측해역에서 monad type의 phytoflagellate와 남조류 Oscillatoria spp.가 우세하였고 외측해역에서는 S. costatum이 우세하게 나타났다. 9월에는 7월과 마찬가지로 염분이 낮은 내측해역에서는 미소형식물플랑크톤의 기여율이 높았으며 monad type의 phytoflagellate가 우점하였고 외측 해역에서는 소형식물플랑크톤의 기여율이 높았으며 규조류 Chaetocems spp.가 새로운 우점속으로 출현하였다. 이와 같이 아산만의 환경적인 변화에 따라서 우점속의 변화를 가져왔으며 이런 우점속의 변화는 식물플랑크톤 군집의 계절적 변화를 나타내었다. 본 연구결과는 식물플랑크톤 군집에 대한 연구가 부족했던 아산만의 식물플랑크톤 역학을 이해하는데 기여할 것으로 기대된다.

• 한국지구과학회지
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• 제36권2호
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• pp.190-197
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• 2015

남극 브랜스필드 해협의 동부분지로부터 획득한 GC08-EB01 코어퇴적물의 고해상 엽층리로부터 규조를 이용하여 고기후변화를 연구하였다. 규조 정량 분석의 결과 규조 개체수 농도는 $0.4-4.2{\times}10^8g^{-1}$로 매우 풍부하게 산출되었으며, 엽층리는 생물기원의 규조가 풍부한 층과 육성기원 퇴적물이 풍부한 층으로 구분된다. 규조 엽층리는 Corethron crilophilum, Eucampia antarctica, Fragilariopsis curta, F. kerguelensis, Odontella weissflogii, Proboscia inermis, R. styliformis, Thalassiosira antarctica와 Chaetoceros resting spores 등의 번성이 특징적이며, 육원성 엽층리에서는 규조 군집이 혼합되어 나타나는 것이 특징이다. 홀로세 후기 동안 Fragilariopsis curta+F. cylindrus)/Thalassiosira antarctica의 산출 수직 분포비가 급격히 증가하는 구간은 해빙의 확장을 지시하며, 연구 코어 GC08-EB01 코어퇴적물이 퇴적되는 동안 적어도 5번의 한랭기가 있었음을 알려준다.

• Journal of Ecology and Environment
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• 제37권4호
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• pp.225-229
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• 2014

Feeding behavior of Temora turbinata was investigated through laboratory experiments with special emphasis on its food preference and consequent clearance rate on diatom and microbial components given as common natural food assemblage of coastal area (Uchiumi, Uwa Sea, Japan). Among available prey items, T. turbinata showed the highest clearance rate for Thalassiosira spp. ($0.23{\pm}0.08L\;Temora^{-1}day^{-1}$) followed by Chaetoceros spp. ($0.11{\pm}0.03L\;Temora^{-1}day^{-1}$), but clearance rates for other diatom, Nitzschia spp. was lower (0.03 to $0.07L\;Temora^{-1}day^{-1}$). Bacterial abundances showed no response against 24-h feeding of T. turbinata. Feeding of T. turbinata on heterotrophic nanoflagellates (HNF) was apparent when clearance rates of T. turbinata on diatoms were relatively low, but T. turbinata did not consume HNF as well as ciliates with Thalassiosira spp. of which clearance rate was highest. The results suggest that HNF and ciliates are possible supplementary prey item for T. turbinata, but their contribution as food sources can be limited by the presence of other prey items such as preferable diatom species.

• 환경생물
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• 제30권3호
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• pp.245-271
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• 2012

A study on the indigenous diatoms was carried out at 103 sites during August 2008 to April 2011 from the marine and the brackish waters in Korea. A fine structure of small-sized diatoms was examined using a light and scanning electron microscopy. Sixty species of diatoms were newly identified and composed of 3 class, 6 subclass, 16 order, 21 family and 39 genus. The detailed nomenclatures, references, photographs and distributions were here reported. Of 60 species, the most frequent species was Tryblionella coarctata appearing 24 times, and 22 times followed by Thalassiosira lacustris, Cocconeis stauroneiformis was 20 times. In the level of genus, Chaetoceros, Parlibells and Thalassiosira were included 4 species, Actinocyclus, Minidiscus and Licmophora were included 3 species. This study will provide the knowledge of the diversity level of diatom in Korea, the knowledge is important on the diatoms for further studies.

• ALGAE
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• 제18권4호
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• pp.361-363
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• 2003

This study was conducted at Seomjin River estuary to identify the causative species of algal bloom and their blooming cycles. Field surveys were conducted at 4 stations in every week from April to December of 1999. Thirty species were observed as the causative species of alga bloom. Skeletonema costatum, Thalassiosira sp., and microflagellate spp. (mixed red tide: Chroomonas sp. and two species of Prasinophycea) made algal blooms during the present study period. In addition, toxic algal species of diatom Pseudo-nitzschia multiseries and dinoflagellate Dinophysis acuminata were observed. The algal blooms were caused by microflagellate spp. in June, Thalassiosira sp. in July and Skeletonema costatum in August. Generally, the algal blooms persisted for about 5 days in this area.

• ALGAE
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• 제24권2호
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• pp.67-77
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• 2009

The marine phytoplankton diatom Thalassiosira species are described from the Korean coastal waters, based onobservations of Fine structutre of its frustules. As a fourth series, this study deals with 5 Thlassiosira species (T. decip-iens, T. ecgentrica, T. mala, T. nodulolinmta, and T. proschinae). The most striking features of these species are also theform and position of two processes on frustules. There is a central strutted process on valve face except T. nodvlolin-eata, which has a modified one on its center. The extemal tubes of marginal strutted processes are divided twoforms: "pile" form in T. decipiens and T. proschkinae, "short straw" form in T. eccentrica and T. nodulolineata. T. maladoes not present the extemal tubes in valve margin. The labiate processes are located in valve margin except T.proschkinae, which has it on valve face. Of theae, thrce species (T. mala, T. nodulineata at a final contentration of 5%and T. proschkinae were newly recorded in the coastal waters of Korea.