• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.604-621
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• 2017

This research was conducted to find the indigenous diatom species unrecorded in Korea from February to December 2016. The samples were taken at 28 sites of the coastal regions on the west coast of Korea and Jeju Island. Diatoms were collected mostly from sand and mud of tidal flats, including gravel, seaweed on the bottom and macrophytes floating in the seawater. Diatom specimens were observed by means of light and scanning electron microscopy. Twenty one species were discovered and added as new specimens to the Korean diatom flora, which are divided into 9 orders, 12 families, and 16 genera. The list and photographs of the species are included with the description of the morphological characteristics and distribution in Korea.

• Fisheries and Aquatic Sciences
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• v.26 no.7
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• pp.423-436
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• 2023

The objectives of this review were to synthesize the community structure of phytoplankton and the role of atelomix in the phytoplankton dynamics in Ethiopian highland lakes. Changes in a lake's physical structure, light dynamics, and availability of nutrients are closely associated with phytoplankton ecology, and phytoplankton assemblages provide insight into phytoplank- ton responses to these environmental changes. Based on the available information, a total of 173 species of phytoplankton are grouped under seven classes, Chlorophyceae (80 taxa), Bacillariophyceae (55 taxa), Cyanophyceae (24 taxa), Dinophyceae (6 taxa), Eugleonophyceae (6 taxa), Xanthophyceae (1 taxon), and Cryptophyceae (1 taxon) were recorded in five different tropical Ethiopian highland lakes. Chlorophyceae and Bacillariophyceae dominated in terms of species composition. Partial atelomixis, seasonality, and low nutrient concentrations seem to be the main drivers in structuring phytoplankton composition and abun-dances in Ethiopian highland lakes, characterized by a high diversity of atelomix-dependent benthic diatoms and desmids. Thus, this review will help understand the role of atelomix and nutrient availability in the phytoplankton composition and biomass of tropical highland lakes of Ethiopia.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.05a
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• pp.70-70
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• 2002

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.31-31
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• 2004

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.10a
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• pp.166-168
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• 1999

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.126.2-126
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• 1997

No Abstract, See Full Text

• 한국해양학회지
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• v.18 no.2
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• pp.91-103
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• 1983

Qualitative and quantitative phytoplankton samples collected during a cruise in the southeastern sea of Korea in September 1981, were analysed. A total of 185 species of phytoplankters were identified in the present study. Of the numbers 14 species of diatoms and 56 dinoflagellate forms were found. The rest were 3 silicoslagellate forms, a cryptomonad and a euglenoid each. On the bases of the analyses of the phytoplankton communities, two vegetation areas were recognized. It is demonstrated that the extent of each vegetation area largely depends on hydrographical features. In southeastern coastal waters, the vegetation was fairly rich, and consisted of small celled diatoms and minute flagellates. In the northern part of the area, abundant phytoplanktons were present consisting of various diatoms and dimofalgellates. The size of standing stock of phytoplankton was compared with hydrography and the specific composition of phytoplankton. The importance of mixing between the Tsushima warm current water and North Korean cold water in distributing phytoplankton stocks was stressed.

• ALGAE
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• v.19 no.3
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• pp.217-226
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• 2004

The present study is to examine the water quality and to analyze the plank tonic and benthic phytoplankton communities at 6 stations in the Dong River and its tributary streams of Kangwon Province from November, 2001 to March, 2002. During the studies, water temperature ranged from 3.5 to 12.8℃; pH, 6.5-7.9; DO, 9.29-11.36 mg·l^(-1); BOD_5, 0.20-2.38 mg·l^(-1); TN, 1.2842-3.1871 mg·l^(-1); TP, 0.0052-0.0576 mg·l^(-1); and SS, 0.85-9.62 mg·l^(-1). The standard of water quality according to the Korean Environmental Preservation Law showed the first class except St. 6 through the survey. Six taxa of plank tonic phytoplankton identified were poor flora in November, 2001. The representative species frequently observed were the diatoms Achnanthes lanceolata, Achnanthes minutissima, Cymbella minuta, Cymbella parva, Diatoma vulgare, Fragilaria construens, Gomphonema pervulum, Navicula cryptocephala, Nitzschia palea., Scenedesmus sp. of green algae and Stephanodiscus hantzschii. Monthly dominant species of phytoplankton were Achnanthes lanceolata and A. minutissima in both February and March, 2002, but the blue-green algae, Oscillatoria sp. and the diatom, Stephan discus hantzschii were predominant at some stations in March. Phytoplankton standing crops ranged from 9.84 ${\times}$ 10$^3$ to 3.56 ${\times}$ 10$^4$ cell·l$^{-1}$ in November and 1.68-2.99 ${\times}$ 10$^5$ cell·l$^{-1}$ in February, while it changed 4.52-8.01 ${\times}$ 10$^5$ cell·l$^{-1}$ at St. 1, 2, 3 and 1.03-1.71 ${\times}$ 10$^6$ cell·l$^{-1}$ at St. 4, 5, 6 in March. Benthic phytoplankton communities was composed of 38 taxa in November, 31 taxa in February and 23 taxa in March. It showed a contrary tendency to planktonic phytoplankton diversity. Benthic diatoms which were more than 25% of the total populations were Cymbella turgida, Diatoma vulgare, Cocconeis placentula, Navicula cryptocephala var. intermedia in November; Achnanthe lanceolata, Cocconeis placentula, Achnanthes minutissima in February; and Achnanthes lanceolata and Cyclotella meneghiniana in March.

• ALGAE
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• v.18 no.2
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• pp.135-143
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• 2003

The seasonal dynamics of phytoplankton and trophic state were evaluated weekly at three sites in the Lake Unmoon from May to November 2001. The seasonal succession pattern of phytoplankton community in the Lake Unmoon showed that the dominant species were; i) diatoms during the late spring, ii) dinoflagellates in June, iii) blue green algae, diatoms and dinoflagellates in July, iv) green algae and blue green algae in August, v) blue green algae in September and early November, and vi) diatoms in November. Members of Microcystis were dominant from middle August to late October and members of Aulocoseira appeared as important species in autumn in the Lake Unmoon. The concentration of chlorophyll-a ranged from 2.4 to 23.0 mg ${\cdot}m^{-3}$ (average: 8.6 mg ${\cdot}m^{-3}$) during the study period. Concentrations of total phosphorus were high during the period from July to November with the maximum of 0.028 mg ${\cdot} l^{-1}$. The average N/P ratio was 121, indicating that concentrations of phosphorus may determine the high algal biomass in the Lake Unmoon. Concentrations of silicate were higher in the Lake Unmoon (average value: 10.016 mg ${\cdot}$ l-) than in other lakes (average values: 1.074-4.408 mg ${\cdot}$ l-), suggesting high potential of diatom growth. The average trophic state index in the Lake Unmoon was 52, which was close to eutrophic state, and the trophic state trend was increasing steadily since 1999.

• Ocean and Polar Research
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• v.42 no.3
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• pp.249-261
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• 2020

This study details grain-size distributions (GSDs) of carbonate and biogenic opal fractions of the sediments retrieved from the South Korea Plateau in the East Sea and draws paleocanographic implications from them. The opal-fraction GSDs show fine modes of 10.3 ㎛ and coarse modes of 102.5 ㎛ on average. The fine-mode grains of opal fractions mainly consist of small diatoms and radiolarians including their broken frustules, while the coarse-mode grains are mostly comprised of large warm-water diatoms and radiolarians. Significant positive correlation between opal contents and abundances of the coarse-mode GSDs in the total GSDs suggests that the abundances of the coarse-mode GSDs were controlled by the increased surface productivity of warm-water diatoms during interglacial stages. The carbonate-fraction GSDs show fine modes of 2.4 ㎛ and coarse modes of 99.1 ㎛ on average. The fine-mode grains mainly consist of coccolithophores, while the coarse-mode grains are mostly comprised of intact or broken planktonic foraminifera. The abundances of coarse-mode and fine-mode GSDs were not correlated with carbonate contents, suggesting a complex control exerted by both the degree of carbonate dissolution and the productivity of coccolithophores on the carbonate-fraction GSDs.