• Journal of Ecology and Environment
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• v.36 no.4
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• pp.407-419
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• 2013

Cyclotella species were collected at 51 sites from July 2010 to June 2013 in Korean coastal waters. A total of five Cyclotella species (C. atomus var. marina, C. baltica, C. litoralis, C. meduanae, and C. meneghiniana) were identified in this study. The diagnostic characteristics for five Cyclotella species are described, focusing on the spacing, position, number of satellite pores of the mantle fultoportula and valve face fultoportula. In addition, we put the salinity ranges of five species of Cyclotella together. Of the five Cyclotella species, C. baltica, C. litoralis and C. meduanae are newly recorded in Korea.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.391-406
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• 2013

A study on the fine structure of the genus Achnanthes species (Bacillariophyceae) is carried out at 92 stations for taxonomic purposes from January 2009 to April 2013 in Korean marine water, freshwater and brackish water. Twelve Achnanthes species are identified based on a variety of taxonomic characters by means of light microscopy and scanning electron microscopy. Of these, seven species, Achnanthes cocconeioides, A. groenlandica, A. javanica, A. kuwaitensis, A. parvula, A. pseudolongipes, and A. yaquinensis, are newly recorded in Korean waters. All 12 species are documented concerning a taxonomic key, description, distribution, seasonality, remarks and photographs. Twenty three Achnanthes taxa are identified in the survey.

• Korean Journal of Environmental Biology
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• v.30 no.3
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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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• v.30 no.2
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• pp.81-87
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• 2015

Recent studies have shown the importance of viruses as potential sources of plankton mortality, which affect primary production and biogeochemical functions of their hosts. Here, we report basic characteristics of a novel virus (Stephanopyxis palmeriana virus: SpalV) that causes lysis of a culture of the diatom S. palmeriana, which was isolated in Jaran Bay, Korea, in August 2008. SpalV is a round-shaped viral particle ~25-30 nm in diameter that propagates in its host's cytoplasm. In addition, it shows species-specific infectivity among the tested diatom species. The burst size and latent period are estimated to be roughly 92 infectious units $cell^{-1}$ and <80 h, respectively.

• ALGAE
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• v.32 no.3
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• pp.181-187
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• 2017

During a sampling at Nokdong harbor, southern coast of Korea in January 2017, the marine diatom Coscinodiscus wailesii cells infected by a novel parasitoid nanoflagellate were observed. While the development process of the trophosomes of the parasitoid was more similar to that of Pseudopirsonia mucosa, division pattern of the auxosomes was similar to that of Pirsonia species. Phylogenetic analyses inferred from 18S rRNA gene sequences revealed that the parasitoid infecting C. wailesii fell within the cercozoan groups and branched as a sister lineage of the clade consisting of Pseudopirsonia mucosa and the undescribed Cercomonas sp. SIC7235, with the sequence dissimilarity of 7.3% with Pseudopirsonia mucosa. All of these developmental and molecular characteristics suggest that the parasitoid nanoflagellate infecting the diatom C. wailesii is a new Pseudopirsonia species.

• ALGAE
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• v.23 no.3
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• pp.219-230
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• 2008

The structure of phytoplankton community was studied for one year round at 6 stations in the Beopsu Marsh, Haman-gun, Gyeongsangnam-do, Korea. One hundred seventy-eight taxa (69 taxa belonging to Chlorophyta, 55 taxa to Bacillariophyta, 33 taxa to Cyanophyta, 15 taxa to Euglenophyta, 2 taxa to Rhodophyta, 2 taxa to Dinophyta and 1 taxon to Xanthophyta) were observed. Phytoplankton bloom occurred at the staions 2, 3 and 4 where waters were polluted by sewage and treated water of purification plants from the vicinity. The species diversity index of phytoplankton was the lowest (0.66) in November at the station 3, which the station showed the most eutrophic water due to the diverse pollutants from surroundings of the marsh. For the whole seasons, Fragilaria sp. and Euglena sp. appeared in pollutant water at the station 3, while Cyclotella sp. and Pinnularia sp. inhabited in relatively clean water at the station 5. To reserve the natural treasure, the wetland should be more specially managed by a local governing institution.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.241-251
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• 2018

To find unrecorded diatom species, random materials were collected from the freshwater, brackish water, and coastal waters. Benthic and periphytic diatoms were sampled from twelve localities. Thirteen species belonging to eight genera are newly added to the national flora of diatom. In the intertidal areas, the five species are new to Korea, Anaulus minutus Grunow, Anaulus simonsenii Witkowski & Metzeltin, Eunotogramma laeve Grunow, Eunotogramma productum Grunow, and Nitzschia subcapitellata Hustedt. The following two species are new from brackish waters, Chamaepinnularia krookiformis (Krammer) Lange-Bertalot & Krammer and Cymatoneis ovalis Heiden. The following four species are new from mountain peatlands, Geissleria ignota (Krasske) Lange-Bertlaot & Metzeltin, Chamaepinnularia hassiaca (Krasske) Cantonati & Lange-Bertalot, Chamaepinnularia mediocris (Krasske) Lange-Bertalot and Pinnularia linearidivergens Kulikovskiy, Lange-Bertalot & Metzeltin. The following two species are new from river or streams, Cymbella hustedtii var. compacta Krammer and Cymbella stigmaphora ${\emptyset}strup$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.669-676
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• 2017

To understand the relationship between environmental factors and phytoplankton community structures and why early outbreaks of Cochlodinium polykrikoides occur in the inner bay of Korea, short-term investigations were conducted at 17 stations in the eastern part of the South Sea of Korea, with sessions every two weeks from July 7 to August 24, 2016. The water temperature increased from $22.3^{\circ}C$ in the first survey to $28.4^{\circ}C$ in the fourth survey, which was a rise of about $6.01^{\circ}C$. Salinity was relatively high at Stns. 8 13 in the inner bay. In the first survey, rainfall of about 150 mm was observed, so nutrients were supplied at a high level and a high concentrate of Chl. a was observed. Cryptophyta (Crpytomonas spp.) represented 58.3 % of the community, followed by Bacillariophyta at 33.8 %. In particular, at Stn. 5, Dinophyta Prorocentrum spp. accounted for a very high percentage, 32.2 %. In the second survey, low phytoplankton populations were observed, and Bacillariophyta (Chaetoceros spp.) accounted for 61.0 %. At Stn. 4, Skeletonema spp. showed high populations but did not appear at other stations even at a low density. In the third and fourth surveys, phytoplankton populations were very low. Bacillariophyta represented 78.0 % in the third study and 73.3 % in the fourth. Interestingly, although the appearance of C. polykrikoides was investigated at the beginning of the red tide in the coastal area, they were not observed inshore, implying that the likelihood of inflow by the germination of resting cysts was low for the inner bay during this study period. In addition, environmental characteristics such as salinity and nutrient presence were significantly different between sampling stations due to the existence of a semi-closed bay in the southern sea, resulting in dominant phytoplankton species and community composition differing in these short-term investigations.

• Journal of environmental and Sanitary engineering
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• v.5 no.2
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• pp.117-122
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• 1990

The Jido Pond system was investigated from April, 1979 through March, 1980, in respect of seasonal changes in physico-chemical factors: i.e., temperature, pH, DO, BOD, COD, $Cl^-, \; Mg^{++}$, alkalinity, detergent, $SiO_2, PO_4\;^{3-}, NH_4\;^+, NO_2\;^-, NO_3\;^-$, total N, OM and OC; phytoplankton community growth; and the ecosystem metabolism. The phytoplankton community was represented by 23 species belonging to Chlorophyta, Bacillariophyta and Cyanophyta; each sharing 11, 9 3 respectively. The Chlorophyceans dominated the phytoplankton community contributing 75% of the total ？미 counts. The ranges of biotic diversity indices were, d, 0.85~2.80; H, 1.10~2.40; c, 0.13~0/40; and 3, 0.56~0.90. The chlorophyll standing crop varied in between 0.043 and 0.385g/$\textrm{cm}^2$ surface area. The ranges of photosynthetic and respiratory rates were 0.36~4.50; and 0.10~1.40 $O_2$ mg/1/hr, respectively. The monthly areal net primary production varied from 23.9 to 305.1C g/$\textrm{m}^2$/month. The Eu of the net production seasonally varied in between 0.31 and 7.80%, and the annual mean was 2.44%. The annual turnover times of phosphorus and nitrogen were 20 and 3 days, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.59-75
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• 2012

The species composition of plankton is essential to understand the material and energy cycling within marine ecosystem. It also provides the useful information for understanding the properties of marine environments due to its sensitivity to the physicochemical characteristics and variability of water masses. In this study we adopted metagenomics to evaluate eukaryotic plankton species diversity from coastal waters off Busan. Characteristics of water masses at sampling sites is expected to be very complex due to the mixing of various water masses; Nakdong River runoff, Changjiang diluted water (CDW), South Sea coastal water, and Tsushima warm current. 18S rDNA clone libraries were constructed from surface waters at the three sites off Busan. Clone libraries revealed 94 unique phylotypes from 370 clones; Dinophyceae(42 phylotypes), Ciliophora(15 phylotypes), Bacillariophyta(7 phylotypes), Chlorophyta(2 phylotypes), Haptophyceae(1 phylotype), Metazoa(Arthropoda( 17 phylotypes), Chaetognatha(1 phylotypes), Cnidaria(2 phylotypes), Chordata(1 phylotype)), Rhizaria (Acantharea(2 phylotypes), Polycystinea(1 phylotype)), Telonemida(1 phylotype), Fungi(2 phylotypes). The difference in species diversity at the closely located three sites off Busan may be attributed to the various physicochemical properties of water masses at these sites by the mixture of water masses of various origins. Metagenomic study of species composition may provide useful information for understanding marine ecosystem of coastal waters with various physicochemical properties in the near feature.