• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.305-315
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• 1983

A survey was carried out from July to December in 1979 and 1982 for the investigation of oceanographic conditions and phytoplankton in Seogwipo coastal area. Although a peculiar coastal sea water is formed by in flowing of fresh water, this is developed mainly in summer and disappeared or weakened in its strength after November. However, this coastal sea water covers only the surface while in mid and bottom layer open sea water is approached to the coast. Therefore, coastal and open sea water appears simultaneously in narrow sea area. Mean values of nutrient concentrates on surface layer during investigating period were $3.72{\sim}16.34{\mu}g-at/l$ in silicate, $1.98{\sim}5.53{\mu}g-at/l$ in nitrate and $0.34{\sim}0.90{\mu}g-at/l$ in phosphate. These showed slight differences among places but in general coastal side were lower than open sea side. Phosphates which is the lowest in concentrates among nutrients in Seogwipo coastal area shows almost similar value with Jinhae Bay but higher than open sea water around 10 mile south of Seogwipo. In general, seasonal changes of nutrients in investigating period shows a tendency of the lowest in October, increasing in November, and again slight decrease in December. As a phytoplankton fauna, 48 species, 1 variety and 2 breeds of Diatoms, 29 species, 3 varieties and 1 breed fo Dinoflagellates, and 1 species each of Chroococcus and Trichoceratium were found. Monthly predominant species are all neritic: Rhizosolenia sp. and Ceratium sp. in August, Chaetoceros sp., Ceratium sp. and Peridinium sp. in September, Astrionella sp. and Peridinium sp. in October, Astrionella sp., Navicula sp. and Chaetoceros sp. in November Among these, Rhizosolenia alata f. gracillima in August and Astrionella gracillima in November are remarkable predominant.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.328-334
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• 2005

Dinoflagellates were investigated from the coastal waters of Korea. The total 100 thecate dinoflagellates taxa, comprising of 93 species five varieties and two forms were identified, which were attributed to four orders nine families, 13 genera in Korean coastal waters. 22 species, two varieties and two forms were new to Korean waters. Ceratium arcticum, C. longirostrum, C. praelongum, C. tripos var. ponticum, Gonyaulax jollifei, G. pavillardii, Protoperidinium cassum cassum, P. conicum f. asamushi, P. depressum var. parallelum, P. elegans f. granulatum, P. globifera, P. incognitum, P. majus, P. mite, P. obtusum, P. pallidum daedalum, P. parvum, P. perplexum, P. pyriforme pyriforme, P. pyrum, P. sphaeroides, P. subsphericum, P. valgus, P. venustum, Diplopsalopsis orbicularis, Gotoius abei were new record species for Korea.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.167-176
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• 1995

A study on phytoplankton community was carried out from June, 1992 to May, 1993 at selected stations in Hoedong Reservoir. The phytoplankton are identified as 176 taxa including 5 phylum, 67 genera. The important species in this reservoir were Asterionella formosa, C meneghiniana, Dictyosphaerium plilchellum, Fragilaria crotonensis, Melosira distans, M grantulata, M. granulata var. angustissima, M. granulate var. angntissima f. spirdis, Micractinium pussillum, Microcystis aeruginosa, Pundorina morn, Pediastrum boryanum, P. duplex, Peridinium sp., Scenedesmus quadriauda, Synedra acus, S. rumpens and S. ulna. The causative species of water bloom were identified as Microcystis aeruginsa, Trahellomonas hispida, Ceratium hirwdinella, Peridinium sp., Melosira italica, Staurastrum dorsidentiferum var. onatum in the area. During the study periods standing crcps of phytoplankton were maximum in August, 1992 and minimum in December 1992. The species dominance index and diversity index were ranged 24.7-99.9, 0.001-3.06, respectively. Key Words : phytoplankton community, causative species of water bloom, standing crops. dominance index, species diversity index.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.275-280
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• 1998

In order to clarify the seasonal composition and abundance of zooplankton commuuty In Macheon Bay. the study was carried out trimonthly during the period from April 1996 to January 1997. 1 species of Cnidana. 1 species of Annelida, 2 Ima of Moiluscs.3 species of Rotifera, 4 species and 4 larspecies was Tintinnopsis beroidea In the spring, Copepodite In the summer, Tintinnopsis beroidea In the autumn and Ceratium risus In the winter. Abundance of zooplankton ranged firom 4.720 to 41,215 Inds./1 It was high In the summer (41,215 inds./l) and low In the spring 14,720 inds./l). Dominant index ranged from 0.133 (in the spring) to 0.551 (in the winter). Species diversity inden ranged from 1.114 (in the winters to 1.996 (in the spring).

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.225-227
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• 2001

출현한 식물플랑크톤은 82속 135종이었고 이중 Chrysophyta가 36속 63종(46.7%)로 가장 많이 출현하였다. 생태학적 주요종으로는 Aulacoseira granulata 등의 출현빈번종, Achnanthes longipes 등의 해수종, Actinastrum hantzschii var. fluviatile 등의 오수지표종 그리고 Ceratium furca등의 적조원인종이 출현하였다. 현존량은 1,000 ${cells/\ell}$ ～ 3,103,000 ${cells/\ell}$이었다. 우점종의 천이는 봄에 Pandorina morum, 여름에 Microcystis aeruginose, 가을과 겨울에 Oscillatoria tenuis, 겨울과 봄에 Phormidium tenue로의 천이양상을 보였다. 우점도지수는 0.34 ～ 0.94였고 종다양도지수는 0.5 ～ 2.57이었다. 오탁지수는 평균 2.4로 조사되어 $\beta$-중부수성 수역에 해당하였다. 유사도지수에 의한 집괴분석의 결과, 정점 1이 한그룹 그리고 정점 2, 3, 4가 한그룹, 정점 5가 한그룹으로 크게 3그룹으로 분석되어졌다.

• 한국해양학회지
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• v.25 no.2
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• pp.106-116
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• 1990

The dynamics and seasonal succession of dinoflagellate community, and their correlations with environmental parameters were investigated during the period from April, 1986 to March, 1987 at 6 selected stations in Masan Bay, Korea. The dinoflagellate standing crops varied extensively with months and stations: ranging from 44 to 2,789,900 cella/ l at surface layer and from 52 to 165,714 cells/ l at bottom layer, respectively. The distribution of standing crops by size class of dinoflagellate species showed that a group of 20-um size class was predominant throughout the present survey, since the most of dominant species have belonged to the size category. Among dominant species, Gyrodinium fissum was most dominant throughout the year in all sampling stations, particulary in June. Scripsiella trochoidea was predominant in May, Protoperidinium bipes and Prorocentrum minimum from June to September, Prorocentrum triestinum, P micans and Ceratium fusus from September to December, and Heterocapsa triquetra from December to April. The stepwise multiple regression analysis between dinoflagellate and environmental parameters revealed that salinity, nitrate-N, pH, and transparency were correlated with the variations of standing crops of dinoflagellate.

• Journal of Aquaculture
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• v.15 no.1
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• pp.61-68
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• 2002

A comparative study on the effect of rearing depths at 2 (surface) and 5 (bottom) m on growth of the scallop was undertaken in Nam-myeon coastal area during June to December, 1997. There were very little difference in the levels of temperature (12.2 ~24.5$^{\circ}C$), salinity (27.3 ~33.1$\textperthousand) and dissolved oxygen (>7.05 mg/l) at a given month. But the chlorophyll level fluctuated between 1.2 and 11.0 $\mu g/l$ at the surface but below 2 $\mu g/l$ at the bosom. Highest phytoplankton density occurred in August and Ceratium dominated it during the period from June to October. Mean growth of the bay scallop at surface and bottom for the six months rearing period was as follows; 0.19 and 0.16 mm/day for shell height, and 0.16 and 0.12 g/day for total weight. Maximum predicted values of shell height calculated by von Bertalanffy growth model were 52.62 mm for the surface and 46.73 mm for the bottom reared scallop. Survival of the scallop was higher (80 %) for the surface group than that at the bottom (60%).

• Journal of Aquaculture
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• v.15 no.3
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• pp.123-129
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• 2002

In Nam-myeon coastal area of southern sea, Korea, the following hydrobiological conditions prevailed during 1997: water temperature: 12.6 ~24.5 $^{\circ}C$ ; Salinity: 27.32 ~33.$10 \textperthousand$, Dissolved oxygen: 7.05 $ml/L$ and Chlorophyll a: 1.69 ~ 7.40 $\mu $/L. Phytoplankton, dominated by Ceratium sp, peaked during June-July. Mean growth rates of the bay scallop of selected and non-selected groups cultured for 185 days in this area from July to December, 1997 were 0.17 and 0.19 mm/day for shell height, and 0.17 and 0.16 g/day for total weight, respectively. Maximum predicted values of shell height, calculated by von Bertalanffy growth model, were 54.98 mm for the selected and 52.62 mm for the non-selected groups. Survival of the selected and non-selected groups was 80.0 and 87.0%, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.459-471
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• 1991

The community structure and micro-scale distribution of plankton in relation to hydrography were investigated in Masan Bay, Korea in October 1989. Warmer and less saline waters with stratification was located in the inner part of the Pudo Strait, and chlorophyll-a and nutrients were higher. Both phytoplankton biomass and nutrients was changed dramatically around the Strait. Offshore/oceanic species in phytoplankton i.e., Chaetoceres decipiens, Rhizosolenia stolterforthii, Rhizosolenia styliformis and Ceratium trichoceros and zooplankton i.e., Sagitta enflata, Oncaea uenusta and Oikopluera longicaudata occurred mainly in well mixed waters of the outer part. This suggests that discontinuous layer seems to play an important role as an approximate border for the plankton population. This layer was located between Station 3 and Station 4 near the Pudo Strait, since the layer consisted of a series of micro-scale discontinuties of salinity and dissolved inorganic nutrients gradient. Phytoplankton patchs of more than 801e1 were found only in the inner part of the bay. Depletion of silicate caused by a rapid assimilation of phytoplankton in the inner part of the bay seemed to be responsible for the decline of blooms.

• 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$\textperthousand$.