• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.333-344
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• 1982

Major species of zooplankters were idcentified from the specimens collected from Lake Ok-Jeong for 1 year period and the descriptions are given together with the list of tile species and some drawings. Assuming from the dominant species present in the lake, the Lake Ok-Jeong is considered to be a fairly progressed eutrophlc lake. For a few species, some Questions are presented in taxonomical and biogeographical view points.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.2
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• pp.247-253
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• 2004

Major species of Lake Deganuma has varied depending on the season. Namely, there are Micractinium pusillum, chlorella., Scenedesmus sp. shown up in spring season, Microcystis aeruginosa, Microcystis wesenbergii, Anabena spiroides in summer and autumn season and Cyclostephanos invisitatus, Diatoma in winter season in the Lake. As the number of plankton increased, the zeta potential on their surface of them decreased. For this reason, they were dispersed in the lake though the population increased. Zeta potential of M. aeruginosa showed -20mV when their outer size got smaller. As for coagulant dosing in DAF, large amount of coagulant was effective to get lots of sludge during water treatment.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.11a
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• pp.42-48
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• 2001

A kinetic model was presented to estimate the uptake/release rate constants and thereafter, bioconcentration factor, $k_1$, $k_2$ and BCF (bioconcentration factor), for the uptake of PH by plankton were obtained. Implies that PH(petroleum hydrocarbon) caused no significant influence on the uptake of $N-NO_3$, but significant influence on that of $P-PO_4$. In addition, the application of kinetic model for the bioconcentration of volatile organic toxic compound by organism suggests that the uptake of PH by plankton was an important process for the environmental capacity of PH.

• Journal of Species Research
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• v.8 no.4
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• pp.365-372
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• 2019

We have conducted faunistic study of sea lice collected from marine plankton samples of western and southern coasts of Korea. These specimens were identified as Caligus undulatus Shen and Li, 1959, belonging to family Caligidae and order Siphonostomatoida with worldwide distribution. The range extension of C. undulatus is reported in addition to the previously known distributional range from the Northwest Pacific (China, Japan, and Korea), India, Brazil, and Mexico. This species can be distinguished from all previous reports with characteristics such as overall body proportions of both sexes, structure details of mouth appendages, armature of legs, and some variation in body size. The distributional range of C. undulatus is now given with its northern and south hemisphere limit being 40 to $10^{\circ}N$ in the Indo-Pacific and $30^{\circ}S$ in the Southwest Atlantic. This is the first record of its female occurring in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.2
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• pp.69-78
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• 1974

A study on the contents of dissolved oxygen and phytoplankton in the pond water has been carried out to determine the water quality and to investigate the cause of red water in fish ponds at Pusan Fisheries College in 1972-1973. The results obtained are as follows : 1. Measured oxygen content during the period from 6th to 7th of August 1972 was: 23.95ppm ($328\%$ in saturation rate) in daytime and 0.39 ppm($5\%$) in the early morning in the water which contains heavy bloom of phytoplankton, on the other hand, in clear water the range of oxygen content was 8.72 to 6.58ppm. 2. The occurrences of red water in 1972-1973 were always caused by the sudden death of Synechocystis aquatilis (Cyanophyta) when the water temperature was very high ($30-33.5^{\circ}C$) and then high mortality of fish under rearing followed. 3. The phytoplankon observed during this study period was 133 species belonging to 55 genera in 23 families, and those of Chlorophyta was dominant in number of species, and Cyanophyta in quantity. 4. Zooplankton observed was 12 species belonging to 11 genera in 11 families, and they were very small both in number of species and in quantity compared to those of phytoplankton.

• Ocean and Polar Research
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• v.28 no.1
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• pp.57-65
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• 2006

Various marine plankton were observed in the ballast water of vessels entering Incheon and Busan harbors. The ballast water of which age ranged from 2 to 54 days originated from the coastal waters of New Zealand, Taiwan, Singapore, Japan, Hong Kong and Pakistan, and from the Pacific Ocean. The total number of marine plankton taxa in 9 ballast tanks of different ships was 170: 90 phytoplankton, 24 protozoa and 56 zooplankton. The most diverse taxonomic groups were diatoms in phytoplankton, ciliates in protozoa and copepods in zooplankton. Classifying the specimens by size, above 50% of the number species of phytoplankton belonged to the size range between 50 and 150 Un. Protozoa and metazooplankton were found frequently in the size range between 50 and $120{\mu}m$ and 500 and $1,000{\mu}m$, respectively. The relationship between the species number and the age of ballast water was not significant. This is because of difference of filtration amounts derived from discordance of collecting samples. Among plankton observed in ballast water, some harmful algae and non-indigenous aquatic species were identified. Therefore, we need to investigate whether these species can inhabit in Korean coastal waters in further study.

• Journal of Environmental Science International
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• v.11 no.8
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• pp.793-800
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• 2002

Butyltin (BT) compounds were measured in seawater, sediment, sediment core, settling solids, and plankton from Gwangyang Bay in 2001, Tributyltin (TBT) was detected in seawater from 1 out of the 7 seawater sampling sites and in sediment from 18 out of the 35 sediment sampling sites. The highest concentration of TBT was found in the sediment from the site near Yeosu Harbor (53 ng Sn/g dry wt), acting as the point source for TBT The mean concentrations of TBT were in the order of plankton> settling solids> sediment. The degradation indexes ([DBT]+[MBT]/[TBT]) for the plankton were less than 1, indicating the possibility of recent inputs of TBT. The indexes for the sediment and settling solids ranged from 1.14 to 8.73. The composition of the BT compounds found in the settling solids was similar to that found in the sediment. The vertical profile of the total BT compounds in the sediment was characterized by an abrupt decline from the surface. However, no butyltin compounds appeared below a depth of 10 cm, corresponding to the 1980s. Accordingly, the current results demonstrated that the levels of all butyltin species in the environment of Gwangyang Bay were relatively lower than those in other polluted coastal areas. The vertical profile also suggested a fairly recent history for the down-core.

• Ocean and Polar Research
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• v.34 no.2
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• pp.201-218
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• 2012

The purpose of this study is to investigate climatological variations from the sea surface temperature (SST), chlorophyll-a concentration (Chl-a), and phytoplankton size class (PSC), using NOAA AVHRR, SeaWiFS, and MODIS data in the South Sea of Korea (SSK) and East China Sea (ECS). 26-year monthly SST and 13-year monthly Chl-a and PSC data, separated by whole and nine-different areas, were used to understand seasonal and inter-annual variations. SST and Chl-a clearly showed seasonal variations: higher SST and Chl-a were observed during the summer and spring, and lower values occurred during the winter and summer. The annual and monthly SST over 26 years increased by $0.2{\sim}1.0^{\circ}C$. The annual and monthly Chl-a concentration over 13 years decreased by $0.2{\sim}1.1mg/m^3$. To determine more detailed spatial and temporal variations, we used the combined data with monthly SST, Chl-a, and PSC. Between 1998 and 2010, the inter-annual trend of Chl-a decreased, with decreasing micro- and nano-size plankton, and increasing pico-size plankton. In regional analysis, the west region of the study area was spatially and temporally correlated with the area dominated by decreasing micro-size plankton; while the east region was less sensitive to coastal and land effects, and was dominated by increasing pico-size plankton. This phenomenon is better related to one or more forcing factors: the increased stratification of ocean driven by changes occurring in spatial variations of the SST caused limited contributions of nutrients and changed marine ecosystems in the study area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.483-494
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• 2019

From the cosmopolitan superiority of the as the first world map completed in 1402 with surprisingly detailed images and contents on the Africa Continent it is reasonable to think that the Koreans in early fifteen century were already with highly up-to-date perspectives on the universe and world history and cultures. However, some 490 year later the first phytohydrographic plankton investigation in the neritic seas of Korea was performed by a Japanese company with sampling points covering from Tokyo Bay through Jeju neritic waters to Shanghai estuary, which was in turn preceded by the first oceanographic investigation other than the simple mapping Koreans seas by using two French sailboats. The first phytohydrographic plankton investigation in Korean seas were behind the world first oceanic plankton exploration, the German Plankton Expedition, by 25 years. Starting from the oceanographic investigation including phytohydrographic samplings in the whole Yellow Sea in 1915 the full-scale phytohydrographic plankton studies were tried in Korean seas which is well represented by the 1921 oceanographic investigation on the whole East Sea with 80 sampling stations. In 1932 two separate oceanographic investigations followed, one in the East Sea where 78 stations from Busan to southern Sakhalin Island were simultaneously visited by 50 research vessels for the physical, chemical, and biological oceanographic studies, and the other one in southern coast and western East Sea of Korea where ocean current observation as well as plankton sampling were made in 120 stations to understand the relationship between the ocean current and plankton distribution in the region. In 1933-1934 more intensified investigations on phytohydrography were carried out particularly in the East Sea as an integral part of the basic marine ecosystem studies for the Myeong-Tae (Alaska Pollock) resources estimation. Scientists' attitude for the marine investigation and research activities seemed to be almost unchanging even to the year 1943, which could be reflected by the fact that publication of the results from the investigations performed in 1945 were finally done in 1967 at Tokyo. Some 70 years later from the mid-twenty century we might be standing on the turning-point of "need to be prepared" for the new era of changing paradigm by reviewing, archiving, and analyzing the prior information big data from the previous ocean observation and biohydrographic investigations. At the same time each professional societies for the above mentioned sciences might trigger a continuous project to reorganize and update the records on related bibliography and its history every 30 years.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.4
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• pp.283-291
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• 2012

The present work reviews some mechanism explaining how thin layer can develop in the near coastal zone. The existence of thin layer was observed by physical research methods later than classical biological approaches. The Richardson number, which is a ratio between the stratification and shear stress is crucial factor determining the occurrence of thin layer. Micro-structure turbulence seems to affect the plankton behavior, in particular the encountering rate. Encountering rate affects significantly feeding, reproduction etc. and this fact was proved by the mechanical simulation methods. Recently the Gyrotaxis was introduced to explain how thin layer occurs in the mixing layer. Such physical approaches to explain ecological problem will be prominent methods for marine ecological research area.