• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.143-150
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• 2000

Assuming that summer surface waters in the South Sea (northern East China Sea) are formed mostly by a mixing of three source water (Changjiang Discharge Water; Kuroshio Water and Yellow Sea Surface Water) we apply optimum multiparameter (OMP) analysis to calculate the mixing ratio of each source water to a given surface water. Since OMP requires more parameters than the number of water types (three in this study), we utilize two radium isotopes of dissolved $^{226}Ra\;and\;^{228}Ra$ along with temperature and salinity. Parameter values of each source water are deduced from in situ and historical data. Results with three source of waters on the surface waters are quite promising with less than $1\%$ of unanswered portions. Results not only reproduce the measured temperature and salinity faithfully but also discern the water masses of similar T and S according to their source water mixing. Extending OMP analysis to a whole water column obviously requires more parameters because more source waters are involved in the water mass formation. Original OMP routine utilized dissolved oxygen and nutrients. However, they seem to be perturbed too much by biological activities in the case of shallow waters. We discussed the use of other potential parameters. Also the benefit of parameter substitution is briefly introduced for the future OMP application on shallow waters.

• 수산해양기술연구
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• 제34권1호
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• pp.52-61
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• 1998

We studied behaviour pattern of anchovy (Engraulis japonicus) shoal by a method of shoal echo integration and tested species identification by a method of artificial neural network using the acoustic data collected in the East China Sea in March 1994 and in the southern coastal waters of the East Sea of Korea in March 1995. Between areas, frequency distribution of 10 shoal descriptors was different, which showed characteristics of shoal behaviour in size, bathymetric position and acoustic strength. The range and mean of shoal size distribution in length and height was wider and bigger in the southern coastal waters of the East Sea than in the East China Sea. Relative shoal size of China Sea. Fractal dimension of shoal was almost same in both areas. Mean volume reverbration index of shoal was 3 dB higher in the southern coastal waters of the East Sea than in the East China Sea. The depth layer of shoal distribution was related to bottom depth in the southern coastal waters of the East Sea, while it was between near surface and central layer in the East China Sea. Principal component analysis of shoal descriptors showed the correlation between shoal size and acoustic strength which was higher in the southern coastal waters of the East Sea, than in the East China Sea. Correlation was also found among the bathymetric positions of shoal to some degree higher in the southern coastal waters of the East Sea than in the East China Sea. The anchovy shoal of two areas was identified by artificial neural network. The contribution factor index (Cio) of the shoal descriptors between two areas were almost identical feature. The shoal volume reverberation index (Rv) was showed the highest contribution to the species identification, while shoal length and shoal height showed relatively high negative contribution to the species identification.

• 수산해양기술연구
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• 제47권2호
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• pp.99-107
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• 2011

The relationships among long-term variation in catches of Spanish mackerel (Scomberomorus niphonius) and main food organism such as common mackerel (Scomber japonicus), anchovy (Engraulis japonicus), and oceanic condition in Korean waters were analyzed using 40 years of time-series data from 1971－2010. In the 1990s, oceanic conditions around the Korean peninsula shifted to a warmer regime with higher SST (sea surface temperature). The total catch of Spanish mackerel in Korean waters increased dramatically since the early 2000s, and main fishing ground form into South Sea in winter season from December to January. From the results of correlation analysis, we found a significant relationship between the Spanish mackerel catch and environmental factor such as SST, common mackerel and anchovy catch in Korean waters.

• 한국환경과학회지
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• 제12권3호
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• pp.257-263
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• 2003

Oceanographic features around Korean waters related to the global change were studied by analysis of the longterm variation of water temperature, dissolved oxygen, sea level of the surface layer with 1$^{\circ}C$ temperature, spatial position of the subpolar front in the East Sea/Japan Sea (the East sea hereafter) and the Wolf Sunspot Number. With the global warming, the temperature of Korean waters has been increased 0.5∼1.0$^{\circ}C$ for 33years (1968∼2000). In case of the dissolved oxygen in the East Sea has been decreased 0.46$m\ell$/$\ell$. Year to year vertical fluctuations of the monthly anomalies of the surface layer with 1$^{\circ}C$water in the East Sea have predominant periods with 15years as the longterm variation of Arctic climate, 12 and 18years as the El Nino-Southern Oscillation. Spatial position of the subpolar front in the East Sea moved to northern part of the sea from the southern part of the sea with the increasing sea surface temperature. The relationship between the number of Wolf Sunspot and the anomalies of sea surface temperature was very closer after the late of 1980s than those before the early of 1980s in Korean waters.

• 한국환경보건학회지
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• 제22권1호
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• pp.1-4
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• 1996

I have conducted two testings to find out which water is better for drinking water. First, I made 20 mM L-DOPA solutions by solving L-DOPA (3,4-Dihydroxyphenylalanine) in tap water, Waters' mineral water and reverse osmotic water. Then I measured activities after adding Tyrosinase (purifide enzyme, step 3), which was extracted from Salanum melongena(mad apple), in each L-DOPA solution. Second, I solved 0.1, 0.5 and 0.9% salt in each 20 mM L-DOPA distilled water to measure activity of each salt solution. The results of the testings are as follows: 1. 10 minutes after adding Salanum melongena(mad apple) tyrosinase in each L-DOPA solution, activity of Waters' mineral water was 0.867 tap water 0.777 and reverse osmotic water 0.742. 2. Activity of Waters' mineral water was higher than that of tap water by 10.4% and higher then reverse osmotic by 14.4%. 3. Activity of Waters' mineral water was much higher than that of 0.9% salt water by 41.8%. 4. The optimum pH of Salanum melongena (mad apple) tyrosinase is 9.0. Most enzymes working in the human metabolism are alkaline and body fluids' pH also alkaline. In conclusion, an alkaline water is believed better than an acidic water for drinking.

• 한국수산과학회지
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• 제23권3호
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• pp.208-214
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• 1990

한국 남해에 있어서 식물플랑크촌의 현존양은 4월이 가장 많으며 그 지리적 분포상태는 주로 연주도와 대마도간의 수온전선형성해역에 가장 풍부하고 그 전선에서 연안측이 외양측보다 더욱 풍부한 경향이므로 전선형석 위치에 따라 그 농도가 달라지게 된다. 현존양이 2월과 4월에는 최고양으로 출현한 205선의 01점에 8월에는 반대로 최소양으로 출현한 이유는 이 해역의 환경요인이 다른 연도의 것보다 뛰어나게 고온, 고염, 빈산소 및 빈영양상태이므로 이들의 특성을 지닌 Tsushima 난류수괴가 연안까지 침투한 까닭인 것으로 사료된다. 출현종류는 33속 72종 중 규조류가 27속 61종이고 경모조류가 6속 11종이며 시기별 출현종류수는 출현량이 4월에 가장 많은데 비해 8월이 가장 많은 것으로 나타났다. 우점종의 조성은 2월은 Eucampia zodiacus, 4월은 Skeletonema costatum과 Chaetoceros curvisetus 및 8월은Chaetoceros affinis 등으로서 시기별로 대차가 있었다. Eucampia zodiacus는 2월과 4월에 있어서 남해연안수역과 제주도 서방의 혼합수역을 지표하는 지표종으로서의 가치가 있다고 본다.

• 수산해양기술연구
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• 제57권3호
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• pp.214-227
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• 2021

The distribution of tidal current and tidal induced residual current, topographical eddies and tidal residual circulation in the waters surrounding the Geumo Island-An Island channel were identified through numerical model experiments and vorticity balance analysis. Tidal current flows southwest at flood and northeast at ebb along the channel. The maximum flow velocity was about 100-150 cm/s in neap and spring tide. During the flood current in the neap tide, clockwise small eddies were formed in the waters west of Sobu Island and southwest of Daebu Island, and a more grown eddy was formed in the southern waters of Geumo Island in the spring tide. A small eddy that existed in the western waters of Chosam Island during the ebb in neap tide appeared to be a more grown topographical eddy in the northeastern waters of Chosam Island in spring tide. Tidal ellipses were generally reciprocating and were almost straight in the channel. These topographical eddies are made of vorticity caused by coastal friction when tidal flow passes through the channel. They gradually grow in size as they are transported and accumulated at the end of the channel. When the current becomes stronger, the topographic eddies move, settle, spread to the outer sea and grow as a counterclockwise or clockwise tidal residual circulation depending on the surrounding terrain. In the waters surrounding the channel, there were counterclockwise small tidal residual circulations in the central part of the channel, clockwise from the northeast end of the channel to northwest inner bay of An Island, and clockwise and counterclockwise between Daebu Island and An Island. The circulation flow rate was up to 20-30 cm/s. In the future, it is necessary to conduct an experimental study to understand the growth process of the tidal residual circulation in more detail due to the convergence and divergence of seawater around the channel.

• Animal Systematics, Evolution and Diversity
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• 제9권2호
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• pp.91-102
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• 1993

한국근해의 10개의 지역에서 채집된 동정한 결과 Oithona속의 18종이 밝혀졌으며, 이들 중에 대한 검색표를 작성하였다. 그 중 다음의 9종을 미기록종으로 보고한다. Oithona atlantica, O. attenuata, O. davisae, O. hamata, O. longisphina , O. oculata, O. simplex, O. tenuis, O. vivida.

• 한국수산과학회지
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• 제16권4호
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• pp.401-409
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• 1983

1981년과 1982년 $4{\sim}6$월에 한국 남해와 서해 연근해에서 채집된 멸치의 난치어 및 해양관측 자료를 사용하여 수괴배치에 따른 멸치의 난치어의 분포를 분석하였다. 온도전선은 남해에서는 제주도와 대마도를 잇는 선상에서 한국남안연안수와 대마난류간에 형성되었고 서해에서는 태안반도이남해역과 해안선과 평행하게 남북으로 한국서안연안수와 황해냉수간에 형성되었다. 한국남해에서 멸치난은 온도전선 내측인 연안측에서, 멸치 치어는 온도전선을 중심으로 연안측과 외해측으로 분리되어 출현하였다. 그러나 한국서해에서 멸치난과 치어는 온도전선내측과 온도전선역인 $12^{\circ}C$ 이상의 해역에서만 출현하였다. 치어의 체장조성을 보면 남해에서는 연안측에서 전기자어가, 외해측에서 후기자어 및 치어기의 멸치가 주로 출현하였으나, 서해에서는 남부해역에서는 전기자어가 북부해역에서는 후기자어가 주로 출현하였다. 또한 온도전선의 경도가 큰 1981년에는 1982년에 비하여 난과 치어의 분포범위가 크게 제한을 받으므로서 전선의 강약은 난과 치어의 분포에 큰 영향을 주는 것으로 추정된다.

• Animal Systematics, Evolution and Diversity
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• 제24권1호
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• pp.129-133
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• 2008

A pagurid crab carrying half of a bivalve shell was collected from Jejudo Island and identified as Porcellanopagurus nihonkaiensis. A diagnosis with illustrations of this specimen is presented. Although, Komai and Takeda (2006) reported this species as rare and known only from Japan, its range is now extended to Korean waters. At present, it is the only species of the genus Porcellanopagurus represented in Korean waters.