• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.2
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• pp.186-191
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• 2024

In this study, we analyzed the nutritional compositions of five species of flounder inhabiting Korean coastal waters. In terms of proximate composition, the moisture and crude fat contents of flounders ranged from 75.16±0.37 to 79.94±0.09 g/100 g and 0.48±0.02 to 4.07±0.09 g/100 g, respectively, and showed a negative correlation. Crude protein contents among the five species were found to range from 18.74±0.37 to 19.69±0.44 g/100 g and showed no significant inter-species differences. Among these flounders, Clidoderma asperrimum was characterized by the highest crude fat and total fatty acid contents of 4.07±0.09 g/100 g and 2,739.39 mg/100 g, respectively, as well as the highest content of polyunsaturated fatty acids, including EPA and DHA, at 620.24 mg/100 g. Hippoglossoides dubius was found to have a total amino acid content of 18,971.36 mg/100 g. Our finding in this study regarding the nutritional profiles of flounders will provide valuable information for industrial use.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.188-192
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• 2024

This is the first report of Apogon erythrinus (Perciformes: Apogonidae) from Korea. A single specimen (33.6 mm SL) was collected by a fish pot from the coastal waters of Jeju-do Island on 28 October 2009. This species is characterized by having 5~6 predorsal scales, 7~9 developed gill rackers, end of second dorsal fin spine not reaching the middle of second dorsal fin base when depressed, and posterior margin of body scales reddish-brown. To confirm the correctness of species identification, the DNA cytochrome c oxidase subunit I sequence was obtained from the sample and compared with those of cardinalfish species recorded in the NCBI database. As a result, it was well-matched to A. erythrinus. We newly added this species to the Korean fish fauna and proposed a new Korean name, "Kueun-nun-eol-ge-bi-neul" because the eyes are large compared to its body.

• Journal of the Korean GEO-environmental Society
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• v.25 no.4
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• pp.5-12
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• 2024

In the case of creating a site in the reclaimed land (public waters), due to the nature of the coastal sedimentary ground, large-scale construction materials are required, It is necessary to utilize soft clay, which is inevitably generated during construction of the complex, as a fill material in terms of resource recycling and economic aspects (reducing the amount of embankment required). In this study, changes in the consolidation characteristics of cut-out disturbed soft clay due to the recycling of soft clay soil were identified, and a consolidation settlement design plan was proposed. Through the results of the consolidation test of the study site, the change in consolidation characteristics (compression index reduction, precede load uncountable) due to disturbance (cutting) was confirmed, the method of calculating (consolidation settlement) the filling clay layer as the composite target layer (consolidation target layer, loading load layer) was analyzed as a result consistent with the actual behavior.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.372-377
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• 2023

This is the first report of Trachinotus blochii (Perciformes: Carangidae) from Korea. Single specimen (89.8 mm SL) was collected by seine fishing from the coastal waters of Busan on 13 September, 2023 and two specimens (29.53~30.78 mm SL) were collected by scoop net from Jejudo Island, Korea. This species is distinguishable from the most similar species, Trachinotus blochii as follows: it has the no black spots (vs. black spots in T. baillonii), 21~25 dorsal fin rays (vs. 18~20), and 20~24 anal fin rays (vs. 16~18). In order to confirm their taxonomic status, their mitochondrial DNA cytochrome c oxidase subunit I sequences were obtained and compared with those of carangid species recorded in the NCBI database. As a result, it was perfectly matched to T. blochii, and differed from T. baillonii (genetic distance=5.46%). We propose a Korean name, "Mu-jeom-mae-ga-ri", for the species.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.378-383
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• 2023

A re-examination of Luciogobius guttatus was conducted using 84 samples, which lives on all coastal waters of Korea. As a result, 41 specimens (31.3~54.4 mm SL) collected from the west and south coasts were classified as L. martellii. The morphological features of L. martellii as follows: number of abdominal vertebrae 16; total number of vertebrae 35~37; dorsal fin base length longer than upper caudal peduncle length or equal; one free ray on its upper pectoral fin; and edge of tail fin white. Among these, the most prominent morphological difference in L. guttatus is comparing the dorsal fin base length and upper caudal peduncle length, which is also well observed in syntypes of L. martellii. We proposed a new Korean name, "Geom-jeong-mi-kken-mang-duk" referring to their color.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.3
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• pp.124-132
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• 2010

In spite of the global importance of primary production of phytoplankton, some primary production data in Korean coastal waters still need to be better processed. The daily rates of water column primary production is generally estimated by integrating the primary production per unit volume over time and depth, but efforts for time integration algorithm have been conducted insufficiently. In this study a mathematical equation evaluating daily primary production integrated over time of a day is proposed and the effectiveness of the model is tested on Saemangeum Lake. The daily primary productions computed with the proposed equation were nearly the same with the results numerically integrated by substituting solar irradiance data. It was suggested that better estimation of primary production would be obtained by using monthly or weekly means of solar irradiance rather than more variable daily data. Because of the vertically heterogenous distribution of phytoplankton, it's hard to integrate the equation over depth to give the daily rates of primary production per unit area of water surface. However, the problem would be solved if, after the vertical distribution of phytoplankton was classified into several patterns and reduced to mathematical formula, every composite function of time integrated equation and chlorophyll distribution equation was integrated successfully.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.1
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• pp.35-42
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• 2007

Thermal discharges from the nuclear power plants into neighboring Korean coastal waters have raised serious disputable arguments from the two parties of local fishermen and scientists involved since late 1970's. To meet the social demands and provide scientific and reasonable solutions, new set of standards have been established which will guide through measuring and processing the various variables and parameters in environmental and fishery impact assessment procedures for the thermal discharge from the nuclear power plants. These are made possible for the first time by the combined efforts by Korean Oceanography Society and Fishery Society. In this paper, Thermal Disharge Impact Index(TI) is proposed by the probability of the local temperatures exceeding critically to local fishery multiplied by the weighted sum of diverse environmental and ecological factors. The TI is essentially conceived to overcome the long-exising bad practices based on the particular excess temperature such as 1. The proposed TI based on the guideline principle proposed by the UNEP(2002) is expected to be practical, economic and self-adaptive. To prove the usefulness of the TI, it is highly recommended to conduct prototype experiments and exercises in a particular nuclear power plant site in the near future.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.11-20
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• 2018

In planktonic ecosystems, the microplastics are considered as a potential food source for the zooplankton. To study a relationship between the zooplankton and the neustonic microplastics, a research experiment was carried out during May in the surface layers of the Yeosu coastal areas including Yeoja Bay, Gamak Bay, Yeosuhae Bay, and Botdol Sea. A neustonic zooplankton net (mesh size $300{\mu}m$; mouth area $30cm{\times}18cm$) was towed from the side of the ship in the event that it would not be affected by waves crashing by the ship at a speed of ca. 2.5 knots. All of the microplastic particles were separated from the zooplankton. The zooplankton and microplastics were appearing in a range of 61 to $763indiv.m^{-3}$ and 0.0047 to $0.3471particle\;m^{-2}$, respectively. It was noted that the Acartia omorii, Paracalanus parvus s. l., Labidocera euchaeta, A. hongi, decapod larvae, and cirriped larvae were predominantly seen in the experiment. For verifying relationships between zooplankton and environmental factors in addition to microplastics, a model redundancy analysis (RDA) was performed. The zooplankton were divided into two groups on the basis of feeding types (i.e. particle feeders, and carnivores), and the associated zooplankton larvae were also separately considered. A review of the additional environmental factors such as water temperature, salinity, turbidity, chlorophyll-${\alpha}$ concentration, diatom density, and dinoflagellate density were also contained in the analysis. The results showed that a noted zooplankton abundance had no close relation with the occurring number of microplastic particles, but rather was significantly related with other noted environmental factors such as temperature, salinity, turbidity, and chlorophyll-${\alpha}$ concentration. This fact implies that most zooplankton can feed themselves as a unit, by selecting the most likely available nutritious foods, rather than microplastics under the circumstance of food-richness areas, such what food resources are available as in the location of coastal waters.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.8-34
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• 2014

We reviewed foreign evaluation systems based on the macrobenthic and macroalgal communities and developed a system, composed of a set of ecological indices able to evaluate the functionality (FI, Functional Index; estimation of stability and productivity) and maturity (MI, Maturity Index; comparisons with biological parameters of natural reefs) of artificial reefs by comparing the status in the adjacent natural reefs in Korean coastal waters. The evaluation system was applied to natural and artificial reefs/reef-planned areas (natural reefs), established in the 5 marine ranching areas (Bangnyeong-Daechung, Yeonpyung, Taean, Seocheon and Buan) in the west coast of Korea. The FI ranged between 31.6 (Bangnyeong-Daechung) and 72.5% (Buan) and MI did between 53.1 (Seocheon) and 76.9% (Taean) in average. The evaluation of artificial reefs by the two indices, showed the most appropriate status in Taean. The FI between the adjacent artificial and natural reefs were in significant linear relationship ($r^2=0.83$, p=0.01). This indicated the local status of biological community may be critical in determining the functionality of the artificial reefs. We have suggested an integrative but preliminary evaluation system of artificial reefs in this study. The output from the evaluation system may be utilized as a tool for environment/resource managers or policy makers, responsible for effective use of funds and decision making. Given the importance, we need to use the options to enhance and improve the accuracy as follows: (1) continuous validation of the evaluation system and rescaling the criteria of indicators, (2) vigorous utilization of observation and experience through the application and data accumulation and (3) development and testing of brand-new indicators.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.79-91
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• 2005

In order to understand growth characteristics of ten major species of microalgae responsible for frequent harmful algal blooms in Korean coastal waters, the growth rates of the isolates were examined in relation with the impacts of water temperature, salinity and irradiance. In addition, their bloom events since 1990 as well as monthly abundance of vegetative cells were analyzed. Heterocapsa triquetra, Eutreptiella gymnastica and Alexandrium tamarense were considered as relatively mid temperature adapted species in that growth rates were comparatively high at low water temperatures of $10{\sim}16^{\circ}C$ and drastically decreased at above $22^{\circ}C$. Prorocentrum micans and Pyramimonas sp. were categorized as relatively high temperature adapted species by showing comparatively better growths at high water temperatures above $25^{\circ}C$. Akashiwo sanguinea, Heterosigma akashiwo, Prorocentrum minimum and Scrippsiella trochoidea were eurythermal species with relative high growth rates in a broad ranges of water temperature, $16{\sim}25^{\circ}C$ were slightly halophobic, showing better growths at low salinities of $10{\sim}30$ psu than at above 35 psu. H. akashiwo, P. minimum and H. triquetra were euryhaline species with remarkable growths in a broad ranges of salinity, 15-40 psu. Frequent algal blooms by these three species at extremely low salinities below 25 psu after rainfall were attributed to their euryhaline and slightly halophobic physiological characteristics. Growth rates of H. akashiwo, P. minimum and Pyraminonas sp. increased with the increase of irradiance within the experimental ranges of $2{\sim}150\;{\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$. However, A. sanguinea, A. tamarense and H. triquetra showed better growths at comparatively low irradiance of $50{\sim}100\;{\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$ and drastic decreases in growth rates above $150\;{\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$ of irradiance. Overall, relatively high temperature adapted species make blooms frequently in high water temperature season with strong natural irradiance, and relatively low temperature adapted species grow better at low water temperature with relatively weak natural irradiance.