• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.495-499
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• 2003

Age and growth of purpulish Washington clam (Saxidomus purpuratus) was investigated from 480 samples monthly collected from January to December 2002 in Jinhae Bay, Korea. Examination of outer margins of the shell revealed that the translucent zone was formed once a year from March to April, it can be used as annulus. Ages were determined from ring radius of shell, and maximum age of the the clam was 9 years. The spawning period was from May to October, and the main spawning occurred in July. The relationship between shell length (SL) and shell height (SH) was $SH=0.8405{\times}SL^{-4.9709}\;(R^2=0.97)$ and that between the shell length (SL) and total weight (TW) was $TW=0.9580{\times}10-4{\times}SL^{3.220}(R^2=0.97).$ The von Bertalanffy growth equation were $SL_t=125.57(1-e^{-0.2523(t+0.5367)},\;TW_t=549.26(1-e^{-0.2523(t+0.5367)})^{3.220}.$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.500-508
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• 2003

The fauna associated with mussel (Mytilus galloprovincialis) beds and vertical distribution of macrobenthos were studied on the Goijeong rocky shore in Jinhae Bay, Korea. Sampling was conducted seasonally using a quadrate from January to October, 1998. In the first experiment, to reveal the community structure of macrobenthos in mussel bed, a total of 62 species $(10,690ind./m^2,\;3,802.1\;g/m^2)$ were identified, which included polychaetes $(32\;spp.,\;52.6\%),$ molluscs (16 spp.), crustaceans (10 spp.), and others. The density-dominant species were Pseudopolydora antennata, Nereis heterocirrata, Littorina brevicula and Balanus kondakovi. And the density of associated fauna was correlated with that of mussel (r=0.951, p=0.049). In the second experiment, to reveal the vertical distribution of macrobenthos on the rocky shore, ANOVA showed highly significant differences between the density of top 5 dominant species (Chthamalus challengeri, Littorina brevicula, Balanus kondakovi, Septifer virgatus and Granulilittorina exigua) and tidal levels (P=0.000). Vertical distribution of macrobnethos was characterized by Ghthamalus belt and Balanus-Septifer belt in the mussel bed.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.141-150
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• 2016

Most previous studies on dinoflagellates in Korean coastal areas were conducted without morphological descriptions and illustrations of the observed dinoflagellates. This indicates that the species and diversity of dinoflagellates may have been respectively misidentified and underestimated in the past, probably due to cell shrinkage, distortion and loss caused by sample fixation. This study provides information on the morphological observations of four dinoflagellate orders (Prorocentrales, Dinophysiales, Gonyaulacales and Gymnodiniales) from Jangmok Harbour in Jinhae Bay, Korea. The unfixed samples were collected weekly from December 2013 to February 2015. A total of 13 genera and 30 species were identified using light and scanning electron microscopy, although some samples were not clarified at the species level. Harmful dinoflagellates, Prorocentrum donghaiense, Tripos furca, Alexandrium affine, A. fundyense, Akashiwo sanguinea and Cochlodinium polykrikoides, were identified based on the morphological observations. The results also reflect the occurrence and identification of dinoflagellates that had not been previously recorded in Jangmok Harbour.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.1
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• pp.27-36
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• 1998

A three-dimensional numerical model of water circulation has been developed. The model employs the equations on $\sigma$-coordinate and the finite element method for numerical integration. To verify accuracy of the model, a series of numerical experiments have been conducted. The experiments include wind-driven currents in an one-dimensional channel, wind-driven currents in a square lake, and tidal current distributions in Masan-Jinhae Bay. The simulation results showed good agreements with the analytic solutions for wind-driven current and the field data sets in Masan-Jinhae Bay. The model can be used widely for modeling of water circulation in the waters with a complex geometry.

• The Korean Journal of Malacology
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• v.28 no.3
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• pp.269-274
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• 2012

The genetic variation of Ark Shell, Scapharca broughtonii black was estimated using six polymorphic microsatellite (MS) loci in 443 individuals collected from five populations in Korea. The mean numbers of alleles per locus in five populations were 10-28. The mean number of alleles per locus in Jinhae Hatchery (JHH) population showed the least value as 15.5, but that in Gangjin (GJ) population showed the most value as 20.3. The mean expected heterozygosity in Saryangdo (SR) population showed the least value as 0.817, but that in Gangjin (GJ) population showed the most value as 0.831. In Jinhae hatchery(JHH) population, the mean expected heterozygosity was 0.822, there was no significant difference from those of wild population. The $F_{ST}$ values in Gangjin (GJ) population showed significant difference from those of the other populations, which revealed Gangjin (GJ) population is genetically different from the other populations. The $F_{ST}$ values among Jinhae Hatchery (JHH) population, Jinhae (JH) population and Saryangdo (SR) population showed lower values than the others, which implies there was a gene flow among these three populations. The $F_{ST}$ value and genetic distance between Jinhae (JH) population and Saryangdo (SR) population showed the least value as 0.0001 and 0.0386, indicating that these two populations were genetically the same.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.140-149
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• 2018

Seasonal variations in the community structure of larval fish assemblage in Jinhae Bay were investigated in February, May, August and November of 2015, and in the same months in 2016. During the study period, a total of 28 larvae species belonging to 24 families were collected. The dominant species were Clupea pallasii, Liparis tanakae, Callionymidae sp., Sillago japonica, Ernogrammus hexagrammus and Engraulis japonica. These six species accounted for 77.6% of the total number of larvae during the survey period. The larvae of C. pallasii and L. tanakae were exclusively caught in February 2015 and 2016, while those of Apogon lineatus and Sillago japonica were exclusively caught in August 2015 and 2016. Overall, species diversity of the fish larvae was highest in February and August, although it was relatively low in May. The results of the non-metric multidimensional scaling (nMDS) analysis using the number of individual larval fish showed that they are divided into four seasonal groups. Our results showed that the community of larval fish in Jinhae Bay was affected by seasonal changes in temperature and the emergence of spawning fish species. Additionally, we suggest that the high abundance of larval fish came from around Jam-do and the northern part of Chilcheon-do; these locations are the main spawning grounds of Jinhae Bay.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.627-639
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• 2014

In respect of the nutrients cycling in coastal environment, regeneration in bottom layer is one of major source of nutrients. We analyzed the bottom water quality at the 14 stations during 9 years from 2004 to 2012 to investigate the characteristics of nutrients at bottom layer in Jinhae Bay. Concentrations of DIN, DIP and DSi showed the large seasonal variation and were higher in summer. Especially, average concentrations of these nutrients were two times higher in hypoxic season than in normoxic season. In summer, high concentrations of DIN, DIP and DSi caused by regeneration were common feature, but spatial distribution of DSi differ from that of DIN and DIP. DIN and DIP were higher in Masan Bay, while DSi was higher in Masan Bay as well as in center of Jinhae Bay. In comparison with DIN and DIP, DSi was significantly affected by nutrients regeneration at bottom layer in whole season. According to time series analysis, DIN concentration was decreased from approximately $14{\mu}M$ to $6{\mu}M$. This result induce that Si:N ratio at bottom layer in Jinhae Bay changed from approximately 1 to 3.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.4
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• pp.474-482
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• 2021

An average of two to three typhoons that occur in the Philippines or Taiwan pass through Korea each year owing to the influence of the geographical location and western winds. Because Jinhae Bay is known as Korea's representative typhoon refuge, it is filled with ships during typhoons and later becomes saturated with ships anchored to the surrounding routes. If a strong wind drags an anchored ship, a collision accident may occur because of the short distance between the ships. Therefore, a systematic anchoring safety management of Jinhae Bay is required. In this study, the minimum wind speeds of a dragging anchor based on the water depths of Jinhae Bay anchorages were investigated. When 7-9 shackles were given, the minimum wind speeds were 48-63, 46-61, and 39-54 knots at depths of 20, 35, and 50 m, respectively. As the water depth increased, the length of the cable laid on the sea bed became shorter than 5 m owing to the external force, and the minimum wind speed showed a significant difference of 4-8 knots. In addition, ships with high holding power anchors (AC-14 type) had higher minimum wind speeds than ships with conventional anchors (ASS type). Finally, it was confirmed that at a depth of 50 m, dragging easily occurred even when a high holding power anchor was applied.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.308-323
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• 2021

In this study, we aimed to evaluate the environmental changes in Jinhae Bay caused by cooling water using numerical modeling. Cooling water discharge volume from the results of Case 1 (10 m³ sec^-1) showed that the environmental changes in Jinhae Bay were extremely insignificant throughout the study period. In the simulation conditions of Case 2 (100 m³ sec^-1), there was a decrease in water temperature of approximately 1 - 3℃ within a 5 km radius from the discharge outlet. In Case 3 (1000 m³ sec^-1), a decrease in water temperature of up to 4 - 5℃ was observed within a radius of 8 km from the discharge outlet and cooling water discharge spread throughout the Bay. Growth rate of microalgae decreased by up to 15 % in November, whereas it increased by up to 6 % near the Hangam Bay in Case 3. From the above results, we confirmed that the environmental changes in Jinhae Bay due to cooling water discharged from Tongyeong LNG station are extremely insignificant. Moreover, it is expected that cooling water discharge could be utilized as a counter measure for 'red tide bloom' or 'macroalgae growth'.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.4
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• pp.291-298
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• 2024

As an important fishing ground in the southern coast of Korea, Jinhae Bay is characterized by a high level of fisheries production. However, its marine-ecosystem has shifted owing to environmental changes such as industrial development and high water temperatures over the decades. This study analyzes the fisheries production, discards, mean trophic level, and fishing-in-balance index using annual fishing data from five regions surrounding Jinhae Bay for the period 2005-2022, as well as using additional forecasting trends by 2027 using ARIMA (Auto Regressive Intergrated Moving Average). The results shows, that the production in Goseong will decrease continuously by 2027, as compared with that in other areas. Additionally, byproduct management is considered necessary in Tongyeong. For the marine-ecosystem index, Tongyeong indicates stable catch ratio of large fish species and a fishing-in-balance exceeding 0. Finally, the annual catch variation for six pelagic fish species in Jinhae Bay by 2060 is estimated based on the IPCC climate-change scenario, in which the recent low level that decreased to approximately 20 thousand ton in early 2020 is projected to recover to approximately 40 thousand ton in the 2020s and 2040s, followed by an incremental decline by 2060.