• Journal of Aquaculture
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• v.21 no.3
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• pp.157-166
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• 2008

Species composition and standing crop of phytoplankton were investigated in the ark shell Scapharca broughtonii farming areas from March, 2006 to February, 2007 in Jinhae Bay. Water temperature ranged from 7.56 to $25.90^{\circ}C$, salinity from 13.74 to 34.78 psu, dissolved oxygen from 4.13 to 13.20 mg/L, chlorophyll $\alpha$ from 2.77 to 104.98 $mg/m^2$ and pH from 7.83 to 8.65. Dominant species was Nitzschia and Rhizosolenia from March to May, Skeletonama costatum and Prorocentrum from June to August, Skeletonama costatum, Thalassiosira, Chaetoceros from September to November and Thalassiosira, Chaetoceros from December to February. Colonial diatoms were more dominant than the single cell diatoms. Standing crop was the highest in July at three stations. Standing crop of Skeletonama costatum was the highest as 1,760.0 cells/mL at St. 1, 1,075.2 cells/mL at St. 2 and 698.4 cells/mL at St. 3 in July.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.4
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• pp.205-212
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• 2009

To suggest possible to bioremediation by benthic microalgae Nitzschia sp. isolated from the Jinhae Bay, the studies investigated the effects o flight quality and quantity on the growth of Nitzschia sp. and its growth kinetics for phosphate investigated. The Nitzschia sp. was cultured under blue (450 nm), yellow (590 nm) and red wavelength (650 nm) using light emitting diode (LED) and mixed wavelengths using a fluorescent lamp. The maximum specific growth rate showed the Nitzschia sp. under blue wavelength, although photoinhibition was observed above $100\;{\mu}mol\;m^{-2}\;s^{-1}$. Mixed wavelengths were also observed by decreasing the maximum cell density from high irradiances (>$100\;{\mu}mol$ photons $m^{-2}\;s^{-1}$). The compensation photon flux density ($I_0$) calculated from the mixed wavelengths equated to a depth of 4-10 m in Jinhae Bay, and was lower in the summer season than the depth due to suspended matter (ca. 4 m). Thus, the suitable depth for maximum growth of Nitzschia sp. might be extremely limited. In the growth kinetics for phosphate, half-saturation constant ($K_s$) was similar among different wavelengths, although the maximum growth rate was varied among different wavelengths. Because the $K_s$ was high than that of the phytoplankton, Nitzschia sp. might have adapted to the high nutrient concentrations, and have effective nutrient storage in the cell quota. Thus, Nitzschia sp. may be a useful species for bioremediation of the benthic layer in polluted inner bays by means of irradiated specific wavelength as blue.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.4
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• pp.305-314
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• 2007

We studied spatial and temporal distributions of the phytoplankton and their relationships to physico-chemical environmental factors in the western Jinhae Bay, Korea from November 2003 to August 2004. In most cases, physico-chemical environmental factors showed homogeneous distribution. The phytoplankton communities were composed of mainly diatoms and dinoflagellates, and their standing crops ranged from $16{\times}10^3\;cells\;l^{-1}\;to\;5,845{\times}10^3\;cells\;l^{-1}$ (with a mean value of $555{\times}10^3\;cells\;l^{-1}$). The bloom of phytoplankton was observed in Gohyun Port in the summer. Seasonal variation of phytoplankton standing crops was higher in winter and summer than in spring and autumn. The dominant species were Skeletonema costatum, Akashiwo sanguinea, Pseudo-nitzschia pungens, Dactyliosolen sp., Leptocylindrus danicus, cryptomonads and etc. Especially, S. costatum was predominant in the summer and A. sanguinea (spring and autumn), Pseudo-nitzschia sp. (summer), Guinardia striata (spring), unidentified flagellates (summer) and cryptomonads (spring) appeared to be an opportunistic species. Concentrations of Chl a ranged from $0.6{\mu}g{\cdot}l^{-1}\;to\;16.7{\mu}g{\cdot}l^{-1}$ (with a mean value of $3.4{\mu}g{\cdot}l^{-1}$). The results of the canonical correspondence analysis implies the study area was grouped into the 2 water masses (inner and outer waters of Gohyun Port) and inner waters had higher abundance and Chl a concentration than outer waters. Also, phytoplankton sanding crops were related with temperature, DO and nutrients ($SiO^2$, TN, TP and etc.) in inner waters. Inner water-mass of Gohyun Port expanded between Gacho Is. and Chilchon Is. during the winter.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.101-110
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• 2013

In order to classify the trophic state and environmental quality of marine coastal system, an approach using the characteristics and biochemical composition in the sediments can be available. This research, including 25 coastal bay, belong to 131 stations, was carried out along the south coasts of Korea in February 2007. Type of sediment, total ogranic carbon, total nitrogen, phytopigments and biochemical composition(proteins, lipids, carbohydrates) were analyzed. Result from Multi-dimensional Scaling(MDS) ordination indicates that four group can be identified. The result of ANOVA with tukey test shows that the concentrations of proteins, carbohydrates and biopolymeric carbon were significantly different to four groups. We propose the trophic state classification for these groups using the biochemical composition of sediment organic matter. I group(Masan, Jinhae, Haengam) has been defined as hypertrophic state, II group(Tongyeong, Goseong；Jaran, Geoje et al.), as eutrophic; III group(Gamak, Deungnyang, Yeoja et al.), as mesotrophic and IV group(Sinan, Jindo, Muan), as oligotrophic. On the basis of results reported in this study, the biochemical composition of sediment organic matter could be considered an useful and sensitive tool for the classification of the trophic state of marine coastal systems.

• Journal of Life Science
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• v.12 no.6
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• pp.821-834
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• 2002

In order to measure the inter- and intraspecific genetic divergences within the genus Alexandrium, the variations within the internal transcribed spacer (ITS1 and ITS2) regions and 5.85 ribosomal RNA gene of eight Alexandrium species were examined for 33 strains from diverse geographical locations by direct sequencing. Five isolates of A. tamarense (AT-2, AT-6, AT-10, AT-A and AT-B) from Jinhae Bay, Korea were found to be completely identical to a Japanese strain OFX151-A. The length of the amplified ITSI-5.85-ITS2 region varied from 481 nucleotides (in A. margalefi) to 528 nucleotides (in A. affine CU1-1). ITS1 and ITS2 nucleotide lengths were negatively correlated, whereas a positive correlation was found between their G＋C content. The degree of sequence divergence ranged from 0.3% (1 bp) to a maximum of 53% (305 Up). Pairwise sequence comparisons revealed a small degree of divergence between A. tamarense and A. Pundyense isolates (1.2 - 2.3% ＝ 6-12 bp), but a high degree of divergence between A. tamarense and A. catenella (19.8% ＝ 102 bp), and between A. catenella and A. Pundyense (19.7%). Although most nodes were weakly supported by bootstrap values, some types tend to form independent molecular groups. A. catenella isolates also formed an independent molecular sub-group, with relaticula strong bootstrap values (94% or 85% and 79% or 98%, respectively in PAUP and NJ trees). Interestingly, A. cohorticula and A. frateculus always clustered within the same sub-group, this result being supported by strong bootstrap values. Our results indicate that the ITS regions provide useful informations on hierarchical population genetic structure and a high phylogenetic resolution in intraspecific and interspecific Alexandrium population.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.18 no.1
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• pp.1-10
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• 1982

Diffusion processes in tidal swinging coastal waters are studied by releasing one hundred liters of Rhodamine B four times. Dye patches were formed from instantaneous point sources. The patches were sampled with a pump on a tracking boat, and samples were analyzed with fluorospectro-photometer. The patterns of patches were reconstructed and their characteristics were analyzed in terms of variance of concentration, area estimation, and decrease rate of peak concentration. In all of the four experiments, the dye patches were mos시 elongated to the direction of current axis. the elongation rate was 0.34 on the average. Apparent diffusivities were 620 to 3,000 cm super(2) /sec during initial period of 90 minutes. The variance increased by exp(0.047t) on the average, and peak concentration deceased by exp(-0.044t) on the average.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.297-304
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• 1997

Morphological and Benetic comparision were studied for the arkshell populations of Korea and China. The shell was collected from commercial arkshell bed in Jinhae Bay, Korea and from an hatchery in Young Seong, China. Shell Parameters, number of radial ribs and random amplified polymorphic DNA (RAPD) band were measured. The two populations had morphological and genetic differences. There was significant morphological difference $(P\leq0.05)$ in the ratio of the longest radial rib to the shell length. Posterior parts of the Chinese arkshell were more elongated than those of the Korean arkshell. Number of radial ribs were $36\~41$ for the Korean arkshell and $39\~43$ for the Chinese arkshell. RAPD markers generated tty each of 19 primers were $2\~6$ bands. Genetic diversity between the two Populations was clear since the genetic similarity was very low, not exceeding 0.29. The genetic similarity among the Korean arkshells $(0.58\~0.40)$ was higher than that of the Chinese arkshells $(0.48\~0.32)$.

• The Korean Journal of Malacology
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• v.24 no.1
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• pp.59-66
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• 2008

The ark shell, Scapharca broughtonii were collected from the Jinhae bay in Kyungnam, Korea from April 2006 to October 2007. To assess how much they have tolerance against hypoxia under the compound condition of temperature and salinity, survivorship, oxygen consumption rate and external features of Scapharca broughtonii were measured, The 7 days-$LC_{50}$ of dissolved oxygen (DO) for Scapharca broughtonii at $15^{\circ}C$-ordinary sea water and $26{\pm}1$ psu was 1.98mg/L (confidence limit: 1,45-2.39 mg/L) and 2.63mg/L (confidence limit: 1.76-3.37mg/L) respectively. Whereas 3 days-$LC_{50}$ at $25^{\circ}C$-ordinary sea water was 3.89mg/L (confidence limit: 3.36-4.55 mg/L) and 4 days-$LC_{50}$ at $25^{\circ}C-26{\pm}1$ psu was 3.74mg/L (confidence limit: 3.19-4,43 mg/L). Oxygen consumption rate with each experimental group was decreased during the period exposed to hypoxia. To recovery, they were replaced to ordinary and oxygen consumption rate was increased a little, but all died, The color of the umbo of shell in Scapharca broughtonii was changed dark during hypoxia. These data will provide important fundamental information for examining the causes of mass mortality of shellfish in the summer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.35-41
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• 1988

In order to set up a predictive model for effective spat collection of sea mussel Mytilus edulis , the survival rate and time required at each developmental stage of drifting larvae were surveyed during the period from March 14 to July 20 in 1987 at the Naesan Ri, Jinhae Bay, the southern part of Korea. The advent of D - shape larvae ca. $120\times90um$ um long had three peaks in that area: April 15, May 13 and June 7. Umbo shape larvae ca.$188\times162{\mu}m$ and full grown larvae ca. $289\times280{\mu}m$ long also showed three peaks: April 27. May 24 and June 20 for the former, and May 10, June 5 and June 30 for the latter. Eleven to thirteen days were required for D - shape larvae to develop to umbo - shape larvae. The instantaneous death rate was 0.1300 and the daily survival rate 0.8781 at this intermorphological stage. The turnover time of umbo to full grown larvae varied from ten to thirteen days with a instantaneous death rate of 0.1520, daily survival rate of 0.8590, and mean survival rate of $16.89\%$. Twenty - three to twenty - five days were required for each group of the D - shape larvae to reach a full grown stage, and their mean survival rate was $3.55\%$ during this developmental period.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.432-440
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• 2015

The hydro-acoustic technology has been widely used in not only South Korea but also many foreign countries for various scientific purposes. Unfortunately acoustic data especially collected from field surveys may contain noises caused by a variety of sources. Therefore, it is exceedingly important to eliminate noises when acoustic data are analyzed to derive quantitative results. This study introduced two methods for eliminating noises easily and effectively using post-processing software. Used acoustic data were collected on the Jinhae bay and Tongyeong coast of the South Sea in April 2015. The first method, that is the Wang's method, placed emphasis on 'erosion filter' to eliminate only data samples contaminated by noises. The second method (Yamandu's method) focused on the 'resample by number of pings' to remove pings contained noises. To substantiate the effectiveness of two methods, the mean Sv (Volume backscattering strength), mean height and depth of the fish schools detected were compared between before and after using the noise elimination methods. In the Wang's method the mean Sv was decreased from -52.4 dB to -52.9 dB, and in the Yamandu's method from -52.6 dB to -53.3 dB, indicating that noises were successfully eliminated. The mean height (1.5 m) and depth (19.0 m) were same between before and after using two methods showing that the shapes of fish schools were not changed.