• Journal of fish pathology
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• v.4 no.1
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• pp.23-30
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• 1991

This paper deals with the distribution of coliform group bacteria and the environmental factors in Suyeong Bay from November 1990 to February 1991. The ranges of environmental factors were as follows : Salinity 16.84~34.93%, Dissolved Oxygen $0.58{\sim}6.79m{\ell}/{\ell}$, COD 0.48~5.06 ppm, Nitrite $0.42{\sim}18.82{\mu}g-at/{\ell}$, Nitrate $0.50{\sim}53.23{\mu}g-at/{\ell}$, Ammonia $3.73{\sim}56.16{\mu}g-at/{\ell}$, Silicate $5.18{\sim}147.29{\mu}g-at/{\ell}$. The coliform group and fecal coliform group ranged $1.1{\times}10^2{\sim}2.4{\times}10^5/100m{\ell}$, $1.7{\times}10{\sim}3.5{\times}10^4/100m{\ell}$ each other. The ratio of TC/FC was 1.73~58.49 during study periods. Among the composition of coliform group, E. coli was dominent(64.4%), which was appeared all studying stations. E. coli I type was accounted for 97.4% in the E. coli.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.4
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• pp.259-268
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• 2005

There has been a growing interest in the elimination of anoxic layer in the Youngsan River Estuarybecause the anoxic water mass caused mainly by the inflow of fresh water from the sea wall might cause the mass reduction of benthos during summer. An ocean outfall system to discharge treated wastewater into sea water may be used as one of the effective and economical ways to eliminate the anoxic layer. The suitable ocean outfall design is generally proposed for the prediction of the buoyant jet behavior in the near field. The parameters including CTD and current data are taken into account f3r more reliable buoyant jet behavior calculation. One of the numerical models, CORMIX 1, approved by EPA is used herein for the prediction of the trajectorial variation of the cross-sectional salinity and DO concentration distribution on the calculated buoyant jet boundary according to the tidal periods. On the basis of the results, it is suggested that the single port outfall is a useful system to eliminate the anoxic layer. Proper strategies are also proposed for achieving desirable ambient conditions.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.5
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• pp.474-483
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• 2015

In order to understand the seasonal change of phytoplankton as well as the effect of water physico-chemical parameters, we investigated 18 stations in coastal areas of the East Sea in February, May, August and November in 2009. The taxa of phytoplankton observed in this study were classified as 37 Bacillariophyceae, 22 Dinophyceae, 1 Euglenophyceae, 3 Dictyophyceae and 1 Cryptophyceae. Phytoplankton abundance ranged from $1.2{\times}10^3cells/L$ to $246.6{\times}10^3cells/L$(with a mean value of $24.8{\times}10^3cells/L$), the highest biomass was observed in May. The dominant species were Leptocylindrus danicus, Chaetoceros affinis, Pseudo-nitzschia pungens, Thalassionema nitzschioides and etc. Pearson's correlation co-efficient between phytoplankton abundance and other water parameters showed the positive relationships with pH, DO, Secchi-disk depth, and SS, the negative relationships with $SiO_2-Si$. Seasonal patterns of phytoplankton dominant species were affected by the characteristics of water masses based on T-S diagram analysis. In particular, phytoplankton distributional patterns were related with water temperature in May and salinity in August, respectively. According to the result of MDS(Multi-dimensional scaling) using the phytoplankton abundance and species composition, the spatial distribution of phytoplankton were characterized with Ganwon(Group A) and Gyeongbuk(Group B) at the coastal areas of Jukbyeon or Uljin.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.1
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• pp.13-23
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• 2008

In coastal region, eutrophication, Do deficit and red tide are frequently occurred by influx of fresh water. When the fresh water containing pollutants is discharged into the sea, the surrounding water is contaminated by dispersion of freshwater flowing into coastal waters. The prediction and analysis about the dispersion process of the discharged fresh water should be conducted. A modeling system using GUI was developed to simulate hydrodynamic flow and fresh water dispersion in coastal waters and to analyze the results efficiently. The modeling module of the system includes a tide model using a finite element method and a fresh water dispersion model using a particle-tracking method. This system was applied to predict the tidal currents and fresh water dispersion in Mokpo coastal zone. To verify accuracy of the hydrodynamic model, the simulation results were compared with observed sea level and time variations of tidal currents showing a good agreement. The fresh water dispersion was verified with observed salinity distribution. The dispersion model also was verified with analytic solutions with advection-diffusion problems in 1-dimensional and 2-dimensional simple domain. The system is operated on GUI environment, to ease the model handling such as inputting data and displaying results. Therefore, anyone can use the system conveniently and observe easily and accurately the simulation results by using graphic functions included in the system. This system can be used widely to decrease the environmental disaster induced by inflow of fresh water into coastal waters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.383-386
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• 2005

CCW(China Coastal Water) is different each year. It appears clearly from June to October in the neighboring sea of Jeju island. It appears in June, and it's strong most in August, after tat disappears in October. CCW appeared clearly at 1996 and 1999 during investigation period(1995 to 1999). SLA and SST appear annual variations(about 365day), semi-annual variations(about 180day) from power spectral density. After PCA(Principal component analysis), it's different. PCA of SLA shows 43day variations and PCA of SST shows 259day variations. SLA and SST appear annual variation, semi-annual variation and seasonal variation from power spectral density. SLA appeared that summer and fall of 1996 and 1999 is higher than other years. It seem to be being the relationship which is close with the severe rain strom. Temperature distribution of sea surface according to season is different, but clearly water temperature boundary divides this area into Yellow Sea and East China Sea. It considered that CCW follow according to boundary of temperature. The variation which it follows at time of SLA and SST is faster about one month to three month at Yangtz.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.151-163
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• 2003

In this study, we investigated the physiochemical characteristics of temporal estuarine environment formed during the summer flood season (consecutive rainy days with average 50 mm day$^{-1}$ precipitation) in the coastal area of South Sea of Korea. The freshwater from the Seomjin River was characterized by lower temperature, salinity and pH, and high concentrations of COD and nutrients. In the summer flood season, such peculiar Somejin-River freshwater was dispersed southward along the coast of Yeosubando-Dolsando-Geumodo, form-ing temporal estuarine environment (defined as "Coastal Pseudo-Estuary" in this study) throughout the entire study area (as far as 60 km from the Seomjin River mouth). Compared to the winter dry season, the DIN/DIP ratio was almost doubled (16-36) during the summer flood season. This excessive nitrate supply during the summer flood season was probably due to nitrogenous fertilizer. Distribution and behaviors of physiochemical factors in this coastal pseudo-estuarine environment were controlled not only by the runoff of the Seomjun River (physical mixing of river water with seawater) but also by the biogeochemical estuarine processes which are mostly similar to those of the river estuary.r estuary.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.3
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• pp.112-124
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• 2016

In order to see the spatio-temporal distribution patterns of macrobenthic fauna in subtidal areas of Nakdong River estuary, benthic fauna samples were collected seasonally at 8 sites in subtidal areas of Nakdong River estuary from February, 2013 to November, 2015. Sandy sediment facies was found in the southern part of the barrier islands in Nakdong River estuary while muddy sediment facies occupied at sites in offshore areas. The bottom salinity of the study area was measured greater than 30 psu during the study period. The mean species richness and density were estimated as 266 species and $859ind\;m^{-2}$, respectively. Polychaete worms were the most abundant fauna group, and four polychaete species such as Goniada maculata, Sternaspis chinensis, Magelona japonica, and Heteromastus filiformis occurred as dominant species in this study area. Pseudopolydora kempi known as an opportunistic species occurred dominantly only in August, 2013. From the multivariate analyses, the macrobenthic fauna in the subtidal area of the Nakdong River estuary could be divided into 2 assemblages that each occupied sites near barrier islands and offshore areas by sediment facies.

• Food Science and Preservation
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• v.25 no.1
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• pp.19-26
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• 2018

In this study, we aimed to increase the utilization of non-commercializable peach fruits collected during harvesting and distribution and to promote the transition of a high value-added industry. After producing pastes from the flesh of different peach varieties, we used these pastes as ingredients in the production of Kochujang. We then performed a comparative analysis on the quality characteristics of the peach-added Kochujang and commercially available Kochujang products. Peach-added Kochujang exhibited a lower pH and reduced sugar, salinity, reducing sugar, ash, and calorie content than those of commercially available Kochujang products. However, the Kochujang had slightly higher pH and moisture content than commercially available products due to high organic acid and moisture contents of peach flesh. In terms of content of inorganic elements, commercial Kochujang products exhibited higher sodium and magnesium content, whereas peach-added Kochujang had higher potassium content. In particular, the lower sodium and higher potassium content of peach-added Kochujang indicates that this product could be used as a functional food to prevent various diseases caused by excessive sodium intake among Koreans. After comparing the products in terms of phenol and flavonoid content, we concluded that ethanol extracts of peach-added Kochujang showed higher phenol content than those of the commercially available Kochujang products. In contrast, the distilled water extracts of peach Kochujang showed higher DPPH free radical scavenging activity than that of commercially available Kochujang products.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.224-232
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• 2019

This study evaluated the physicochemical and microbial quality characteristic of seasonal commercial kimchi for hygienic safety levels. The pH of seasonal commercial kimchi was 3.84-6.36 and the titratable acidity and salinity of the samples were 0.21-1.16 and 1.19-1.54%, respectively. The content of nitrate and nitrite in the commercial kimchi were lower in the spring and summer, which was affected by acidic condition of the kimchi depending on fermentation. Heavy metal contents in commercial kimchi are not an issue because they were detected only at very low levels. The total aerobic bacteria and coliforms counts ranged from 5.25 to 8.44 Log CFU/g and 0.00 to 5.08 Log CFU/g, respectively. The total aerobic bacteria and coliforms were detected more in summer than in the other seasons. E. coli was detected in three of the samples tested. Food-borne pathogens were not detected in any of the samples except for B. cereus. B. cereus was detected in the fall in more than 70% of samples. These results suggest that commercial kimchi distributed in the fall maintain the quality properties and the microbiological safety of kimchi compared to the other seasons. Therefore, further studies as an effective distribution system for the particular seasons will be needed to guarantee the hygienic safety levels of commercial kimchi required by the consumers.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.340-354
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• 2021

The aim of this study was to investigate the spatial and temporal distribution of phytoplankton biomass and community composition in Jinhae Bay on the southern coast of Korea. Phytoplankton pigment analysis was conducted using ultra performance liquid chromatography (UPLC) were conducted from April to December 2019 at seven stations. Temperature, salinity, and dissolved oxygen (DO) and inorganic nutrients (dissolved nitrogen, dissolved phosphorus, and orthosilicic acid) were measured to investigate the environmental factors associated with the structure of phytoplankton community. Phytoplankton biomass (Chl-a) was the highest in July (mean 15.4±4.3 ㎍/L) and the lowest in December (mean 3.5±0.6 ㎍/L). Fucoxanthin was the most abundant carotenoid and showed a similar variation pattern to Chl-a, peridinin, and Chl-b. Phytoplankton community composition analysis showed that diatoms were a predominant group with an average abundance of 70 % whereas chlorophytes, cryptophytes, and dinoflagellates often appeared with lower averages. Further, the dominance of diatoms was closely correlated with water temperature and N:P ratio, which might be influenced by high temperatures in the summer and nutrient loading from the land. Additionally, freshwater and nutrient input by rainfall was estimated to be the most important environmental factor. Hence, the spatial and temporal variations in the composition of phytoplankton pigments and phytoplankton community were correlated with physicochemical and environmental parameters.