• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.149-157
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• 1998

Seasonal changes of topography, sediment grain size and accumulation rate in the Gomso-Bay tidal flat, west coast of Korea, have been studied in order to understand the seasonal accumulation pattern and preservation potential of the tidal-flat sediments. Seasonal levelings across the tidal flat show that the landward movement of both intertidal sand shoals and cheniers accelerates during the winter and typhoon periods, but it almost stops in summer when mud deposition is instead predominant at the middle and upper tidal flats. Seasonal variations of mean grain size were largest on the upper part of middle tidal flat where summer mud layers were eroded during the winter and typhoon periods. Measurements of accumulation depths from sea floor to basal plate reveal that accumulation rates were seasonally controlled according to the elevation of tidal-flat surface. The upper tidal flat where the accumulation rate of summer was generally higher than that of winter was characterized by a continuous deposition throughout the entire year, whereas in the middle tidal flat, sediment accumulations were concentrated in winter relative to summer and were intermittently eroded by typhoons. The lower tidal flat were deposited mostly in winter and eroded during summer typhoons. Can cores taken across the tidal flat reveal that sand-mud interlayers resulting from such seasonal changes of energy regime are preserved only in the upper part of the deposits and generally replaced by storm layers downcore. Based on above results, it is suggested that the storm deposits by winter storms and typhoons would consist of the major part of the Gomso-Bay sediments.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.265-265
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• 2002

• Proceedings of the Korean Aquaculture Society Conference
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• 2002.08a
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• pp.240.1-240
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• 2002

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.165-174
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• 2016

Feeding behaviour of the manila clam Ruditapes philippinarum was qualitatively and quantitatively characterized by comparing the contents composition in digestive tract of the clam and the phytoplankton community in surface sea water in Gomso Bay, west coast of Korea. The contents of digestive tract comprised diatoms (71.5%), dinoflagellates (13.1%), nannoplankton (6.6%), and detritus including mesozooplankton. The abundance of food organisms in digestive tract of the clam was high in winter and spring, while low in summer and autumn. But The biomass of phytoplankton in surface sea water revealed the highest value in autumn. Also, the larger the clam size increases the abundance of food organisms in digestive tract. The dominant species in digestive tract were Paralia sulcata and Navicula arenaria such as benthic diatoms and dinoflagellate cysts, whereas the dominant species in surface sea water were Chaetoceros, Skeletonema, Asterionellopsis such as pelagic diatoms in genus, cryptomonads, and P. sulcata. Analyses of digestive tract revealed that benthic diatoms especially represent an important constituent of food organisms in the malina clam and different of phytoplankton size and morphology explain preference for food selectivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.587-595
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• 2019

Eighty-three Vibrio parahaemolyticus isolates from surface seawater in Gomso Bay on the west coast of Korea, and commercial fisheries from Gunsan fisheries center were analyzed for the presence of virulence genes and susceptibility to 30 different antimicrobials. All 83 isolates were examined for the presence of two virulence genes (tdh or trh) using polymerase chain reaction; however, neither gene was found in any of the isolates. A disk diffusion susceptibility test, showed that all of the strains studied were resistant to clindamycin, oxacillin, ticarcillin, and vancomycin, and also revealed varying levels of resistance to ampicillin (98.8%), penicillin G (95.2%), streptomycin (20.5%), cefoxitin (14.5%), amikacin (6.0%), cephalothin (4.8%), and erythromycin (3.6%). However, all of the strains were susceptible to 19 other antimicrobial agents, including cefepime, cefotaxime, chloramphenicol, gentamycin, nalidixic acid, sulfamethoxazole/trimethoprim, and trimethoprim. All 83 isolates (100%) were resistant to five or more classes of antimicrobials, and two strains exhibited resistance to ten antimicrobial agents. The average minimum inhibitory concentrations against V. parahaemolyticus of clindamycin, oxacillin, ticarcillin, and vancomycin were 55.9, 98.3, 499.3, and 44.3 ㎍/mL, respectively. These results provide new insight into the necessity for seawater sanitation in Gomso Bay and commercial fisheries, and provide evidence to help reduce the risk of contamination by antimicrobial-resistant bacteria.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.5
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• pp.357-370
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• 2009

EFDC, ESCORT and MIKE21 models are applied at the Gomso Bay to investigate each models' facilities of tidal flat simulation. Comparisons with observation data show that all models simulate hydrodynamic phenomena and tidal flat well. CPU time and WCM are examined to evaluate the efficiency of the models, and the effects of flooding/drying depth and bottom friction are examined to analyze models' facilities of simulating tidal flat. The EFDC model is considered to be fairly good in accuracy, stability and applicability, it is, however, poor in efficiency and its complexity. While the ESCORT model is superior to the EFDC in simulation of tidal flat, it is inferior to the EFDC in CPU time and simulation of bottom friction. The MIKE21 model is excellent in efficiency, but some numerical noise would be detected at low water, not permitting correction of the model.

• 한국해양학회지
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• v.29 no.2
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• pp.183-187
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• 1994

The oxygen and carbon isotopic compositions of the foraminiferal species, Elphidirm dtigoense and Ammonia beccarii tepida, of the tidal flat in the Gomso Bay of the western coast of Korea have been measured. This work was intended to study the relationship between oxygen and carbon isotopic compositions of the foraminifera and present oceanographic environments, and also the difference between two foraminiferal species. The values of $\delta$/SUP 18/O and $\delta$/SUP 13/C of E. dtigoense varied from - 3.20% to + 0.58% and from - 5.26% to - 0.93%, respectively. The values of $\delta$/SUP 18/O and $\delta$/SUP 13/C of A. beccarii tepida varied from - 1.11% to + 0.61% and from - 2.04% to - 1.40%, respectively. Mo significant variations in these values occur from the samples among the upper, middle and lower tidal zones except for the one from the upper tidal zone that has extremely low value. The difference between the two foraminiferal species was 0.20% and 1.63% in the average values of $\delta$/SUP 18/O and $\delta$/SUP 13/C, respectively. The relationship between $\delta$/SUP 18/O and $\delta$/SUP 13/C values was positive in interspecies of two species.

• Journal of The Geomorphological Association of Korea
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• v.24 no.2
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• pp.79-90
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• 2017

This study investigated the correlation between the diatom community and the environmental variables on the tidal flat surface of the eastern part of Gomso Bay in the West coast of Korea in order to utilize the quantitative sea level record as a basic data. 24 sediment samples at 10cm intervals downstream of the Galgok Stream were used for diatom analysis, grain size analysis and CCA. As a result of diatom analysis, marine diatoms dominated at lower altitudes and the ratio of diatoms to fresh water diatoms and brackish diatoms increased toward upland. As a result of CCA, the contribution of environmental variables was analyzed as 25.3% at altitude, 21.6% at sand, 13.3% at skewness, etc. This means that altitude above sea level has the greatest influence on the diatom composition in the tidal flat surface. It suggests that the contribution of environmental variables at altitude above sea level can be used as a basic data for the quantitative records for reconstruction of paleo-sea level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.2
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• pp.114-120
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• 2019

In the case of being contaminated with pathogenic Vibrio, shellfish pose a serious threat for public health. This study was conducted to investigate the presence of Vibrio parahaemolyticus and V. vulnificus in the seawater, bottom deposit and shellfish samples collected from the Gomso Bay, west coast of Korea. V. parahaemolyticus (30-80 CFU/g) was detected from seawater Jul. to Oct. and highest at Sep. V. parahaemolyticus was detected less than 10 CFU/g from seawater at Nov. with $14.6^{\circ}C$ of seawater temperature. V. parahaemolyticus (180-1,850 CFU/g) was detected more than 100 CFU/g from 3 kinds of shellfish, Short-necked clam Ruditapes philippinarum, Corb shell Cyclina sinensis, and Surf clam Mactra veneriformis, Jul. to Oct. and was highest in Surf clam at Oct. V. parahaemolyticus was detected less than 20 CFU/g from all tested shellfish at Nov. V. vulnificus (1.8-2.7 MPN/100 mL) was detected from seawater Jul. to Oct. and was not detected at Nov. V. vulnificus (18-236.7 MPN/100 g) was also detected from 3 kinds of shellfish Jul. to Oct. and was highest in Corb shell at Jul. V. vulnificus was not detected from all tested shellfish at Nov.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.878-884
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• 2017

It is important to understand interactions in the sediment-water environment because nitrate (N) and phosphorus (P) nutrient fluxes released into overlying water can represent a significant fraction of the total nutrient requirement for primary productivity. In this study, we analyzed and estimated benthic nutrient fluxes at the sediment-water interface, investigating environmental conditions in Gomso and Geunso Bays. Also, we compared previously reported nutrient flux data to identify regional differences. As a result, benthic nutrient fluxes in Beopsan were DIN: $6.14mmol\;m^{-2}d^{-1}$ and DIP: $0.32mmol\;m^{-2}d^{-1}$ higher than other survey sites. Sediment COD were $4.0-10.8mg/g{\cdot}dry$, and environmental deterioration was observed due to organic pollution. If no solution is found for tidal flat farm management, problems such as a decrease in aquaculture production will follow. Therefore, long-term monitoring of tidal flat environments should be pursued to enable the sustainable use of biological resources.