• 수산해양기술연구
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• 제56권4호
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• pp.322-339
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• 2020

Temporal and spatial fluctuations of surface water temperature in Yeosu Bay for the period from 2010 to 2011 were studied using the data from temperature monitoring buoys deployed at 32 stations in the south coast of Korea. Temperatures in the northern part of the bay are higher in summer and lower in winter than in the southern part of the bay. The lowest and highest temperature of the annual mean are found at the eastern coast of POSCO and at the west of Dae Island, respectively. Cold water masses appear at estuarine area when the discharge of Sumjin river is affluent. Amplitude of temperature fluctuation whose period is less than semi-diurnal is largest at Hadong coast and around Dae Island. Spectral analysis of surface water temperature shows a significant peak at a periodic fluctuation of 0.5 to 24 days and about 15-day period of predominant fluctuation is most frequent in Yeosu Bay. From the cross-correlation analysis of temperature fluctuations, Yeosu Bay can be classified into six areas; the south area affected by South Sea of Korea, the mixed area in the center of the bay, the estuarine area affected by river discharge at the north of the bay, the hot waste water area near Hadong coast, the area around Dae Island and the area near Noryang Channel affected by the water in Jinju Bay, respectively.

• Environmental Engineering Research
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• 제15권1호
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• pp.15-21
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• 2010

This study was conducted to evaluated seawater bacteria and their seasonal characteristics in the arsenic contaminated coastal seawater of Yeosu Bay, the Republic of Korea. Arsenite-oxidizing bacteria play an important role in the seawater of the arsenic contaminated bay, with a variety of arsenic resistance system (ars) genotypes being present during summer. Specifically, Bacillus sp. strain SeaH-As22w (FJ607342), isolated from the bay, were found to contain the arsB, arrA and aoxR type operons, which are involved in arsenic resistance. The isolated bacteria showed relatively high tolerance to sodium arsenite (III; $NaAsO_2$) at concentrations as high as 50 mM. Additionally, batch seawater experiments showed that Bacillus sp. strain SeaH-As22w completely oxidized 1 mM of As (III) to As (V) within 10 days. Ecologically, the arsenic-oxidizing potential plays an important role in arsenic toxicity and mobility in As-contaminated coastal seawater of Yeosu Bay during all seasons because it facilitates the activity of Bacillus sp. groups.

• Fisheries and Aquatic Sciences
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• 제24권1호
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• pp.41-52
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• 2021

Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

• 한국환경과학회지
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• 제15권10호
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• pp.919-928
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• 2006

The present study applied an atmospheric flow field model in Gwangyang-Bay which can predict local sea/land breezes formed in a complex terrain lot the development of a model that can predict short term concentration of air pollution. Estimated values from the conduct of the atmospheric flow field were used to evaluate and compare with observation data of the meteorological stations in Yeosu and the Yeosu airport, and the effect of micrometeorology of surround region by the coastal area reclamation was predicted by using the estimated values, Simulation results, a nighttime is appeared plainly land breezes of the Gwangyang-bay direction according to a mountain wind that formed in the Mt. of Baekwooun, Mt. of Youngchui. Land winds is formed clockwise circulation in the north, clockwise reverse direction in the south with Gangyang-bay as the center. Compared with model and observation value, Temperature is tend to appeared some highly simulation value in the night, observation value in the daytime in two sites all, but it is veil accorded generally, the pattern of one period can know very the similarity. And also, wind speed and wind direction is some appeared the error of observation value and calculation results in crossing time of the land wind and sea land, it can see that reproducibility is generally good, is very appeared the change land wind in the nighttime, the change of sea wind in the daytime. And also, according to change of the utilization coefficient of soil before and after development with Gwangyang-Bay area as the center. Temperature after development was high $0.55\sim0.67^{\circ}C$ in the 14 hoots, also was tend to appear lowly $0.10\sim0.22^{\circ}C$ in the 02 hours, the change of u, v component is comparatively tend to reduced sea wind and land wind, it is affected ascending air current and frictional power of the earth surface according to inequality heating of the generation of earth surface.

• 한국수산과학회지
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• 제18권2호
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• pp.157-165
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• 1985

어장환경관리의 기본자료를 얻기 위하여 1984년 6월중에 가막만에서 실시한 해양관측자료를 가지고 상기만의 밀물과 썰물시 해황분포를 알아보고 그 특성이 지형적 요인에 의해 크게 좌우됨을 살폈다. 가막만은 두개의 만구와 돌출한 도서 및 지세 등 그 지형적 여건에 의해 4개의 특징적 수괴가 나타난다. 내만수는 내륙의 영향이 강한 정체성을, 여수항수는 섬진강 영향이 큰 저염의 외해성을, 만외수는 해저난류 또는 와류발생으로 수직균질한 외해성을, 중간수는 만외수와 내만수의 중간성격이다. 밀물때 양만구로 유입한 해수는 대략 소경도와 항대를 연결하는 선에서 만난다. 군내리근에서는 지형성 와류 혹은 해저난류가 발생하는 것으로 추정되는데, 밀물때는 해수의 침강이, 썰물때는 저층수의 특성치가 보여지며 그 크기는 약 3 km 까지 뻗친다.

• 수산해양기술연구
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• 제30권3호
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• pp.142-149
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• 1994

In order to investigate the environmental properties of set net grounds located in the coastal waters of Yeosu. The current in the vicinity of set net grounds was observed by drogue and current meter in 1990 and 1992. The results obtained are summarized as follows: The direction of tidal current at the north enterance of Yeosu bay was southerly in ebb and northwesterly in flood without the distiction of the neap tide and the spring tide. In spring tide the maximum Velocity of the tidal current was 68 cm/sec in ebb and 66 cm/sec in flood. In neap tide the maximum velocity of the tidal current was 37 cm/sec in ebb and 35 cm/sec in flood. And so the direction of residual current was the south ward mainly and 21 cm/sec. The direction of tidal current at set net fishing grounds was southwesterly in ebb and westerly or northwesterly in flood. Regardless of the distinction of neap and spring. The maximum velocity of the current in spring tide was 50 cm/sec in ebb and 40 cm/sec in flood and that in neap was 28 cm/sec in ebb and 25 cm/sec in flood. In spring tide the speed vector along the major axis of semidiurnal tide component was three times as large as diurnal tide. In neap tide, however, the speed vector was about 50% less then that in spring tide, and the semidiurnal tide and diurnal tide were equal in the size of current ellipse and the direction of major axis. The sea area had a southwesterly residual current. 11 cm/sec in spring tide and 7 cm/sec in neap tide. According to the result of drogue tracking, the vicinity of set net fishing ground had a southerly residual current which formed in Yeosu Bay and a weak westerly residual current toward Dolsando from Namhedo. Therefore, set net fishing ground in coastal water of Yeosu was distributed in boundary of inner water which formed from Seamjin river and offshore water supplied from the vicinity of Sorido and Yochido.

• 한국수산과학회지
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• 제8권2호
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• pp.73-84
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• 1975

1) 호남정유공장 폐수 및 부근에 버려진 유류와 사포리의 원유저장 탱크에서 흘러나온 유류는 썰물을 따라 여수해만 쪽으로 흘렸다가 밀물을 따라 백합양식장으로 바로 흘러 들어가며 대조일의 조수에서 $6\~8 $시간만에 양식장 전역에 이른다. 2) 지점 9, 10은 강수의 혼입이 약간 많은 수질인 즉 pH가 상대적으로 낮고 암모니아 질소가 많고 n-헥산 가용물질량이 적은 편이지만 지점 $6\~10$은 수질이 동일하다. 3) 폐수배출관이 있는 지점 2에서의 수질은 표층, 중층, 하층에 별다른 차가 없다. 4) 호남정유공장 폐수에 있어서 유해성분으로서 pH, 황화물이 배출기준 보다 높고, COD, 페놀, n-확산 가용물질량은 배출 기준보다 낮은 편이나 n-헥산가용물질량은 상당히 높은 수준이라고 본다. 5) 호남정유공장 폐수에 함유되어 있는 유해성분의 각 수역에서의 농도는 n-확산가용성 이외는 정상해수와 별로 다른 바 없다. 그러나 n-확산가용물질의 농도는 정상해수보다 높다. 6)해역에서의 n-헥산가용물질량 및 COD 값이 Table 1에서 볼 때 공장에 가까운 수역일수록 높은 것으로 보아 백합양식장에서의 이들 성분농도가 높은 원인은 해구유동도 참작할 때 호남정유공장의 폐수 및 누출유에 있다고 본다.

• 해양환경안전학회지
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• 제28권2호
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• pp.201-211
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• 2022

연구대상 해역은 노량수로를 중심으로 서측에 광양만 권역(여수해협 포함), 동측에 진주만 권역(강진만, 사천만 포함)이 위치하고, 연구대상 해역에 위치한 여러 하천에서 유출되는 유출수가 이들 만으로 유입되고 있으며, 특히 홍수시에는 광양만 권역은 섬진강의 하천유출수가, 진주만 권역은 가화천(남강댐 방류)의 하천유출수가 대량으로 유입되고 있다. 광양만 권역과 진주만 권역은 노량수로라는 협수로로 연결되어 있으며, 섬진강과 가화천의 하천유출수 또한 노량수로를 통해 서로 영향을 주고 있다. 연구대상 해역에 위치한 섬진강과 가화천을 포함한 51개 하천의 하천유출수로 인한 평수시와 50년빈도 홍수시의 해수교환율, 체류시간 특성을 입자추적 실험을 통해 파악하고자 하였다. 또한 홍수시 섬진강과 가화천의 하천유출수가 미치는 영향을 파악하기 위한 실험을 추가로 수행하였다. 수치실험 결과, 평수시와 홍수시 모두 광양만 권역에 투하한 입자는 노량수로를 통해 진주만 권역으로 이동하는 것으로 나타났고, 노량수로를 통해 진주만 권역에서 광양만 권역으로 이동하는 입자는 상대적으로 작은 것으로 나타났다. 30일 후 각 실험안별 해수교환율은 광양만 권역은 44.40~67.21%로 나타났고, 진주만 권역은 각각 50.37~73.10%로 나타났고, 각 실험안별 평균 체류시간은 광양만 권역은 7.07~15.36일로 나타났고, 진주만 권역은 6.45~12.75일로 나타났다. 그리고 홍수시에 해수교환을은 증가하고, 체류시간은 감소하는 것으로 나타났다. 광양만과 진주만 권역에서의 해수순환 구조를 살펴보기 위해 두 폐쇄성 해역에 대해서 7개 내부 영역과 5개 외부 영역에 대한 30일 동안의 단면유량 flux를 산정하였다. 그 결과, 평수시와 홍수시 모두 전반적으로 광양만 권역에서 진주만 권역으로 유량 flux가 이동하는 것으로 나타났다. 홍수시 유량을 적용할 경우 연구대상 해역의 유량 flux의 주 흐름 경로는 섬진강 하천유출수가 여수해협을 거쳐 외해로 이동하는 흐름과 가화천 하천유출수가 사천만, 진주만, 대방수로를 거쳐 외해로 이동하는 흐름으로 나타났다.

• Asian Journal of Atmospheric Environment
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• 제7권3호
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• pp.139-151
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• 2013

The purpose of this study is to understand distributional characteristics in the atmospheric concentrations of $O_3$ and its precursors based on data taken at the southern Korean coast. The average $O_3$ concentration in the high altitude was found to range from 32.3 to 90.8 ppb with a maximum concentration of 132 ppb. The ambient $O_3$ concentration was high at altitudes of 1000 m and 500 m above the southern sea near Gwangyang Bay and an industrial area containing emission sources. The daily mean concentrations of $NO_y$ and CO were 6.7-24.2 ppb and 0.152-0.487 ppm, respectively. During the aerial measurement period, the highest mean concentration of $O_3$ was observed on June 1. The aerial measurement results showed that the maximum ozone concentration was observed to be 132 ppb in the high altitude the southernmost part of Yeosu. The measurement of vertical wind fields in the air indicated that $O_3$ formed in the southernmost part of Yeosu was transported by strong southwesterly winds to the northeast of Gwangyang Bay. This led to a ground $O_3$ concentration of over 100 ppb in Jinju, the northeastern part of Gwangyang Bay. On August 9, when the maximum $O_3$ concentration was 50 ppb, the measurement results showed that $O_3$ concentrations were relatively low compared to other days. In particular, low $NO_2$ and TVOC concentrations were observed, both of which serve to form $O_3$ in photochemical reactions.

• 한국환경과학회지
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• 제15권10호
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• pp.951-960
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• 2006

The eco-hydrodynamic model was used to estimate the environmental capacity in Gamak Bay. It is composed of the three-dimensional hydrodynamic model for the simulation of water flow and ecosystem model for the simulation of phytoplankton. As the results of three-dimensional hydrodynamic simulation, the computed tidal currents are toward the inner part of bay through Yeosu Harbor and the southern mouth of the bay during the flood tide, and being in the opposite direction during the ebb tide. The computed residual currents were dominated southward flow at Yeosu Harbor and sea flow at mouth of bay, The comparison between the simulated and observed tidal ellipses at three station showed fairly good agreement. The distributions of COD in the Gamak bay were simulated and reproduced by an ecosystem model. The simulated results of COD were fairly good coincided with the observed values within relative error of 1.93%, correlation coefficient(r) of 0.88. In order to estimate the environmental capacity in Gamak bay, the simulations were performed by controlling quantitatively the pollution loads with an ecosystem model. In case the pollution loads including streams become 10 times as high as the present loads, the results showed the concentration of COD to be $1.33{\sim}4.74mg/{\ell}(mean\;2.28mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality In case the pollution loads including streams become 30 times as high as the present loads, the results showed the concentration of COD to be $1.38{\sim}7.87mg/{\ell}(mean\;2.97mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality. In case the pollution loads including streams become 50 times as high as the present loads, the results showed the concentration of COD to be $1.44{\sim}9.80mg/{\ell}(mean\;3.56mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality.