• 한국환경과학회지
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• 제5권3호
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• pp.347-359
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• 1996

A study was carried out on the distribution of chlorophyll a and water quality in the dry season in Yosuhae bay and adjoining sea, Southern Korea, in July of 1994. Concentration of salinity and phosphate were lower in the outer bay than in the inner bay. While nitrate and silicate were higher in the former than in the latter. We were identified with coastal waters of origin from China with the lower salinity in outer bay. The China coastal water was characteristic of high nutrients and phytoplankton biomass, such as chlorophyll a. The principal component analysis-(PCA) on the analytical data proved that high density of phytoplankton biomass , occurred under the condition of low salinity and high concentration of nissoived Inorganic nutrients. It is thought that the thermoharine structure and biological produtions of Yosuhae bay were controlled by the China coastal water in the outer bay.

• ALGAE
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• 제23권3호
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• pp.241-250
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• 2008

Since seagrasses in the coastal and estuarine ecosystems achieve high levels of production, they require high inorganic carbon and nutrient incorporation. Thus, seagrasses may play a significant role in carbon and nutrient cycling in the coastal and estuarine ecosystems. To examine growth dynamics of Zostera marina L. environmental factors such as underwater irradiance, water temperature, and salinity, and biological parameters such as shoot density, biomass, shoot morphology, and leaf productivity were measured in two bay systems (Jindong Bay and Gamak Bay) on the southern coast of Korea. While underwater irradiance did not show distinct seasonal trend, water temperature at both sites exhibited clear seasonal trend throughout the experimental period. Shoot density increased dramatically during winter due to the increased seedlings through germination of seeds in Jindong Bay and due to the increased lateral shoots in Gamak Bay. Eelgrass biomass increased during winter and decreased during summer. Maximum biomass in Jindong Bay and Gamak Bay was 250.2 and 232.3 g dry weight m–a2, respectively. Carbon incorporation into the eelgrass leaf tissues was estimated from productivity and leaf tissues carbon content. The calculated annual carbon incorporations at the Jindong Bay and Gamak Bay sites were 163 and 295 g C m–`2 y–`1, respectively. This high carbon incorporation into seagrass tissues suggests that seagrass habitats play an important role as a carbon absorber in the coastal and estuarine ecosystems.

• 한국해양학회지:바다
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• 제6권3호
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• pp.180-189
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• 2001

1997년 11월에 울산만과 온산만의 저서동물군집을 파악하기 위한 연구가 실시되었다 저서동물군집의 평균서식밀도는 535 개체/$m^2$이었으며, 출현종수는 117종이었다. 이 중 다모류가 최우점 동물군이었으며, 출현종수는 총 63종, 서식밀도는 380 개체/$m^2$이먼다. 다모류를 비롯한 저서동물은 울산만 상단과 온산항에서 가장 서식밀도가 높았으며 , 두 만의 사이 해역에서 낮았다. 저서동물중 주요 우점종은 Cirratulrus cirratulas(22.7%), Tharyx sp.(16.6%), Ruditapes philippinarum(16.1%), Lumbrineris longifolia(10.3%) 등이다. 본 조사해역의 가장 큰 특징은 우점종들의 특정 분포 해역이 뚜렷이 차이가 난다는 것으로, 울산만에서는 Tharyx sp., R. philippinarum, Grandidierella sp.1가, 온산만에서는 L. longifolia, Euchone sp.가, 그리고 두 만에 공통적으로 C. cirratulus, Cirriforimia tentaculata 가 우점하고 있다. 집괴분석 결과, 조사해역은 크게 4개의 해역-울산만 북단, 울산만 중앙역, 울산만과 온산만 사이 외해역 , 온산만-으로 대별되었다. 울산만 북단 정점군은 저서동물의 출현종수는 적으나, 서식밀도가 가장 높은 지역으로, C. cirratulus, R. philippinarum, Tharyx sp.가 주요 우점종이다. 울산만 중앙역 정점군은 갑각류 Grandidierella sp.1가 특징적으로 출현하고 있다. 울산만과 온산만 사이 외해역은 저서동물의 서식밀도가 매우 빈약한 해역이나, 출현종수는 매우 많다. 온산만 정점군은 출현종수도 많으며, 서식밀도도 매우 높다. 대표적 종은 고. L. longifolia와 Euchone sp.이다.

• Ocean and Polar Research
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• 제29권4호
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• pp.339-348
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• 2007

In this work, we compared the characteristics of three benthic biotic indices (BPI, AMBI, BIBI) which indicates the health condition of benthic communities in Masan Bay, Korea where anthropogenic impacts have been concentrated. Also we evaluated the usefulness of these benthic indices and some problems if they were applied to the Korean coastal waters. For this we used the macrozoobenthos data collected using van Veen grab ($0.1\;m^2$) at 21 sites in Masan Bay in February and August 2004. Based on the BPI values, two stations in the inner bay were found in a very hard polluted condition and three stations in the middle bay were also in a highly polluted condition. Only one station located in the bay mouth was in a normal condition. The inner bay stations showed very high AMBI values (${\geq}5.0$), indicating a highly polluted condition. The bay mouth station was assessed in a moderately polluted condition. The overall BIBI values in Masan Bay were in the range between 1.0 and 3.0. The inner bay stations showed low BIBI values (${\leq}2.0$) in the severely degraded condition. The bay mouth station with high BIBI value over 3.0 was assessed as a normal condition. All three benthos indices showed that macrozoobenthic communities in the inner bay were in a seriously polluted condition all year round, and macrobenthic faunas in the bay mouth seemed in a bad healthy condition (slightly polluted) based on AMBI during summer season. These three benthic biotic indices showed the similar assessment result, and thus we consider that each of them is a useful tool for the assessment of coastal benthic ecosystems under the organic enrichment in sediment.

• 환경생물
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• 제18권2호
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• pp.227-235
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• 2000

As a part of basic investigation to Fishery Purge Project for the Special Administrative in Chollanamdo Province, the sedimentary environmental characteristics of Yoja Bay at 15 stations were studied. The analysis was carried out in July, 1998, through studies of Loss On Ignition (LOI) by depth, Total Sulfide (T-5), Chemical Oxygen Demand (COD) concentrations and Grain-size distribution. The LOI value was found to be 6.20-12.20% (mean of 8.89%), with the neighboring Sunhakri and Haksanri areas showing slightly higher values. These values were similar to the LOI values observed in the Hansan-Koje Bay and Jinju Bay areas on the southern coast of Korea. T-S and COD concentrations were found to be, respectively, 0.060-0.104 mg/gㆍd (mean of 0.052 mg/gㆍd) and 5.53-29.71 mg/gㆍd(mean of 13.24 mg/gㆍd), not exceeding eutrophication limits. T-S concentration was especially high at stations close to the central areas of the bay and inland areas, which caused by organic matter input from the nearby agricultural areas. COD concentration was very high at stations nearby the bay entrance and Doonbyungdo, but the mean value was lower than that of Hansan-Koje Bay. This leads us to believe that the level of pollution in Yoja Bay is not significant. The prevailing sediment composition was mud, consisting of 61.38% silt and 34.87% clay. [Sediments in Yoja Bay, Loss On Ignition, Total Sulfide, Chemical Oxygen Demand, Grain-Size Distribution].

• 한국환경과학회지
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• 제8권2호
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• pp.189-195
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• 1999

Determining factors and temporal & spatial characteristics of COD(Chemical Oxygen Demand) at the sea surface in Jinhae bay have been examined by using seasonal data, taken at twenty six stations over the whole bay during 1989~1994 by NERDA. The data have been analyzed in terms of long term means, anomalously large values. Jinhae bay is divided into three regions based on the time mean : mouth of Jinhae bay, inner sea of Masan bay, western sea of Jinhae bay called region 1,2 and 3, respectively. The horizontal distribution of the long term mean of COD at each station is similar to those of nitrogen and phosphorus. Characteristics of whole mean variation in the year shows high range of variation in region 2. It was appear to decreases every year in whole trend. Factors determining seasonal variation in whole COD mean are relative to salinity and nutrient, affected by precipitation in summer. Spatial variation shows high range of fluctuation in region 2 compare to other region. Factors determining of spatial variation of COD was appear to nutrient, affected by pollutant load of land area and bottom sediment. The long term mean of COD at each station is closely related with thats of nutrients. The correlation coefficient between COD and nitrogen, phosphate phosphorus was found to be high as 0.75, 0.78, respectively. Anomalously large COD was observed 14 times at 6 stations. These stations are located in inner sea of Masan bay(Region 2) and Songjeong bay(Region 1). The seasonal frequency of the observed anomalous COD is large in April, and other seasons are much the same.

• 한국패류학회지
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• 제15권2호
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• pp.71-79
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• 1999

To develop new products for aquaculture, which fishermen at South Sea can get high income, after bay scallop was transplanted from Sandong province in China from October 17, 1996 to March 18, 1997 at Duekrang Bay in Janghung gun and Kamak Bay in Y대녀 City on Chollanam province, Sumjin river estuary in Hadong gun and Gejae Bay in Keoje city on Kyongsangnam proince. Temperature was decreased from 20.5$^{\circ}C$ to 5.1$^{\circ}C$ in February and then it was increased to 12.0 in March. Ranges of salinity, DO and Chlorophyll-a were 22.40-34.70 psu, 5.24-9.77 mg/l and 1.27-22.28 $\mu\textrm{g}$/l, respectively, and low temperature, sudden changes of salinity and low concentration of chlorophyll-a influenced the growth of bay scallop. bay scallop in the rearing period showed the fastest growth from October 17 to November 18 through the every size rages, while it grew slowly or stopped growing from December 18 to March 18. Among 4 transplanted areas, young scallop at Duekrang Bay showed the fastest growth and then Kamak Bay, Gejae Bay, Sumjin estuary in order. The daily growth rate of young scallop in the middle size range (5.70%) was higher than those in large (2.07%) and small (5.49%) size range. The meat weight index showed the highest in December. Survival rates from October to December were high, not related to the size ranges, but survival rate of the small young scallop from January to March was higher than Those of the rest. As the Result, transplanted bay scallop at South Sea was shown to grow by the middle of December (around 1$0^{\circ}C$ temperature).

• 환경영향평가
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• 제12권5호
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• pp.341-348
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• 2003

Seasonal characteristics of water quality and effect of the freshwater discharge during open the tide embankment in Haechang Bay were evaluated. In the freshwater, where interior of the tide embankment, COD and Chl-a exceeded about 4mg/L and $10mg/m^3$, respectively, independent of season, while in the seawater they showed high values in April and July in contrast to the other period due to input of freshwater and increase of phytoplankton, respectively. The content of seawater inorganic nitrogen maintained a relatively high level at inner part of the bay, whereas high values of inorganic phosphorus content was distributed at all over the bay. The limiting factor for algal growth was nitrogen with respect to the N/P ratio. The compass of influence by the freshwater discharge in April was quite different with water pollutants. As a result of the salinity variation with time, the freshwater extended strongly to offshore from the surface layer without mixing with depth when open the tide embankment, and reached within about one hour at a station which is 3.5km from the tide embankment. To effective water quality management of Haechang Bay, discharge rate and pollutant loads should be controlled.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.483-486
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• 2006

The study describes the monitoring of the Bay of Bengal as a ballast water exchangeable sea using MODIS/Aqua-derived diffuse attenuation coefficient (K(490)) synchronized with in situ ballast water sampling and analysis along the LNG carrier's route between Japan and Qatar from 2002 to 2005. Based on the relationship between K(490) and corresponding in situ plankton cell densities, the Bay of Bengal is recognized as a ballast water exchangeable sea to meet the regulation of ballast water performance standard of International Maritime Organization (IMO). Furthermore the Bay of Bengal with more than 200m depth and more than 200 nautical mile distance from shore is extracted based on the regulation of ballast water exchange area of IMO. However, an anomalously high K(490) area is found off the coast of Sri Lanka during the northeast monsoon in 2005, which corresponds higher cell densities than the criterion set by the regulation of IMO. The phenomenon of high cell density in the Bay of Bengal seems to be related with the phytoplankton bloom during the northeast monsoon. Seasonal and annual variability of phytoplankton bloom will be investigated to establish an early routing system for avoiding the high cell density area in advance.

• 한국환경과학회지
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• 제15권9호
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• pp.819-827
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• 2006

We study on the dynamic interaction with a simulated physical-biological coupled model response to nutrient reduction scenario in Jinhae Bay. According to the low relative errors, high regression coefficients of COD and DIN, and realistic distribution in comparison to the observation, our coupled model could be applicable for assessing the marine ecosystem response to nutrient input reduction in Jinhae Bay. Due to the new construction and expansion of sewage treatment plant from our government, we reduce 50% nutrient inputs near Masan Bay and sewage treatment plant. COD achieves Level II in Korea standard of the water quality from the middle of the Masan Bay to all around Jinhae Bay except the inner Masan Bay remaining at Level III. When our experiment reduces 50% nutrient inputs near Masan Bay and Dukdong sewage treatment plant simultaneously, COD decreases to about 0.1-1.2 mg/L $(128^{\circ}30'{\sim}128^{\circ}40'\;E,\;35^{\circ}05'{\sim}35^{\circ}11'\;N)$. The COD from the middle of the Masan Bay to Jinhae Bay achieves Level II.