• The Korean Journal of Malacology
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• v.16 no.1_2
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• pp.49-54
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• 2000

The growth of short neck calms, Tapes philippinarum was compared between two areas, Songdo in Kamak Bay and Sudo in Chinhae Bay from April 1999 to March 2000. The short neck clams in Kamak bay grew from 13.84${\pm}$0.04 mm to 35.43${\pm}$1.22 mm in shell length, while those in Chinhae bay grew from 13.84${\pm}$0.04 mm to 31.91 ${\pm}$1.72 mm in 12 months. Shell height, shell breadth and total weight of the short neck clams in Kamak bay were also greater than those from Chinhae bay. Bottom quality of Chinhae bay showed negative skewness, and that of Kamak bay was positive skewness of Chinhae bay seems to be caused by the effect of strong tidal current. This may indicate that Kamak bay is better area than Chinhae bay for the culture of the short neck clams.

• Journal of the korean society of oceanography
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• v.35 no.2
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• pp.109-123
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• 2000

Depositional processes of fine-grained sediments were investigated on the basis of sediment transport vector analysis and identification of benthic foraminiferal assemblages in Yoja Bay, southern coast of Korea. The bay is a semi-enclosed embayment where extensive mud flats occur with a width up to about 4 km. Most surface sediments are poorly sorted (sorting values: 1.9-3.0 ${\phi}$) mud and silt (mean grain size: 6.0-8.7 ${\phi}$), except for the tidal inlets with basement rocks locally exposed. Grain-size distribution shows a fining tendency toward the basin center near the Yoja Island, implying a possible existence of turbidity maximum and relatively rapid settling of fine-grained sediments. The agglutinated foraminiferal taxa are dominant in the inner bay and decrease in abundance toward the mouth of the bay. Species diversities are higher in the outer bay, due to mixing of the offshore faunas with those of the bay. Four groups of benthic foraminiferal assemblages, identified by cluster analysis, represent the bay. Biofacies I and ll with relatively lower diversities are dominated by Ammobaculites exiguus and Ammonia beccarii, suggestive of influx of fresh water. In contrast, biofacies III and IV with relatively higher diversities include increased amounts of calcareous genus Elphidium and Quinquelocuzina, accounting for strong influence of sea water from the offshore. The fluvial discharge in summer floods appears to develop a bay-wide, clockwise lateral circulation in Yoja Bay, a typical of well-mixed estuaries. Accordingly, the foraminiferal assemblages of the surface sediments well show a sign of this circulation. The dominant inflow of the offshore water into the western part of the bay has resulted in more extensive muddy tidal flats compared to the eastern narrower counterpart.

• ALGAE
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• v.23 no.3
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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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.151-156
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• 2003

Spatio-temporal distribution of dinoflagellate cysts was monthly investigated at 6 stations in Gamak Bay, the southern Korea from April 2000 to April 2001. A total of 37 species of dinoflagellate cysts belonging to 22 genera were identified. The temporal changes of species number fluctuated with an annual mean of 8 species, 1 species at Stn. 6 in July in the middle Gamak Bay and 17 species at Stn. 2 in June southern Gamak Bay, but 11 to 20 species occurred in the northwestern Gamak Bay all the year round. The major species were Brigantedinium cariacoense, Brigantedinium simpler, Brigantedinium spp., Protoperidinium americanum, Quinquecusphix concretum, Selenopemphix quanta, Scrippsiella trochoidea, Spiniferites bulloideus, Spiniferites spp., Stelladinium reidii, Votadinium carvum, and Polykrikos sp. of kofoidii. The dominant species of dinoflagellate cysts was not evident in the over-all study areas, but in the northwestern Gamak Bay Brigantedinium spp. and Protoperidinium americanum were dominant $(50.4-76.0\%)$ during the study periods. Abundance of dinoflagellate cysts on the surface sediment in the Gamak Bay ranged from 21 cysts/g dry at Stn. 6 in July to 4,322 cysts/g dry at Stn. 4 in August with an annual mean of 688 cysts/g dry. Especially, the highest value occurred in the northwestern Gamak Bay. Heterotrophic species was more abundant than autotrophic species on the surface sediment. In particular, the former occurred in $75-94\%$ in the northwestern Gamak Bay throughout the year. The northwestern area was very different from other area in species number, dominant species and abundance of dinoflagellate cysts. It is mainly due to water stagnation and eutrophication in the area. And the seasonal abundance of dinoflagellate cysts in Gamak Bay was inversly related to water temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.223-230
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• 2010

To compare seed collection and the growth of Anadara subcrenata in Suncheon and Boseong Bays, environmental factors and the growth of larvae and spats were investigated from August 2008 to July 2009 in commercial farming sites in both bays. The variation in water temperature in both bays was similar, but the salinity was lower in Suncheon Bay than in Boseong Bay. The chlorophyll-a content was higher in Suncheon Bay due to the large inflow of freshwater. The density and shell length of A. subcrenata larvae did not differ significantly between the two bays. However, the relative growth of shell height to shell length was significantly higher in Suncheon Bay (P<0.05). The growth of A. subcrenata spats attached to a collector was significantly faster in Suncheon Bay (P<0.05). The spats in Suncheon and Boseong Bays grew to 24.3 and 21.0 mm in shell length, respectively, within 1 year after spawning, and the shell length reached 35.6 and 34.8 mm, respectively, within 2 years of spawning. The initial spats density was higher in Boseong Bay, but the growth of spats was better in Suncheon Bay. The faster growth of A. subcrenata in Suncheon Bay can be explained by the high chlorophyll-a content in this bay. Based on the low survival (%) and slower growth rate of spats in Boseong Bay, the commercial culture density of A. subcrenata in Boseong Bay should be reduced to the optimum level of the carrying capacity.

• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.146-148
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• 2007

In this paper, we designed the bay control unit that is based on the microprocessors and integrates with the new technology of electrical, electronic, and mechanical fields. Nowadays the customers have required much more integrates multi protection relay, monitoring, control devices and power management for better and easier maintenance, performance, electrical system analysis and communication according to new trend of switchboard. This bay controller supplies those requirements of customers with easy handling and operation. This bay controller provides a graphic display with rear-lit liquid crystal LCD and push buttons as kinds of HMI. This bay controller provides the parameter setting program, various editors and fault recording and analysis program on Windows/95/98/NT/2000/XP for HMI. In addition, this bay controller can be set manually and this manual setting function helps user to interface easily.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.345-358
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• 2003

Jindong bay at the northwestern part of Jinhae bay suffers from the occurrence of red tides in summer every year. In order to study the management methods of coastal environments, an ecological numerical model has been developed. The model experiments was forecasted that the load of nutrients from the land and field concentration will be cut down per 10% each. When we cut down 57.2% nitrogen load in the inner bay and 38.4% phosphorous load in the outer bay of bottom layer of the nutrients load from land and field concentration, the seawater quality standard levels up first grade. When we cut down 86.5% nutrients in the inner bay and 93.0% nutrients in the outer bay, the concentration of chlorophyll a decreases below 3.2 $\mu\textrm{g}$/(equation omitted)(an individual concentration of phytoplankton : 10,000cel1/ml), i.e. the red tides do not occur.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.260-268
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• 1998

A flow pattern and water exchange in Sagami Bay is examined using a barotropic hydraulic model. In the model experiments, the volume transports of the Kuroshio Through Flow were changed with time. The results of the model experiments show that when the volume transport is increased with time, water mass and vorticity are transferred to the inner part of the bay by wakes from the western part of the bay. In the case of decrease, as the wakes are ceased, the inner cyclonic circulation water is discharged to the outside of the bay by its southward extension through the Oshima eastern channel. It is found that the water exchange by the short-term variation of volume transport in time is about 20% of all the bay water.

• Journal of Navigation and Port Research
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• v.26 no.2
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• pp.227-233
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• 2002

Recently, the water pollution of coastal sea area including harbor, bay and inland sea has been very serious and it causes u\\various environmental impacts. In this study, water flow system of Danghnag Bay, which has the narrow and long topographical characteristics with the narrow bay mouth and its flow is influenced principally by the tidal current, is investigated experimentally and numerically. In order to understand the tidal system of Danghang Bay, harmonic analysis is performed based on measured tidal range and flow velocity. In addition, numerical model for tidal exchange is developed considering conditions of Danghang Bay. Calculated results show good agreement with measurement. Lastly, based on the proposed numerical model, exchange ratio of seawater volume in Danghang Bay is predicted.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.4
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• pp.65-75
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• 2000

The roles of environmental factors affecting on heterotrophic bacterial distribution at Hangam Bay and Masan Bay in which occurred frequently red tide, during June to November 1996 were investigated. The aquatic environment of Masan Bay and Haengam Bay showed difference in the contents of inorganic nutrients. Haengam Bay may be defined as nitrogen limited aquatic environment. On the other hand, Masan Bay appeared to the appropriate N/P molar ratio of mean 15.9 during the periods of study. By the results of simple regression, chlorophyll a showed significant correlation with precipitation (r=0.813, P<0.05) and phosphorus (r=0.846, P<0.05) at Haengam Bay, but not showed significant correlation with parameters at Masan Bay. The heterotrophic bacteria showed significant correlation with many environmental parameters at Masan Bay (Precipitation, r=0.990, P<0.01 : NO₃-N, r=0.901, P<0.05 : Dissolved inorganic nitrogen, r=0.899, P<0.05 ; N/P molar ratio, r=0.952, P<0.05 : Salinity, r: -0.934, P<0.05) than Haengam Bay (SiO₃-Si, r=0.960, P<0.01). By the results of multiple regression, the chlorophyll a was varied with only 2 factors in Masan Bay (R²=0.100) and 3 factor in Haengam Bay (R²=0.903). The major factor which affected to chlorophyll a was SiO₃-Si (R²%=67.8) in Masan Bay, and -N/P (R²%=37.6) in Haengam Bay. The heterotrophic bacteria were varied with 4 factors in Masan Bay (R²=100) and 2 factor in Haengam Bay (R²%=0.878). The major factor, which affected to heterotrophic bacteria, was SiO₃-Si (R²%=42.3) and salinity (R²%=32.1) in Masan Bay, and SiO₃-Si (R²%=76.3) in Haengam Bay. Resultingly, the influx of freshwater in Masan and Haengam Bay was enriched in inorganic nutrients, and plays an important role in the change of heteroterophic bacteria and chlorophyll a during early summer to autumn.