• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.3 s.26
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• pp.171-177
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• 2006

To illustrate the characteristics of marine environment in coastal waters of stationary fisheries, field observations were carried out in August and November, 2001. Water temperatures in Jindong Bay compared with those in Masan Bay were about $2.0^{\circ}C$ higher in August and about $0.7^{\circ}C$ in November. Salinities were lowest in the western part of Jindong Bay. It was found that salinity increased gradually from the western part of Jindong Bay to Masan Bay. Sea water in Masan Bay can be characterised as lower temperature and higher salinity, compared with those in Jindong Bay. Concentrations of suspended solids in the inner parts of Jindong Bay were higher than 15mg/L in August. Suspended solids in both regions of Jindong Bay and Masan Bay showed contrastive distributions, especially in November. That is, higher concentrations of suspended solids were found in the inner parts of Jindong Bay and off Masan Bay. Concentration of chemical oxygen demand in Masan Bay was highest, 7mg/L.

• Ocean and Polar Research
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• v.37 no.4
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• pp.295-315
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• 2015

In order to determine the spatio-temporal distribution of macrobenthic faunal communities in Jinhae Bay, quantitative faunal samples were collected seasonally at 23 sites in Jinhae Bay from February, 2011 to November, 2012. Sediment facies were found to be mud except for those at Chilcheon-do near Geoje Island. Mean values of TOC (%) ranged between 1.3 and 3.6%, and these are the highest values recorded excluding special management areas in Korea. Hypoxia occurred every summer in the whole areas of Jinhae Bay except around Geoje Island in the bay mouth. Due to the summer hypoxia, species richness, density and biomass also declined during the summer in Jinhae Bay. Opportunistic species such as Paraprionospio patiens, Sigambra bassi, Nectoneanthes oxypoda and Theora fragilis occurred as the dominant species before and after the hypoxia. However, Capitella capitata appeared as a dominant species only during the winter-spring season every year. From cluster analysis, Jinhae Bay could be divided into two sites groups: one group occupied the normoxic zone and the other one located in the hypoxic zone.

• Journal of Ocean Engineering and Technology
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• v.23 no.4
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• pp.25-31
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• 2009

To predict pollutants during the flood and dry season in Gwangyang Bay, the net-fluxes and pollutant material budgets of COD, T-N, and T-P were calculated in Gwangyang Bay using a 2-D hydrodynamic model. Calculating the net-flux for each area in Gwangyang Bay showed that the net-fluxes in regions IV, V, and VII were increasing, but those of regions II, III, and VI were decreasing. In budget calculations for COD, T-N, and T-P in Gwangyang Bay, it was estimated that during the dry season the COD is approximately 1.6 times higher than during the flood season. The T-N during the flood season is approximately 7 times higher than during the dry season. However, the material budget for T-P in Gwangyang Bay predicted that it is almost nonexistent. Moreover, the central part of Gwangyang Bay (Region IV) has the highest material budget of overall pollutants.

• ALGAE
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• v.23 no.4
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• pp.251-255
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• 2008

In Gamak Bay, Paralytic Shellfish Poisoning (PSP) was first detected from seafoods in 2003, however the toxin source is unknown yet. In this study, we report potential PSP producers of toxic dinoflagellates, describing morphology and abundance of cysts isolated from surface sediment of Gamak Bay. The most abundant type in these cysts was characterized with ellipsoidal and transparent wall identical to Alexandrium catenella and/or A. tamarense. Germination experiment of the cysts revealed that all motile cells germinated were morphologically identified as A. tamarense. This result suggests that A. tamarense may relate to PSP contaminations in Gamak Bay. Moreover, bottom water temperature in Gamak Bay is favorable for germination of A. tamarense cysts. Further studies are required to carry out the PSP monitoring for preventing the risk of PSP events that may outbreak in future at Gamak Bay.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.59-66
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• 2016

Pollution contribution rate that is effect on water quality from land based load in Masan bay was showed quantifiably for coastal water quality management by using ecological model. It was calculated by difference of water quality concentration at each points t hat is calculated by each scenarios that are presence or absence of each sources (16 points). Results show that, rivers of Northern Masan bay contributed in Masan bay COD is 20 %, T-P is 62 % at northern part and COD is 10 %, T-P is 16 % at middle part. As a result, rivers of Northern Masan bay had effect on water quality of northern Masan bay and middle Masan bay. Also, T-P load affects water quality bigger than COD load, because T-P contribution rate bigger than COD contribution rate of northern rivers. Dukdong WTTP that is land pollution source of southern Masan bay contributed in Masan bay COD is 26 %, T-P is 11% at middle part, COD is 17 %, T-P is 7 % at middle part and COD is 10 %, T-P is 1 % at outer part. It affects water quality bigger at southern and middle of Masan bay than outer bay, because residual flow of bottom flows toward inner of Masan bay nearby Dukdong WTTP.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.493-498
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• 2013

To investigate the historical record of Alexandrium spp. in southern coastal areas of Korea, two sediment cores were collected from Gamak Bay and Yeoja Bay. Germination experiments revealed that the ellipsoidal Alexandrium cysts isolated from Gamak Bay and Yeoja Bay are morphologically identical to a toxic dinoflagellate A. tamarense. The ellipsoidal Alexandrium cysts in Yeoja Bay appeared from 30 to 32 cm depth upwards (ca. 1980s), and their concentration increased around 10 to 12 cm depth (mid-1990s). Similarly, cyst concentration in Gamak Bay also increased from 40 to 44 cm depth (ca. 1990s). These results coincide with the reports of Paralytic Shellfish Poisoning caused by A. tamarense in 1980s and 1990s along the southeast coast of Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.180-189
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• 2001

This study was conducted to investigate the macrobenthic community in Ulsan Bay and Onsan Bay, in November of 1997. The density of benthic animals was 535 md./m2, and the number of species was 117. Polychaeta was the most dominant faunal group, comprising a total of 63 species, and its density was 380 md./m2 The most dominant benthic macrofauna was Cirratulrus cirratulas (2.7%), and followed by Tharyx sp. (16.6%), Ruditapes philippinarum (16.1%), Lumbrineris longifolia (10.3%) and so on. The dominant species occupied their distinct unique distribution area. Tharyx sp., R. philippinarum and Grandidierella sp.1 occurred mainly in Ulsan Bay, L. longifolia and Euchone sp. in Onsan Bay, and C. cirratulas and Cirriforimia tentaculata in both bays. By cluster analysis, study area was divided into 4 station groups: Northern Ulsan Bay (Al), the middle area of Ulsan Bay (Bl), offsea area between Ulsan Bay and Onsan Bay (Bll), and Onsan Bay (C). Northern Ulsan Bay was characterized by low species number and high density. The dominant species were C. cirratulas R. philippinarum and Tharyx sp. The middle area of Ulsan Bay was by low species number and density, and its characteristic species was Grandidierella sp.1. The offsea area between Ulsan and Onsan Bay was by high species number and low density. Onsan Bay was by high species number and high density, and its important species were L. longifolia and Euchone sp.

• Archives of Pharmacal Research
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• v.14 no.3
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• pp.271-278
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• 1991

To investigate further whether the effects of the dihydropyridine (DHP) drugs on calcium channels are related to those of these drugs on muscarinic receptors, the binding characteristics of the DHP calcium channel agonist, Bay K 8644, on muscarinic receptors and calcium channels were compared to those of the DHP calcium channel antagonists, nicardipine and nimodipine in the dog cardiac sarcolemma. Bay K 8644, nicardipine and nimodipine inhibited the specific $[^3H]$QNB binding with $K_i$ values of 16.7\mu{M}$, 3.5\mu{M}$ and 15.5\mu{M}$ respectively. Saturation data of $[^3H]$QNB binding with $K_i$ VALUES OF 16.7\mu{M}$ 3.5\mu{M}$ and 15.5\mu{M}$ respectively. Saturation data of $[^3H]$QNB binding in the presence of these DHP drugs showed this inhibition to be competitive. Bay K 8644, like nicardipine and nimodipine, blocked the binding of $[^3H]$nitrendipine to the high affinity DHP binding sites, but atropine did not, indicating that the muscarinic receptors and the DHP binding sites m but atropine did not, indicating that the muscarinic receptors and the DHP bindings sites on calcium channels are distinct. The $K_i$ value of Bay K 8644 for the DHP binding sites was 4nM. Nicardipine and nimodipine $(K_i:0.1-0.2\;nM)$ were at least 20 times more potent than Bay K 8644 in inhibiting $[^3H]$ nitrendipine binding. Thus, the muscarinic receptors were about 4000 times less sensitive than thes high afinity DHP binding sites to Bay K 8644. These results suggest that the DHP calcium agonist Bay K 8644 binds directly to the muscarinic receptors but its interaction with the muscarinic receptors is not related to its binding to the DHP binding sites on calcium channels.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.70-80
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• 2014

We carried out numerical experiments to understand sedimentary environments in Gamak Bay where is located in the center of the southern coast of Korea. Deposition rates in Gamak Bay appeared to increase in the autumn and spring whereas they appeared to decrease in the summer and winter. These seasonal variations qualitatively coincided with seasonal variations of Ignition Loss (IL) for surface sediments. Furthermore, deposition rates turned out to be prevalent compared to erosion rates in most areas of the bay. On the other hand, current measurement results at both the northeast and south mouths of the bay showed their residual components to flow into the bay. Therefore, we can conclude that contaminated materials flowing into Gamak Bay will precipitate to be deposited in the bay as long as there is no specific events such as dredging.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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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.