• Ocean Science Journal
• /
• v.40 no.3
• /
• pp.119-125
• /
• 2005

Qualitative and quantitative composition of meiobenthos was studied in Amursky Bay (Peter the Great Bay, the East Sea). Ten taxonomic groups were found, where nematodes were dominant. Density of meiobenthos in ground sediments of the Bay were not uniform, and the average density was measured at $126.4{\pm}62.3ind.mo^{-2}$. 56 species of nematodes were detected, and dominant species were Sabatieria palmaris, Paracanthonchus macrodon, Sphaerolaimus limosus, S. gracilis and Oncholaimium ramosum. Five taxocenes of nematodes were allocated based on the results of cluster analysis and species domination according to density. Low diversity in species composition of nematodes was noted in the northwestern part of the Bay, which is a zone of desalination, and in the eastern part, which is exposed to household drains.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2002.03a
• /
• pp.205-218
• /
• 2002

Recently, the water pollution of coastal sea area including harbor, bay and inland sea has been very serious and it causes various environmental impacts. In this study, water flow system of Danghang 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 Ray. Calculated results show good agreement with measurements. Lastly. based on the proposed numerical model, exchange ratio of seawater volume in Danghang Bay is predicted.

• Journal of Environmental Science International
• /
• v.7 no.6
• /
• pp.833-843
• /
• 1998

It is noted that the red tides and the oxygen-deficient water mass are extensively developed in Masan Bay during summer. The nutrients mass balance was calculated in Masan Bay, using the three-dimensional numerical hydrodynamic model and the material cycle model. The material cycle model was calibrated with the data obtained on the field of the study area in June 1993. The nutrients mass balance calculated by the combination of the residual currents and material cycle model results showed nutrients of surface and middle levels to be transported from the inner part to the outer part of Masan Bay, and nutrients of bottom level to be transported from outer part to inner part of Masan Bay. The uptake rate of DIN in the box A1(surface level of inner part) was found to be 337. 5mg/$m^3$ㆍday, the largest value in all 9 boxes and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1, and the regeneration rate of DIN was found to be 78.2mg/$m^3$ㆍday in the box A3(bottom level of inner part), and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1. The regenerations of DIN and DIP in the water column of the entire Bay were found to be 7.66ton/day and 760kg/day, respectively. And the releases of DIN and DIP from the sediments of the entire Bay were found to be 2.86ton/day and 634kg/day, respectively. The regeneration rate was 2.5 times as high as the release rate in DIN, and 1.2 times in DIP. The results of mass balance calculation showed not only the nutrients released from the sediments but the nutrients regenerated in water column to be important in the control and management of water quality in Masan Bay.

• The Journal of Fisheries Business Administration
• /
• v.48 no.2
• /
• pp.33-51
• /
• 2017

The purpose of this study is to estimate conservation value of fisheries resource protected area by the double-bounded dichotomous choice contingent valuation method. The data in this analysis come from a survey of respondents of resident in fisheries resource protected area using a proportional stratified sampling from the population. The questionnaires covered all the 5 fisheries resource protected area and the sample size of every protected area was 120 questionnaires. The survey period was from August to October in 2016. Above all, the average willingness to pay amount(WTP) per person of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, Cheonsu bay is estimated \6,215, \13,215, \6,405, \9,785, and \10,390 respectively. And, the total value of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, and Cheonsu bay is evaluated \108.8 billion, \357 billion, \118 billion, 210.2 billion, \ 245.8 billion respectively. Moreover, the yearly value of Namhae-Tongyoung I, Namhae-Tongyoung II, Jindong bay, Hansan bay, and Cheonsu bay is evaluated \6 billion, \19.6 billion, \6.5 billion, 11.6 billion, \ 13.5 billion. In conclusion, fisheries resource protected area has the higher conservational value. Consequently, it is essential for now or future generation's use of fisheries resources. In light of the fisheries resource protected area's value and importance, this should be promoted to the public including the local community who utilizes fisheries resource protected area wisely. Also, this suggests that the policy for fishery resource's creation and management is needed in fisheries resource protected area.

• 한국해양학회지
• /
• v.21 no.1
• /
• pp.56-71
• /
• 1986

In order to clarify the influence of environmental factors on the phytoplankton cmmunity in Kyeonggi Bay, the hydrological and water quality data were obtained from 20cruises from May, 1981, to September, 1982 in this bay. Physical conditions at the mouth of the bay are more stable than those at the head of the bay. Temperatures and salinities of the upper part of the bay show great seasonal fluctuations due to the river discharge. By the extending effects of freshwater, a weak two-layer flow system is formed from the upper part of the bay to Palmi Island. In summer thermal stratification are formed in the middle and outer parts of the bay. In winter, However, the temperature shows no vertical temperature gradient. The inner bay and the vicinity area of Incheon Harbour are relatively polluted and eutrophicated due to both the runoff of freshwater from the Han River and the waste discharge from Incheon industrial complex. However, except the polluted area, the study areas are well oxygenated with more than 90% saturation.

• Ocean and Polar Research
• /
• v.27 no.4
• /
• pp.381-395
• /
• 2005

The spatial distributions of macrobenthic communities in Masan Bay were investigated during summer and winter, 2004. A total of 104 species were sampled with mean density of $448ind./m^2$ and biomass of $77.1g/m^2$ in winter. In summer, a total of 107 species occurred with $485ind./m^2$ and a biomass of $94.5g/m^2$. The most dominant species in winter were Paraprionospio pinnata (24.2%) among polychaetous worms and Theora fragilis (14.1%) among molluscs, but they were replaced in summer by Prionospio chirrifera (20.4%) and Lumbrineris longifolia (14.5%). The difference in species composition and abundance of benthic communities between the two seasons was due to the hypoxia in the bottom layer of the inner bay during summer, which defaunated the macrofauna of the sediments. In the winter when DO concentration increased to normoxia, the pelagic larvae of benthic fauna settled in the soft sediments, but there was a spatial gradient in values of total biomass, density, and H' and benthic pollution index (BPI): higher values were found toward the mouth of the bay. The multivariate analyses like the cluster analysis and MDS ordination showed that Masan Bay could be divided into two or four stational groups in winter and summer whether the hypoxia occurred or not. Group I consisted of sites at the inner bay and central area and Group II, sites at the bay mouth. In summer the inner bay area could be further divided into the shallow impoverished area and the deeper abiotic one.

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

• The Korean Journal of Malacology
• /
• v.22 no.1 s.35
• /
• pp.63-86
• /
• 2006

A list of species of bivalve mollusks, their local distributions and relative abundance in Yeongil Bay were analysed. Species richness ranging from 1 to 37 species was low (less than 10) in some stations at the entrance and in the central part of the bay. Fifteen species (Acila insignis, Nucula tenuis, Yoldia notabilis, Mytilus galloprovincialis, Arca boucardi, Axinopsida subquadrata, Felaniella usta, Mactra chinensis, Raeta pulchella, Nitidotellina hokkaidoensis, Theora fragilis, Alvenius ojianus, Callithaca adamsi, Ruditapes philippinarum and Laternula anatina) were most frequently encountered, and seven of them were most abundant numerically (per sample): Th. fragilis in the inner bay, A. insignis, N. tenuis, and A. ojianus in the outer bay, and C. adamsi, A. subquadrata, R. puichella in both parts. Local distributions of common species were described and presented in plotted data, and three distribution patterns were recognized. Biogeographical analysis shows that a majority of species (55%) belongs to the subtropical group, tropical-subtropical species (16%) play a relatively significant role, and the percentage of boreal (temperate) and boreal-arctic species is 18% which characterizes the whole fauna as subtropical. Zonal-biogeographical composition and number of species in families in Yeongil Bay are compared with those of some Japanese (Wakasa and Mutsu) and Russian (Peter the Great, Possjet and Amursky) bays of the East Sea. The absence of a number of typical warm-water embaymental mollusks in Yeongil Bay found in the north further East Sea and Japan, and the similar zonal-biogeographical structure of the inner and outer bay faunas are explained by active water exchange due to the openness of the bay, relatively low summer temperatures, and presence of upwelled cold waters.

• 한국해양학회지
• /
• v.18 no.2
• /
• pp.111-116
• /
• 1983

A semi-quantitative investigation on the subtidal macrobenthic community was carried out using dredge in Garolim Bay from February 1980 to June 1981.Of the 340 species of benthic fauna collected,the most dominant species with the numerical abundance of 12.3% was an ophiruroid,Ophiactis modesta which had a strong colony nature.Garolim Bay was also dominated by many suspension-feeders like Ophiactics modesta and Musculista senhousia. Due to hetergenorous sediments,Garolim Bay appeared to be rich and diverse in the faunal composition.Based on th topography of the bay and sediment types,the study area is easily divied into two zones;inner bay and outward bay area.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.05a
• /
• pp.117-122
• /
• 2004

This study investigates the spatial and temporal distribution characteristics and relationships among water quality parameters, which based on 6 years' data(from 1989 to 1994) measured at 16 stations on Jinhae Bay. The results of these analysis, monthly variations range between surface and bottom layer of water quality had a tendency to increase and decrease, and appeared to be at the maximum value in August. The relationships between concentration of COD ana nutrients(DIN and DIP), which obtained by correlation analysis of water quality, were shown $85\%$ and $74\%$, respectively. Using the cluster analysis to develop the division of the sea basin by the dendrogram, before and after dredging of Masan bay and operating a sewage disposal plant, the variation characteristics of water quality of Jinhae Bay were discussed. Through it, we can see the serious pollution of northen sea basin of Jinhae Bay(B2) although dredging Masan bay and operating the sewage disposal plant. As the results, it doesn't appear the improvement effect of water quality in spite of carrying out the effort of water quality improvement.