• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.76-86
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• 2012

Macrozoobenthos were collected from 24 sites using small grab ($0.05m^2$) in order to see the spatial distribution of them at Sueocheon stream at the northern part of Gwangyang Bay during summer season when the maximum ecological processes are occurring. A total of 44 species of macrozoobenthos occurred, and their mean density was $789individuals/m^2$. Mollusks was the dominant faunal group accounted for 43.1% and 86.8% of the whole community density and biomass, respectively. Top five dominant species were a molluscan, Corbicula japonica (40.7%), two polychaete worms, Neanthes japonica (19.3%) and Heteromastus filiformis( 8.1%), and two crustaceans, Paranthura japonica (6.9%) and Jaeropsis sp. (6.9%). Species diversity index was very low with mean value of 1.12 and maximum value was recorded at the river mouth. At the upper stream, a brackish water species such as Corbicula japonica showed their maximum population density. The overall distribution of stream macrobenthos showed a rather simple pattern along with salinity and grain size gradients with few brackish water species occurring at coarse sediments in the stream but more diverse faunas inhabiting fine sediments in the river mouth.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.214-227
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• 1998

This study was carried out to investigate the composition and diagenesis of the carbonate rocks from the seamounts in the Federated States of Micronesia, Central Pacific. Most of the samples were dredged from the water depth of about 1000-3000 m mainly in Chuuk Island, Hunter Bank, Caroline Ridge and Yap Trench. The carbonate rocks are either pelagic sediment mainly of planktonic foraminifera or shallow-marine sediment of corals, calcareous algae, mollusks and echinoderms. The rocks are altered texturally and chemically, except for those from the Hunter Bank and Yap A. The presence of shallow-marine cements suggests that the carbonate sediment has been subsided or reworked to the present water depth after deposition in shallow-marine environments. The texture of the carbonate sediment is reminiscent of meteoric diagenesis; however, the stable carbon isotopic composition of the altered rock samples shows affinity with that of sea water and the oxygen isotopic values are slightly enriched or same as compared to those of unaltered samples. These stable isotopic data suggest that the carbonate sediment of the study area has been diagenetically altered in the present deep-marine environment.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.80-92
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• 1999

This study was conducted to describe the community structure of macrobenthos in Aenggang Bay, the southern coast of Korea. Sampling was performed seasonally using van Veen grab from October 1994 to August 1995. A total of 233 species occurred; polychaetes accounted for 90 species, crustaceans 66 species, and mollusks 46 species. The mean density of macrobenthos was 1,358 ind./$m^2$, and polychaetes accounted for 64% of total abundance with its density of 874 ind./$m^2$. Mean macrobenthic biomass was 261.96 gWWt/$m^2$, and echinoderms accounted for 52.6% of total biomass with its biomass of 137.76 gWWt/$m^2$. Dominant species were a serpulid worm, Ditrupa arientina (245 ind./$m^2$), a cirratulid worm, Tharyx sp. (166 ind./$m^2$), and a scaphopod Fustaria nipponica (132 ind./$m^2$). Ditrupa arientina and Fustaria nipponica were distributed mainly in the mouth of Aenggang Bay, whereas Tharyx sp. showed its high density in the central region of the bay. The study area showed a regional difference in species richness, abundance, and biomass; the eastern region of the bay sustained relatively more abundant and richer macrobenthos than the western part. The study area could be divided into 5 regions by the cluster analysis based on the species composition of macrobenthos; the inner bay, two central regions, and two mouth areas of the bay.

• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.238-249
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• 2005

The present study was carried out to apprehend that the pollutants originating from Jinhae Industrial Complex affect benthic polychaetous community in the northern Jinhae bay. An investigation on the macrobenthic community in Jinhae bay was conducted in September, December of 2002 and March of 2003. The benthic fauna showed mean density of 2,151 ind. $m^{-2}$ in September of 2002, 2,427 ind. $m^{-2}$ in December of 2002 and 2,394 ind. $m^{-2}$ in March of 2003. Major faunal groups are polychaetes, crustaceans and mollusks, corresponding to $73.7\%,\;12.0\%\;and\;11.7\%,$ in total mean density during all of the sampling season, respectively. The most abundant species was Lumbrineris longifolia $(24.85\%),$ followed by Tharyx sp. $(21.70\%),$ Mesochaetopterus sp. $(6.20\%),$ Heteromastus filiformis $(5.39\%),$ Prionospio sp. $(5.18\%),$ Clycinde sp. $(4.29\%),$ etc. Tharyx sp. was the highest abundant species in September of 2002, and Lumbrineris longifolia was the dominant species in another sampling seasons. The density and the species number of polychaetes were high around Chori Is. and poor near Jinhae Industrial Complex area. Cluster analysis based on the species composition showed that Jinhae bay could be divided into three regions except in March of 2003. In December of 2002, there are very distinct regions by the cluster analysis. The density of benthic polychaetes in Jinhae bay was higher than that in the other coastal area of Korea, due to the predominance by some of opportunistic species, such as Lumbrineris longifolia, Tharyx sp. and Heteromastus filiformis, etc. It means that the study area were in the process of organic enrichment.

• Journal of Life Science
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• v.26 no.10
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• pp.1218-1223
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• 2016

Abalones are gastropod mollusks belonging to the genus Haliotis. Fishery products are continuously declining worldwide while abalone production from aquatic farms has considerably increased. Although abalones are regarded as very important marine resources and considered to have big potential in sea-food farming industry around world, the slow growth rate of Pacific abalones is considered to be one of the most serious problems. For the genetic improvements in cultured abalone, advances in various breeding techniques for abalone have been reached through the introduction of selection, crossbreeding, hybridization, and polyploidy in several commercially important abalone species. Six species of abalone have been reported to be distributed along the coasts of Korea: Haliotis discus hannai, Haliotis discus discus, Haliotis madaka, Haliotis gigantea, Haliotis diversicolor diversicolor, and Haliotis diversicolor supertexta. The hybridization between these abalones may be one of the advanced technologies, and the preliminary experiments of interspecific hybrids between abalone species distributed in northern pacific areas including Korea, China, and Japan have been conducted. In this study, we reviewed the phylogenetic relationship of northern pacific abalone species which have the potential traits for aquaculture in Korea and their identifications. We also examined the development of molecular markers and some other aspects of the genetic approaches for successful development of hybrids.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.225-237
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• 2001

The community structure of macrobenthos was investigated around Sorido Island, southern coast of Korea between August 1996 and April 1997. Triplicate macrobenthic samples were taken seasonally at twelve stations in August and November 1996 and fourteen stations in February and April 19n by van Veen grab ($0.1m^2$). A total of 217 macrobenthic species were identified during study Period: 80 species were from polychaetes, 60 species from crustaceans, and 46 species from mollusks. The mean density of macrobenthos estimated $1,068 ind/m^2$, and polychaetes comprised $85\%$ of total density. The mean biomass was $110.2 g/m^2$, and echinoderms contributed to more than a half of the biomass. Major dominant species based on abundance were three polychaetes Tharyx sp., Lumbrineris longifolia, and Magelona japonica, which frequently occur in the coastal area enriched by organic pollution. The densities of the species were $582 ind/m^2$, $72 ind/m^2$, and $41 ind/m^2$, respectively. These species showed very low density in the offshore area. The study area was classified into four regions each sustaining specific macrofaunal assemblages by Bray-Curtis cluster analysis: a station group adjacent to the Kwangyang Bay and Yosu harbour and three station groups around Sorido Island. There were negative correlations between the concentration of PAHs in sediments and the abundance of Ampeliscidae spp. and Amphipoda. These results were discussed in terms of both environmental factors and distribution of benthic community.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.245-252
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• 2016

Background: Ingestion of $^{210}Po$ laden seafood accounts for a substantial amount of the effective dose of $^{210}Po$. Among seafood items, mollusks, especially domestically produced oysters and mussels, are highly enriched in $^{210}Po$ and are consumed in large quantities in Korea. Materials and Methods: Oysters and mussels around the Korean coasts were collected from major farm areas in November 2013. Samples were spiked with an aliquot of $^{209}Po$ as a yield tracer, and they were digested with $6mol{\cdot}L^{-1}$ $HNO_3$ and $H_2O_2$. The $^{210}Po$ and $^{209}Po$ were spontaneously deposited onto a silver disc in an acidic solution of $0.5mol{\cdot}L^{-1}$ HCl and measured using an alpha spectrometer. The activity concentrations of $^{210}Pb$ and $^{210}Po$ were decay corrected to the sampling date, accounting for the possible in-growth and decay of $^{210}Po$. Results and Discussion: $^{210}Po$ activity concentrations in oysters were in a range from 41.3 to $206Bq{\cdot}(kg-ww)^{-1}$ and mussels in a range from 42.9 to $46.7Bq{\cdot}(kg-ww)^{-1}$. The $^{210}Po$ activity concentration of oysters in the turbid Western coast was higher than the Southern coast. The $^{210}Po$ activity concentration of the oysters was positively correlated ($R^2=0.89$) with those of the suspended particulate matter in the surface water. The calculated annual effective dose of $^{210}Po$ from oysters and mussels consumed by the Korean population was 21-104 and $5.01-5.46{\mu}Sv{\cdot}y^{-1}$. The combined effective dose due to the consumption of oysters and mussels appears to account for about $35{\pm}19%$ of that arising from seafood consumption in the Korean population. Conclusion: The annual effective dose of $^{210}Po$ for oysters in the Korean population was found to be higher than other countries. The total annual effective dose of $^{210}Po$ due to consumption of oysters and mussels consumed in Korea was found to be $76{\pm}42{\mu}Sv{\cdot}y^{-1}$, accounting for $28{\pm}16%$ of the total effective dose of $^{210}Po$ from food in Korea.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.65-71
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• 2012

Protozoan parasites belonging to the genus Perkinsus elicit severe inflammatory responses and are associated with mass mortality of commercially important marine shellfish worldwide. In the present study, we examined the external features of P. olseni zoospores in detail using light and scanning electron microscopy. Our study showed that the zoospores have an oval body with a long anterior flagellum and a short posterior flagellum. The anterior flagellum has a unilateral array of mastigonemes. Mean body dimensions were $3.37{\pm}0.33{\mu}m{\times}1.72{\pm}0.22{\mu}m$. The average length of the anterior and posterior flagella was $16.34{\pm}1.52{\mu}m$ and $8.25{\pm}1.39{\mu}m$, respectively. Zoospores of P. olseni found in Korean waters have shorter and narrower bodies, longer anterior flagella, and shorter posterior flagella than zoospores of Perkinsus spp. found in the mollusks of North America and Europe.

• Journal of fish pathology
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• v.26 no.3
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• pp.193-206
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• 2013

The ark shell, Scapharca broughtonii is a marine bivalve mollusks belonging to the family Arcidae and important seafood for Korean and Japanese, and southern coast is brisk bays for the ark shell aquaculture. However, productivity of ark shell from these regions were rapidly reduced during the last decade due to mass mortality. The reason of this great damage has not yet been identified. To overcome this economic loss, diverse investigations were focused on environmental factors that affects in the physiology of S. broughtonii, but microbiological researches were performed insufficiently. Hemoglobin is one of the major blood component of ark shell and is damaged by some species of bacterial toxins. We concentrated on this red pigment because hemolysis could be the cause of ark shell mortality. In this study, we analyzed microbial diversity of underwater sediments in coastal regions and also existences in the body of S. broughtonii. We investigate about 4,200 isolates collected from June to September for microbial diversity of sediments and ark shell. We screened all of culturable microorganisms, and identified 25 genera 118 species, 24 genera 89 species, 30 genera 109 species and 39 genera 141 species, and selected 140 unique colonies for identification and challenge assay.

• Animal Systematics, Evolution and Diversity
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• no.nspc5
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• pp.29-46
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• 2005

As a commemorative joint survey for the 20th anniversary of the Korean Society of Systematic Zoology, molluscan fauna of Jindo Island was investigated from the materials collected from 3 localities of Jindo Island from 29th to 30th of June, 2004. A total of 77 species of 37 families were identified. Among them, 26 species of 18 families are reported for the first time in this area, including Onchidella kurodai (Taki, 1935) that is new to Korean fauna. For O. kurodai, external morphologies were described in detail with illustrations. Combining the present data with those of the previous works revealed that a total of 115 species from 43 families have been recorded in Jindo Island and its adjacent areas thus far. From a biogeographic point of view, some gastropod species (Bittium craticulatum, Mocroschisma dilatatum, Cantharidus japonicus, C. callichroa, Homalopoma sangarense, and Crepidula onyx) encountered from Jindo Island were the species previously recorded in the southern and/or eastern offshores of Korean peninsula, including Jeju Island (Choe, 1992). Along with the fact that Jindo Island contains a large number of molluscan species ranging over the Yellow Sea coast, this finding is another line of evidence supporting the Kim and Kwon (1983)'s idea that this area is an overtopping zone of marine organisms which dwell in both the Yellow sea and southern part of Korean sea waters. No comprehensive faunistic survey was not made in the present study. We expect that further supplementary study would generate more biogeographic and faunistic knowledges than what we understand through the present study.