• The Korean Journal of Malacology
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• v.17 no.1
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• pp.57-61
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• 2001

The present study examines the potential involvement of Biomphalaria glabrata, a known molluscan intermediate host of Schistosoma mansoni, in the life cycle of Echinostoma cinetorchis, one of the echinostomes that are ubiquitous parasites of vertebrates and are of importance in human and veterinary medicine and wildlife diseases. Echinostomes can be maintained easily and inexpensively in the laboratory and provide good models for biological research ranging from the molecular to the organismal. In the present study, no echinostome cercariae were released from the B. glabrata experimentally infected with E. cinetorchis miracidia, whereas all the Biomphalaria snails infected with E. cinetorchis cercariae were found to be infected with the metacercariae. This is the first report that B. glabrata can experimentally serve as the second intermediate host of E. cinetorchis, and that it might be employed as one of the target molluscs for establishing a biological research model with E. cinetorchis in the laboratory.

• The Korean Journal of Ecology
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• v.25 no.1
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• pp.59-62
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• 2002

Dokdo, which is located in the middle of the East Sea, is a small island tilth a total area of 0.186 $\textrm{km}^2$. However, this small island, with its mild oceanic climate, has rich bio-resources and picturesque natural surroundings. Dokdo in the crystaline waters and In the central area of the deep sea is a treasury of algaes (sea oak, sea mustard, gulf weed, laver, agar-agar, etc.), molluscs (squid, ear shell, conch, etc.) and fishes (Alaska pollack, anchovy, saucy, herring, etc.). On the other hand, there are a lot of grasses and various kinds of grasses on the land of Dokdo. And a lot of back-tailed gulls (about 20,000 Individuals) live on this island. There have been disputes on the sovereignty over Dokdo between Korea and Japan. Japan has claimed sovereignty over Dokdo since Japan incorporated the island into Japanese territory in 1905 when it occupied the Korean Peninsula by force. Korea governed Dokdo not only before 1905 but also after its liberation in 1945. The Korean government, while heavily financing building facilities like pleas and quays, is endeavoring to preserve the natural surroundings of this island.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.9-16
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• 2007

Data obtained from field observation revealed that the degree of shell bioerosion of the scallop, Patinopecten (Mizuhopecten) yessoensis, by endolithic organisms significantly higher on the muddy sand than on the sand. At the area studied, the polychaete worm, Polydora brevipalpa (=Polydora ciliata brevipalpa, Polydora ciliata Okuda, Not Johnston, Polydora variegata), which is common symbiotic species for the scallop made 95-100% of total scallop shell bioerosion at the area studied. The muddy bottom sediments enriched by organic matter create favourable conditions for development of microphytobenthos and bacteria, which are predominantly consumed by P. brevipalpa. Linear regressions for the degree of shell bioerosion on the scallop shell height, total wet weight and adductor muscle wet weight revealed negative relationships between them for the scallops inhabiting both sand and muddy sand. The influence of polychaetes on scallops is complex. They may be food competitors. Polychaete can directly affect the host through their boreholes. Scallop expends energy for shell regeneration to prevent the polychaete penetration into its interior cavity. It was found that the degree of shell bioerosion increased considerably with scallop age.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.616-617
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• 2001

Chejudo, because of its location off the south coast of the Korean peninsula, has a varied marine mollusk fauna. As a preliminary step in an attempt to enumerate and study the mollusks of the island, a field trip was made by the authors to the Songsan Ilchulbang area on february 20, 2001. The purpose of the trip was to survey the mollusk fauna of the shoreline west of Songsan. (omitted)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.175-187
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• 1997

Benthic community structure was studied in Chinhae Bay during 3 years from June 1987 to May 1990, based on the samples from 12 stations on the seasonal, bimonthly or monthly basis (lim and Hong, 1994a, b). A total of 287 species was sampled with mean density of $1045.5\;ind./m^2$ and biomass of $98.48g/m^2$ during studyperiods. Of these species, there were 91 species of crustaceans $(31.7\%)$, 88 of polychaetes $(30.7\%)$, 56 of molluscs $(19.5\%)$, 22 of echinoderms and 30 of the micellaneous species. Polychaetes were density-dominant faunal group with a density of $824.7\;ind./m^2$, comprising of $18.6\%$ of the total density of the benthic animals. It was followed by molluscs with $14.62\;ind./m^2$ $($14.4\%\;of\;the\;total\;density)$ crustaceans with $50.5\;ind/m^2\;(4.6\%)$ and echinoderms with $13.4\;ind/m^2\;(4.6\%)$. Molluscs were the biomass-dominant faunal group with a mean biomass of $54.62\;g/m^2$. It was followed by polychaetes with $21.74\;g/m^2$ and echinoderms with $6.66\;g/m^2$. Based on community analysis, species richness, diversity and evenness showed decreasing trends toward the inner bay from outer stations, whereas dominance showed increasing. The three most dominant species Lumbrineris longifolia, Paraprionospio pinnata and Theora fragilis had densities over $40\%$ of the total density of benthic organisms in Chinhae Bay. Seasonal changes of benthic communities in the inner bay were high compared to those of the outer bay. It was mainly due to the occurrence of hypoxic condition in the inner area of the bay. Cluster analysis showed that the benthic community could be divided into four stational groups, that is, Group 1, the innermost area, which received the most heavy anthropogenic effects including seawage and waste water, Group II, the central area of the bay, Group III, the transitional area, Group IV, the mouth pan of the bay exposed to the open sea. The areal groups based on the environmental factors coincided with the zonal groups from the species composition. This fact suggests that the overall spatial distribution of macrobenthos in Chinhae Bay was controlled by the sediment organic carbon content of the bay.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.327-339
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• 2001

Community structure of macrobenthos was studied at forty one stations of Hampyung Bay, southwest coast of Korea. Three replicate sediment samples were taken at each station in October 1997, using a van Veen grab (surface area $0.1\;m^2$). The types of surface sediment in the sampling area were muddy sandy gravel between bay mouth and bay proper, and gravelly sandy mud between bay proper and inner bay stations. The particulate organic carbon content in the surface sediment was $0.23\sim0.69\%\;(0.44\pm0.10\%)$. A total of 168 species collected during the study period is composed of 58 of polychaetes, 54 of crustaceans, 34 of molluscs and 22 of miscellaneous. The former two taxa together were accounted for $66.6\%$ of the total number of species. The mean density was $1,168 ind./m^2$, comprising $684 ind./m^2$of molluscs ($58.6\%$), $381 ind./m^2$of polychaetes ($32.6\%$), and $90 ind./m^2$of crustaceans ($13.2\%$). The mean biomass was $358.65 g/m^2$, which is consisted of $302.97 g/m^2$of molluscs ($84.5\%$), $24.20 g/m^2$of echinoderms ($6.7\%$), and $19.16 g/m^2$of crustaceans ($5.4\%$). Major dominant species at the inner stations of the study area was Ruditapes philippinarum with a density of $520ind./m^2$($44.5\%$), and Lumbrineris lontifolia with $183ind./m^2$($15.7\%$), while that at bay mouth stations Pitar indecoroides with $56ind./m^2$. Reticunassa festiva, Heteromastus sp., Praxillella affinis, Chone sp. and Tharyx sp. were at from all stations. Based on the cluster analysis, the macrobenthic community in the bay was classified into five station groups depending on sediment types: Group A, a high gravel content in the sediment; Group B, stations with high mud content from bay mouth to bay proper, Group C, stations with fine and poorly sorted sediment from bay proper to the inner bay. The distribution pattern of the number of species, abundance and biomass is discussed in relation to environmental variables.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.493-501
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• 2001

A study on the community structure of macrobenthos was accomplished around Kadugdo, a south coast of Korea. Sampling was performed bimonthly using a Smith-McIntyre grab ($0.05 m^2$) at ten stations from January to November, 1998. A total of 260 species was sampled with mean density of $1,729 ind./m^2$and biomass of $154.7 gwwt./m^2$during the study periods. Of these species, there were 96 species of arthropods ($37.0\%$), 89 species of annelids ($34.2\%$), 45 species of molluscs ($17.3\%$) and 30 species of others ($11.5\%$). Annelids were density-dominant faunal group with a mean density of $1,263 ind./m^2$which occupied $73.0\%$ of the total individual of benthic animals. Molluscs were represented as biomass-dominant faunal group with a mean biomass of $99.5 gwwt./m^2$ ($64.3\%$ of total biomass). The density-dominant species were a bivalvia Theora fragilis ($194 ind./m^2$) and five species of polychaetes, Lumbrineris longifolia ($177 ind./m^2$), Chaetozone setosa ($150 ind./m^2$), Sternaspis scutata ($116 ind./m^2$), Sigambra tentaculata ($106 ind./m^2$) and Hemipodus yenourensis ($94 ind./m^2$). And major biomass-dominant species was a bivalvia Ruditapes philippinarum ($45.6 gwwt./m^2$). Clustering analysis showed that the study area could be divided into two station groups and three stations: southwestern part of Kadugdo effected on Chinhae Bay, fisheries farming area and eastern part of Kadugdo effected on Nakdong River estuary.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.572-580
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• 2000

Community structure of macrobenthos was studied in Chinhae Bay, a southern coastal area of Korea. Sampling was conducted bimonthly using a Smith-McIntyre grab ($0.05 m^2$) at eight stations from January to November, 1998. A total of 237 species were sampled. It was comprised of annelids ($80 spp. 33.8{\%}$), arthropods (80 spp.), molluscs (47 spp.), echinoderms (16 spp,) and others, Mean density of individual was $1,939 ind./m^2$ and mean biomass was $171.6 gwwt/m^2$. Annelids were a density-dominant faunal group with a mean density of $1,533 ind./m^2$ which occupied $79.0{\%}$ of the total individual of benthic animals. Molluscs were represented as a biomass-dominant group with a mean biomass of $95.9 gwwt/m^2$ ($55.9{\%}$ of total biomass). The major density-dominant species were a bivalve Theora fratilis ($110 ind./m^2$) and five species of polychaetes, Lumbrineris longifolia ($417 ind./m^2$), Chaetozone setosa ($145 ind./m^2$), Sigambra tentaculata ($128 ind./m^2$), Cirratulus cirratus ($128 ind./m^2$), and Paraprionospio pinnata ($103 ind./m^2$). Cluster analysis showed that the study area could be divided into two station groups and two stations. According to the feeding guild of polychaetes, four feeding guilds were found, and the major ones were surface deposit-feeders, burrowing deposit-feeders, surface suspension-feeders, carnivore.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.413-422
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• 1997

To know the food chain of an intertidal community, feeding habits of Acanthogobius elongata were studied by analyzing stomach contents. A. elongata were monthly collected and the environment conditions of the habitat were investigated in the intertidal zone of Naecho-do, Kunsan from July 1993 to June 1994. Ratio of stomach contents to weight of A. elongata was $1.78\%$, and fullness of stomach showed a similar value to ratio of stomach contents to weight. Fullness of stomach was increased twice a day in the morning and the afternoon. The most important food item was copepods amounting to $54\%$ of the total stomach contents. Of these, Paracalanus parvus was most abundant in spring, Calanus sinicus in summer, Acartia sp. in autumn, and Calanus sinicus in winter. Degree of overlapping for the food items between seasons was not very high, except between spring and summer. There were little differences in feeding habits among the size groups. For all size groups of A. elongata, the occurrence rates of copepods, decapods, molluscs and cirriped larvae were high. As the fish grows, those of amphipods, polychaete larvae, isopods, cumaceans and stomatopods increased gradually. The importance index of the major food items was in the order of Calanus sinicus, Corycaeus affinis and Acartia sp..

• Journal of Marine Life Science
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• v.1 no.1
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• pp.31-40
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• 2016

Macrofauna and community structure were investigated seasonally at five sites in subtidal zone of Uljin on the east coast of Korea from March 2010 to February 2013. A total of 146 species were collected and identified, including 67 molluscs, 27 arthropods, and 8,688 individuals, including 6,468 arthropods, 1,098 molluscs and 584 echinoderms. In the seasonal investigation, summer has been the highest in 96 species and 2,525 number of individuals. Site 4 was the highest species but number of individuals were the lowest (81 species with 1,377 number of individuals), whereas site 3 was the lowest species and number of individuals were the highest (45 Species with 2,213 number of individuals). These result indicate that Balanus species affected to richness and the other side a gastropod influence by diversity and evenness. And site 3 seems to be good habitate environment for Balanus as the result of 83.4% of Balanus rather than other sites.