• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.2
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• pp.51-59
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• 2002

The seasonal variation in species composition and abundance distribution of zooplankton was studied in the Seomjin river estuary along the salinity gradients. In this estuary, marine taxa predominated in all seasons and very limited number of freshwater species appeared. The total abundances showed a seasonal fluctuation. The highest total abundance appeared in spring with over 3,000 individuals/m$^3$. In summer, the high abundance was sustained although it decreased a little. The abundance was minimal in fall with about 500 individuals/m$^3$. When the study area was divided into three salinity regimes, oligohaline (salinity less than 5 psu), mesohaline (5${\sim}$18 psu), and polyhaline zone (over 18 psu), the zone of high abundance as well as the composition of zooplankton community in each salinity regime changed seasonally. In fall, marine copepods predominated in oligohaline zone while marine species other than crustaceans dominated in polyhaline zone. However, in winter copepods predominated in all area. In spring and summer, holozoic dinoflagellate Noctiluca scintillans dominated in higher salinity regimes. We listed major copepod species of each salinity regime for each season with the ranges of water temperatures (T) and salinities (S) of their occurrence. T, S's of maximum abundances of those major copepod species were also reported. The observed very wide tolerance ranges of major copepod species for salinity suggested that the concept of 'indicator species' should be used in quantitative context rather than qualitative.

• Journal of Marine Life Science
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• v.1 no.2
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• pp.95-108
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• 2016

This study was performed to investigate the community structure of macrobenthic assemblages in the Environmental Conservation area, Korea. Benthic animals were collected by van Veen grab sampler at spring (May) and summer (August) 2009. The total species number and mean density were 195 species 5.6 m^-2 and 667 individuals m^-2, respectively. Polychaetes were the most dominant faunal group in species (96 species) and abundance (431 individuals m^-2). The major dominant species were the polychaetes Lumbrineris longifolia (76±224 individuals m^-2), Mediomastus californiensis (42±117 individuals m^-2), Tharyx sp.3 (26±110 individuals m^-2), the bivalvia Theora fragilis (54±78 individuals m^-2) and the amphipod Eriopisella schellensis (70±146 individuals m^-2). Based on the cluster and nMDS ordination analysis, macrobenthic communities were divided into three faunal groups. The first group was characterized by high abundance of the polychaeta Sternaspis scutata and the amphipod Ampelisca cyclops iyoensis, which is located by most stations of Hampyeong Bay and St. 4 of Deungnyang Bay. The second group was numerically dominated by the polychaeta Capitella capitata at St. 4 and St. 5 in Gamak Bay where was most pollutant area. Finally, the third group was dominated by the polychaetes Heteromastus filiformis, Tharyx sp.3 and the amphipod Sinocorophium sinensis. Therefore, geochemical characteristics such as the bay shape and pollution gradient may be important factors controlling of the macrobenthic community structure in Environment Conservation Area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.161-174
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• 1997

A study on the distribution of the major domiant species of macrobenthos was carried out in Chinhae Bay from lune 1987 to May 1990. The 13 dominant species, based on the number of individuals and frequency, occupied more than $70\%$ of the total individuals. Of these species, 11 species represented polychaetes $(85\%)$ and 2 species molluscs $(15\%)$. The dominant species included Lumbrineris longifolia, Paraprionospio pinnata and Theora fragilis, with a density of $173.3({\pm}55.4),\;169.3({\pm}257.8)\;and\;81.8({\pm}93.3)\;ind./m^2$, respectively. In terms of biomass these dominant species occupied move than $75\%$ of the total biomass of the macrobenthos. These were composed of 6 species of polychaetes, 7 of molluscs and one echinoderm. The biomass of Macoma tokyoensis, Periglypta cf. puerpera and Paraprionospio pinnata were predominant (more than $45\%$ of the total biomass), and their biomass were $14.69({\pm}30.17),\;8.71({\pm}29.40),\;4.17({\pm}11.93)g/m^2$, respectively. In terms of density, distribution patterns of Lumbrineris iongifolia, Paraprionospio pinnata, Aricidea jeffreysii, Magelona japonica, Sigambra tentaculata, Raetellops pulchella, Glycinde gurjanovae were discussed. In the inner area of the bay with high organic content, Lumbrineris longifolia, Paraprionospio pinnata, Aricides jeffreysii, Sigambra tentaculata, Raetellops pulchella were pvedominant, whereas in the mouth of the bay with low organic content, Magelona japonica, Glycinde gurjanovae, Sternaspis scutata, Theora fragilis were dominant. Lumbrineris longifolia was widly distributed throughout the bay. However, Paraprionospio pinnata, Aricidea jeffreysii and Sigambra tentaculata had high density particularly in the central pan of the bay where there was high organic content in surface sediment, and these species possibly can be used as the potential pollution indicating species.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.124-133
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• 2009

The study was performed to investigate the community structure of macrobenthic fauna during June 2005, in Hallyeohaesang National Park from Korea Strait. A total of 284 macrobenthic fauna were collected. The overall average macrobenthic density and biomass were 2,002 individuals m$^{-2}$ and 154.92 gWWt m$^{-2}$, respectively. Based on the Lebris (1988) index, there were 20 species accounting for approximately 47.64% of total individuals. And the highest densities were found in the polychaetes Scoletoma longifolia, Isolda pulchella, Mediomastus californiensis, Minuspio multibranchia, Tharyx sp. 1 and the bivalve Theora fragilis. On the other hand, the top twenty species made up 70.47% of the total biomass while the three most abundant, the echinoderms Schizaster lacunosus, Amphiura vadicola and the bivalve Fulvia mutica. The conventional multivariate statistics (cluster analysis and non-metric Multi-Dimensional Scaling) applied to assess spatial variation in macrobenthic assemblages. As a result of cluster analysis and nMDS ordination, this study area was divided into two different groups of stations and species. In case of station, there are two groups: one is a mud dominated station group and the other is dead shell and sand dominated group. And the 2 faunistic groups were established as follows: 1) a group of relatively higher abundances in mud dominated sediment. There were numerically dominated by the polychaetes Magelona japonica, Sternaspis scutata, Paraprionospio pinnata, Tharyx sp. 1 and the amphipods Monocorophium sinense and Eriopisella sechellensis. 2) a group of relatively higher densities dead shell and sand dominated sediment. These groups were characterized by the polychaetes I. pulchella, M. multibranchiata, the amphipods M. acherusicum, Gammaropsis japonicus and the echinoderm A. vadicola.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.6-19
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• 2009

We investigated the macrozoobenthos at major two harbors of Korea in July and August 2007 in order to check the changes in the species composition due to the invasive species and to make a species inventory at each harbor system. At the Incheon Harbor, a total of 88 species was sampled with abundance of 3,212 ind. m$^{-2}$ and biomass of 239 g m$^{-2}$. The most dominant species was Tharyx sp. belong to polychaete taxa, followed by Chaetozone setosa in the harbor area. The dominant species of outer area were Musculus senhousia and Sternaspis scutata. The diversity index ranged between 0.9$\sim$2.4, and evenness index between 0.3$\sim$0.9, and richness index between 1.8$\sim$3.9. Benthic pollution index ranged between 16$\sim$74. The highest benthic pollution index was at station 4. On the other hand the lowest value was at station 6, where a large amount of M. senhousia belong to mollusca occurred. At the Busan Harbor, a total of 89 species was sampled with density of 1,845 ind. m$^{-2}$ and biomass of 133.6 g m$^{-2}$ in August 2007. The most dominant species was Tharyx sp., followed by M. japonica and Cirratulus cirrata within harbor area. M. japonica was dominant species in the outer area. The diversity index ranged between 0.7$\sim$2.2, evenness index between 0.3$\sim$1.0, and richness index between 1.1$\sim$4.1. Benthic pollution index ranged between 31$\sim$90. The lowest benthic pollution index was found at site 2 within harbor area.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.3
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• pp.100-117
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• 2022

This study examines the spatio-temporal characteristics of the macrobenthic community in the coastal areas of South Korea for the past six years(2015-2020). The relationship between the number of individuals of macrobenthic species and the benthic environments were investigated using data collected at a total of 154 stations located in the West (70), the South (61), and the East Seas (23), except for the Jeju Sea. We examined the benthic environmental characteristics such as water depth, sediment, grain size, ignition loss, and total organic carbon. A total of 1,614 macrobenthic species were found in the coastal area, with a mean density of 0.62 ind./m² by station. The mean density was relatively high in the spring and summer seasons (May to August) with more than 450 species. The most dominant species belong to Polychaetes and the top five of them accounted for more than 20% of the total number of populations. The top five species were Heteromastus filiformis, Scoletoma longifolia, Sigambra tentaculata, Sternaspis scutata, and Notomastus latericeus. Cluster analysis was performed on the top five dominant species. The stations were clustered into three groups with similar locations on the West, South, and East Sea. Cluster 1 and 3 represent Heteromastus filiformis (44% each), but cluster 2 represents Scoletoma longifolia (66%). Each cluster has different benthic environmental characteristics, especially in the sediment's sand (31.0%, 51.9%) and clay (15.9%, 9.7%) contents.