• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.1 no.2
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• pp.73-79
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• 1996

This study was conducted to investigate the faunal composition and distribution patterns of macrobenthic community in the deep sea sediments of the KODOS area, the northeastern Pacific Ocean during May 1996. Benthic animals were collected at 25 stations using a spade type box corer. Sediments were sieved through -.3 mm mesh screen. A total of 17 faunal groups in 9 phyla and 363 specimens were identified. Nematoda was the most abundant faunal group which accounted for 30.0% of total abundance. Other dominant faunal groups were foraminiferans (25.1%), harpacticoids (10.2%), xenophyophores (5.2%), and polychaetes (4.7%), Polychaeta was a typically dominant component of macrobenthic community in the study area except traditionally recognized meiofauna taxa. Mean occurrence number of faunal taxa was ca. 6 per 0.01 m$\^$2/, and mean density was estimated as 1,288 indiv./m$\^$2/. The abundance of whole fauna and that of each faunal group was highest at the surface layer of sediment, and decreased monotonously along the sediment depth; 98% of faunal abundance was found within 10 cm depth layer.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.43-55
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• 2004

Meiobenthic community structure was studied in intertidal mud flat and sand flat of Yeochari in Ganghwado in May and August, 1998. Sixteen groups of meiofauna were found at all study sites in the Yeochari tidal flats. Nematodes were the most dominant animal group among the meiofaunal groups as a whole. Sarcomastigophorans, harpacticoid copepods, nauplius larvae of crustaceans and ciliophorans which were also important components of the meiofaunal community. All of these five faunal groups comprised more than 90% of total meiofauna. The maximum total density of meiobenthos was $5.8{\times}10^6ind./m^2$ at the station of sand flat in August and the minimum density was $4.0{\times}10^6ind./m^2$ at same station in May. Biomass of meiobenthos was $1.5g/m^2$(May), $2.3g/m^2$(August) at mud flat and $1.7g/m^2$(May), $2.6g/m^2$(August) at sand flat. At the station of mud flat in May, the highest density was observed within 1cm in depth of upper sediment and steeply decreased increasing depth of sediment. At the sand flat station in August, the highest density was also observed within 1cm in depth of upper sediment and decreased with depth, while the concentration of the animals at the surface was not conspicuous as the mud flat. The value of N/C(nematodes/benthic harpacticoids) ratio was the highest at the station of sand flat in May and the lowest at the sand flat in August.

• Korean Journal of Environmental Biology
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• v.19 no.2
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• pp.159-171
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• 2001

Community structure, horizontal distribution, density, and ratio between nematodes and benthic harpacticoid copepods of the meiobenthos within the sediments of inner Sihwa Lake were investigated in May 1999 and May 2000. A total of 11 and 8 classes of meiobenthic animals were identified in 1999 and 2000, respectively, which were much lower than other coastal areas. The dominant animals during both sampling periods was the nematodes, followed by sarco-mastigophorans, nauplius of crustaceans, benthic harpacticoid copepods and polychaetes. These five classes of animals comprised more than 90% of total abundance of neiobenthos presented in the samples. In 2000, a lot of polychaete larvae were identified. The most abundant animal were the size that fits in 0.063 mm sieve size. Lower density was observed upper inner part of the Sihwa Lake during both sampling periods, and higher density was observed around the Sihwa floodgates. The average density between those two numbers were observed in the samples collected in the middle of the lake. Lower nematodes to betnhic harpacticoides (N/C) ratio, a relative indicator of environmental pollution, was observed to be lower around the floodgate but higher ratios were observed in the upper inner Sihwa Lake. The present study indicated that inner upper part of the lake becomes unsuitable for the meiobenthos, and the most inner upper lake was considered to be polluted.

• Ocean and Polar Research
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• v.27 no.3
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• pp.299-309
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• 2005

The community structure of meiobenthos was studied in the sediment of Kongfjorden, Spitsbergen of Svalbard Island in the Arctic Sea. Samples of meiobenthos were collected in August, 2003. Meiobenthic organisms were collected by SCUBA and van veen grab or acryl sub-corers 34mm in internal diameter, and were taken from upper sediment to a depth of 3cm at each station. A total of 26 meiofaunal groups were found in the sediment of Spitsbergen in Svalbard Island. Nematodes were the most dominant faunal group. Sarcomastigophorans, benthic harpacticoids, and nauplius larvae of crustaceans, were also important components of the meiobenthic community of Kongsfjorden. All of these low faunal groups were comprised of more than 90% of total meiobenthos at every station. The total density of meiobenthos at each station was highest at station MeG 6 $(3,583{\pm}1,137inds./10cm^2)$, and lowest at station $MeG9(28{\pm}1inds./10cm^2)$. Meiobenthos in general showed the highest density in the upper 1cm layer. This may be associated with food and oxygen supply to subsurface. Harpacticoids showed extreme preference at the surface and little presence in layers deeper than 2cm. These animals may be less resistant to oxygen deficiency, and nauplius also showed the same trend. However, in St. MeG 8 and 9, meiobenthos were dense at depths of more than 0-1cm, at especially at depths of 2-3m because of relatively easy penetration of oxygen. Based on the results of cluster analysis, three meiobenthos assemblages were distinguished: one was in the outer and two were in the inner fjord. Station SCU 5 was grouped with the meiobenthos assemblage located in the outer fjord. The outer ford community was characterised by : 1) a relatively low mean number of meiobenthos taxa, 2) a relatively high density of harpacticods and nauplius. One of the inner ford communities (a group of four nation: MeG 2, 3, 8, 9) was in the proximity of the glaciers. Specifically, it was characterised by : 1) a low mean number of meiobenthos taxa, 2) a low density. The other inner ford community was characterised by both a high density and great mean number of meiofaunal taxa.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.307-319
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• 2000

Community structure (seasonal fluctuation), taxon diversity, nematodes/benthic harpacticoids and nematodes/kinorhynchs ratios of meiobenthos were studied in the Gamak Bay, Korea. A series of samplings were carried out from April 1997 to May 1999. Meiobenthic organisms was collected by van Veen grab and three subcores of 34 mm in internal diameter were taken from each sediment sample. The total density of meiobenthos in each seasons was found to be the highest in May 1999, and the lowest in December 1998. Total density of meiobenthos at each station was the highest at Station 9 in May 1999 ($2,218 inds./10 cm^2$) and the lowest at Station 3 in December 1998 ($2 inds./10 cm^2$). The Gamak Bay seemed to have an individual number increased from the inner toward the outer stations. The highest number of meiobenthos was observed on 0.125 and 0.063 mm mesh size. In every season, over $80{\%}$ of the meiobenthos was composed of only four groups: nematodes, benthic harpacticoids, sarcomastigophorans and nauplius larvae of crustaceans. Seasonal fluctuation of meiobenthos was also studied. The nematodes/benthic harpacticoids(nematodes/kinorhynchs) ratios were studied as an index of pollution monitoring for benthic ecosystem at each station in each season. The value of nematodes/benthic harpacticoids ratio was the highest at the inner stations and the lowest at the outer stations in the Gamak Bay. Taxon diversity (H') was the highest at the outer stations and the lowest at the inner stations in the Gamak Bay. The value of nematodes/benthic harpacticoids ratio significantly increased from the outer toward the inner stations, whereas the taxon diversity (H') significantly increased from the inner toward the outer stations in Gamak Bay.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.279-290
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• 2000

To alleviate the harmful effects from contamination, the Sihwa Lake waters have been regularly fluxed out into the ocean to mix and circulate with the oceanic waters, and then allowed to flow back into the lake. In the present study, eco-environmental impacts by the outflowing contaminated lake waters to the benthic communities of the coastal zones along Kyonggi Bay were examined at three separate areas. A total of 22 groups of meiobenthic animals were commonly found in the subtidal zones of the Bay. All groups of the meiobenthic animals on the 1st and 7th days after the outflow were remarkably reduced in numbers from the selected areas examined, as compared to those observed one day before the outflow. It was also found that the community structure of meiobenthos was changed drastically: At the station near the water gate, for example, where the immediate outflow of the lake water was encountered, the benthic harpacticoids, the group observed to be one of the predominant groups before the outflow, were found to have disappeared completely. For an area that was relatively far away from the water gate, the reduction rate of meiobenthos after the outflow events was slower and more gradual than the nearer sites. An area that is the farthest from the water gate, no reduction in any of the meiobenthos group was observed. The ratio between nematodes/copepods (N/C) was remarkably changed by the outflows at the station near the water gate: One day before the outflow, the ratio was 0.7 while the ratio was 19.0 at the station near the water gate. In contrast, at the stations relatively far from the water gate, the ratio decreased one day after the outflow event, but increasing trends were observed one week later. In the tidal flats, Station 1 exhibited the common observed regional values of the ratio whereas Station 2 showed a very high ratio of 191.3. The results suggested that the contaminated lake water outflows directly effect meiobenthos in a relatively short time period and thus the meiobenthos may be a good indicator animal group for examining the effect of pollution. [Lake Sihwa, contaminat water outflow, meiobenthic animals living]

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.1
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• pp.1-13
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• 2003

To investigate the community structure and meiofaunal density in seagrass/bare non-seagrass beds, a survey was conducted at three seagrass bed locations in Doomoojin of Baegryongdo, inner harbor of Eocheongdo in May 1999, and Yulim of Dolsando for every month from February to July 1999. Meiobenthic samples were collected from sediments within seagrass beds (SB) and non-seagrass bed (or adjacent to barren sand area, NSB). Nematodes were the most dominant group among representative 13 meiofaunal groups. The sub-dominant groups were benthic for-aminiferans, benthic harpacticoids, and annelids. The highest density of meiofauna was recorded at a seagrass bed of Yulim (7,244 ind/10 $\textrm{cm}^2$ in June), and lowest density was recorded at a non-seauass bed of Baegryoungdo (438 ind/ 10 $\textrm{cm}^2$ in May). For vertical distribution, the highest density of meiofauna was recorded at 0-2 cm depth, and the density abruptly decreased with depth in all stations. The density of meiofauna in size between 0.125 m and 0.25 mm was maximum. Sediment types for the study areas ranged from sandy to sandy mud by the Folk's classification. The density of total meiofauna, the number of taxa, and the density of the dominant groups (nematodes, benthic for-aminiferans, benthic harpacticoids, annelids) between SB and NSB were significantly different. The results clearly showed the importance of seagrass bed as suitable habitat for meiofauna.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.4
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• pp.144-157
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• 2016

The community structure of meiobenthos was investigated from seasonal surveys at four stations of Keunso Bay in Taean. Samples of meiobenthos were collected in August, October, 2013 and January, April, 2014. Triplicate faunal samples were collected by using an acryl corer with a 3.6 cm diameter at each station. The mean grain size of the study area ranged from 3.65 ø to 6.35 ø. Total 13 meiofaunal groups were found in the study area. The total density of meiobenthos at each station was be $1,521-7,849ind./10cm^2$. Nematodes were the most dominant faunal group at all stations. The subdominant group were Sarcomastigophorans and benthic harpacticoid copepods. The highest meiofaunal density was shown in spring, whereas the lowest density was recorded in summer. A total of 13 meiobenthic taxa were found, the richest taxa in October at station 2 ($13ind./10cm^2$), and the lowest in April at station 4 ($5ind./10cm^2$). There were seasonal fluctuations in the number of meiobenthic taxa decreasing from summer to spring. The density of meiobenthos gradually decreased as the depth of sediment increased. Seasonal changes in the vertical distribution of meiobenthos in the study area occurred mainly near the sediment surface.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.308-320
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• 2004

The Community structure of meiobenthos was studied seasonally at 5 stations of Bangameori tidal flat and 3 stations of subtidal area in Daebudo near the Shiwha dike in the west coast of Korea, from May 2000 to February 2001. Mean grain size of intertidal stations ranged from $3.16\;\varphi\;to\;3.73\varphi$ (sand), subtidal stations were $5.81~6.67\;\varphi$ (mud). Nematodes were the most dominant group among the representative 19 meiofaunal groups at all stations in both tidal flat and sub-tidal area. The subdominant groups were benthic harpacticoid copepods and Sarcomastigophorans. The density of meiobenthos ranged from 145 inds. $10cm^{-2}$ to 2,057 inds. $10cm^{-2}$ (0~1 cm) in the sediment of intertidal stations, and from 391 to 3,787 inds. $10cm^{-2}$ (0~5 cm) in the subtidal stations. The lowest meiofaunal density was recorded in winter, whereas the highest density was shown in spring. Comparing with another previous work at the same area, data from this study does not statistically shown differences with results before discharge of shiwha lake water.

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.191-199
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• 2005

The community structure, vertical distribution and harpacticoids composition of the meiofauna community were observed from five stations in Marian Cove, King George Island and one station on the northeastern side of Nelson Island. Sample was taken by a free-fall corer in December 2002. Generally, 11 taxa of meiofauna were found, and meiofauna abundance ranged from 322 to 1575 indiv. $10cm^{-2}$ (mean 781 indiv. $10cm^{-2}$). Nematodes were the most dominant group, making up $89\%$ of total meiofauna, followed by harpacticoids $(6.8\%)$. Benthic harpacticoids appeared 19 species of nine families at all the stations, and most various taxa appeared at station B (13 species of seven families). For vertical distribution, more than $70\%$ of meiofauna was concentrated in the upper $0\~2cm$ sediment layers, and the density abruptly decreased with depth in all the stations. Total biomass of meiofauna varied between 41 and $360{\mu}gC\;10cm^{-2}$, and overall mean biomass was $205{\mu}gC\;10cm^{-2}$. Also nematodes had the highest percentage of total maiofauna biomass $(62.4\%)$. The analysis results of Canonical Correspondence Analysis between meiofauna community and sediment grain size showed that polychaets, oligochaets and cumaceans were influenced by silt&cray, and sand, granule and pebble had a influence on harpacticoids, kinorhynchs and ostracods respectively. But nematodes were not affected by sediment grain size.