• Journal of Environmental Science International
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• v.23 no.8
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• pp.1513-1522
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• 2014

Fish passage asssessments were conducted in the fishway at Juksan Weir, which was constructed as a four-major rivers project in the downstream area of Youngsan-River Watershed. For the research, fish-movements/migrations were analyzed for seven times from April ~ October, 2013 using an approach of fish trap-setting. Fish fauna and compositions were analyzed in the fishway, and seasonal- and diel-movement patterns were analyzed in relation to current velocity in the fishway. Also, abundances of exotic fishes such as bluegill sunfish (Lepomis macrochirus), large-mouth bass (Micropterus salmoides), and white curcian carp (Carassius cuvieri) were monitored in the fishway. Current velocity(n = 18) in the fishway showed large variations ($0.82{\pm}0.63m/s$) depending on the location of the fish trap-setting and this physical factor influenced the fish movements. Fish movements, based on the CPUE of individuals, in the fishway was greater in slower velocity (mean: 0.36 m/s, range: 0.10~1.54 m/s) than faster velocity (mean: 1.51 m/s, range: 0.90~1.90 m/s). Seasonal analysis of fish movements showed that most frequent uses (8 speices and 591 individuals, 66.2% of the total) of the fishway occurred in spring period(i.e., June). Diel movement analysis, in the mean time, showed highest in the time period of 00:00 ~ 3:00 am (7 species and 281 individuals, 20.9% of the total). The efficient managements in the fishway at Juksan Weir are required in relation to the hydrological regime.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.4
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• pp.346-356
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• 2000

This study was carried out to investigate the distribution pattern of macrobenthos in the subtidal sandy bottoms of the east coast of Korea, and seasonal samplings were performed from April 1993 to February 1994. The species number of macrobenthos was in the range from 70 in winter to 109 in spring season. Polychaete worms were the most dominant faunal group in species richness and abundance, but mollusks showed the highest biomass. The mean density of macrobenthos fluctuated from 631 individuals/m$^2$ in autumn to 1,995 individuals/m$^2$ in summer. The major macrofauna in abundance were polychaetes, Spiophanes bombyx which occurred all seasons with top rank and Prionospio sp. and a mollusk, Alvenius ojianus, and crustaceans, Wecomedon sp. and Urothoidae spp. were also numerically dominant macrobenthic fauna. The macrobenthos in the study area were classified into two assemblages by water depth. However, they showed a different community structure near small rivers in autumn and winter seasons.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.419-431
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• 2013

It was turned out by the beam trawl survey in 2009 that flora of three phylum 16 species and fauna of eight taxa 68 families 97 species were inhabited in the Seomjin River estuary and western coastal waters of Namhae island. Winter season showed the most various appearance of species with 63 species and markedly several kinds of algae species, while summer season showed the lowest number of species with 44 species. However, the indices of species diversity and evenness were highest in summer, and vice versa in winter. Major dominant species were Crangon hakodatei, Leiognathus nuchalis, Asterias amurensis, Thryssa kammalensis, Luidia quinaria, Amblychaeturichthys hexanema, Oratosquilla oratoria, Charybdis bimaculata, Cynoglossus joyneri, Pennahia agentata. The 10 dominant species occupied at 81.4% of catch in number and 49.0% of catch in weight. There were seasonal fluctuations and differences by station in the Seomjin River estuary and western coastal waters of Namhae island, which brought to the difference of length structures, that is, bigger-sized individuals of major dominant species at station A (near to river estuary) than station C (near to ocean). Species compositions by season and by station were separated to two groups. Winter season showed a separated species composition from other seasons and station A exhibited a different species composition from other stations, which was located at near to the Seomjin River estuary.

• Ocean and Polar Research
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• v.39 no.1
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• pp.23-34
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• 2017

This study was carried out to investigate the spatial distributions of the macrobenthic communities in the Seomjin River estuary from May, 2015 to May, 2016. The number of species was 163, the mean density was $1,865ind.m^{-2}$, biomass was $204g{\cdot}wet\;m^{-2}$ during this study period. The highest number of species and density appeared among polychaetes whereas the most biomass was contributed by mollusks due to the presence of Corbicula japonica in every season. The study area was divided into 3 regions with similar benthic fauna responding to the gradient of the salinity. Praxillella praetermissa was the dominant species in regions of over 30 psu during all seasons. C. japonica and Hediste diadroma were dominant in the upper regions of the Seomjin River where the salinity was less than 10 psu. Heteromastus filiformis showed the broadest distributional range and dominated in all seasons except for the most upper stream at st. 7. From the result of the Bio-Env analysis, salinity was the most important environmental factor affecting the formation of macrobenthic communities in the study area, and salinity and TOC were the highest contributors to the macrobenthic communities. From the correlation analysis between major dominant species and environmental factors, C. japonica, Prionospio japonica and H. diadroma showed a negative correlation with salinity, while P. praetermissa and Scolectoma longifolia showed a positive correlation. H. filiformis was little affected by salinity but showed a positive correlation with TOC or silt content of sediment.

• The Korean Journal of Quaternary Research
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• v.2 no.1
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• pp.51-85
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• 1988

The understanding of the faunal sequence and palaeoenvironment of East Asia since the Late Tertiary depends mainly on the knowledge of Chinese fauna and its environmental changes. The recent Chinese researches including geology, geomorphology, climats fluctuation and loess distribution of this area have provided that the rapid uplifting of Himalayas and Qinghai/Xizang Plateau since the Lower Pleistocene was a main selective factor for the process of environmental changes in this vast territory. Although different concepts of the Plio-Pleistocene boundary have been provided, its boundary can not exceed over 2 mya. Instead of the traditional zoogeographical dicthomy in China, faunal compositions of Pleistocene are divided into three faunal zones. The knowledge of macrofaunal evolution in China are useful to understand the palaeoecology of East Asia. Palaeoenvironment of Korea during the Pleistocene Period can be reconstructed by using the analogy of the current Chinese studies.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.185-196
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• 2010

The distribution of benthic macroinvertebrates in Daecheon stream, an urban stream of Busan, was investigated to analyze the community structure of benthic macroinvertebrates. The collection was performed monthly at five(A~E) sites divided into three parts, upper, middle and lower, of stream from January to November, 2004. In physicochemical analysis of environmental factors, water quality parameters such as BOD, COD, conductivity and ABS were relatively increased in sites B and C. Whereas sites A, D and E showed little variations with good water quality parameters. However, water quality parameters in all surveyed sites showed gradual decrease with time toward improvement of water quality. A total of 8,226 individuals including 4 phyla, 6 classes, 9 orders, 302 families and 44 species were identified from five sites. The most dominant group was insect(class Insecta), and order Ephemeroptera and Diptera among insect was the largest member in species(30.6%) and individuals(75.0%) of benthic macroinvertebrates, respectively. The primary dominant species were Gammarus sp. and Ephemera strigata in site A, whereas Chironomus sp. and Brenchiura sowerbyi were dominated commonly in the other sites. In community analysis of benthic macroinvertebrates of Daecheon stream diversity index showed relatively low values, whereas dominance index was significantly high. Diversity index was the highest in site A, whereas the dominance index was the highest in site B. However, diversity index showed gradual increase with time showing adverse mode in dominance index. From these results, it can be suggested that long-term ecological monitoring of benthic macroinvertebrate fauna is needed for sustainable management of Daecheon stream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.224-229
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• 1987

The ecological studies of the benthic polychaetes of the Yellow Sea were carried out for five years from August 1982. The emphasis of the research were placed on clarification of the distributional pattern and characteristic species of environmental factors on the polychaete community. Based on the polychaete samples analysed during the study period, it was possible to divide the polychaetes into five ecological groups : 18 warm water, 22 cold water, 20 cosmopolitan, 29 endemic, and 7 amphi-pacific species, Anaitides koreana, Aglaophamus sinensis, Nephtys polyoranchia, Nephtys caeca, Glycera capitata, and Scoloplos armiger seem to be characteristic species of sand bottom, while Haploscoloplos elongatus and Ophelina aulogaster of mud bottom. A total of 6 benthic communities have been recognized from the dominant benthic fauna found. In each benthic communities, dominant and characteristic polychaete species were clarified according to their ecological types. In general, as echinoderms such as Ophiura kinbergi, Amphioplus megapomus, and Luidia quinaria are distributed widely and found in high density, their influence on the distribution of most polychaetes is clearly shown.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.120-126
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• 1995

This study investigated the soil oribatid mite community at planatations of the Korean white pine, planted in different years. The soil samples $(10\times10\times5cm)$ were taken monthly from Jun 1988 to July 1989, and soil microarthropods in th sample were extracted using the Tullgren funnel for 72 hors. The diversity indices decreased at the older plantation sites with the maximum point in January and the minimum in September. The richness indices showed the maximum point in June and the minimum in may. The dominance indices increased at the older plantation and showed the maximum point in April, May, the minimum in January. The indices of aggregation of Oribatid mites species showed concentrated distribution in the average 1.9. The older plantation, the more indices increase. The seasonal variation of th indices tended to be greatest in April, August and at lowest in January. The richness indices was positively correlated with shannon-wiener, evenness indices. The dominance, aggregation indices was negatively correlated with shannon, evenness, richness indices.

• 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.

• Korean Journal of Ichthyology
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• v.27 no.3
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• pp.238-242
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• 2015

Three specimens (56.7~92.4 mm in standard length) of the small psychrolutid Psychrolutes pustulosus (Schmidt, 1937) were collected by bottom trawl in the coastal waters off Pohang, the southern East Sea, Korea. This species is characterized by large cephalic pores, no markings on the body or fins, no spines on the head, and no notch between the spiny and soft-rayed dorsal fin. We describe specimens the southernmost distribution in the world, and compare them with two congeneric species from Russia. We thus present the first record of Psychrolutes pustulosus (Schmidt, 1937) within the Korean fish fauna and propose the new Korean name "Min-mu-nui-mul-su-bae-gi" for this species.