• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.404-408
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• 2004

인공순환수로 실험구간에 반구구조물을 설치하지 않은 경우와 설치할 경우의 흐름특성을 분석하기 위하여 수치모의를 수행하였다. 수치모의는 FLUNET가 제공하는 RNG $k-\varepsilon$ 모형과 Reynolds Stress 모형을 사용하였으며 음파유속계(ADV)를 이용하여 측정한 결과와 비교분석 하였다. 수치모의와 실험결과의 상관성을 분석한 길과, RNG $k-\varepsilon$과 Reynolds Stress 모형의 계산결과와 실측값의 상관계수는 반구구조물을 설치하지 않은 경우 0.60 - 0.63, 반구구조물을 설치한 경우 0.75 - 0.78로 큰 차이가 없었다. 그러나 계산반복회수의 경우 RNG $k-\varepsilon$ 모형이 Reynolds Stress 모형에 비하여 2 - 5배 정도 빠르다. 두 모형의 걸과가 크게 차이가 나지 않으므로 순환수로 내의 흐름특성을 분석하기 위한 모형으로 수렴속도가 빠른 RNG $k-\varepsilon$ 모형을 선정하였다. 수치모의 결과와 "흐름 메카니즘에 의한 깔따구의 분포(I)- 실험"의 깔따구 분포경향을 비교한 결과 깔따구는 전반적으로 유속과 난류강도가 작은 곳에 분포하였으며 실험구간에 반구구조물이 있는 경우에는 구조물의 상${\cdot}$하류에 깔따구가 분포하였다. 이차류 또한 깔따구의 분포에 영향을 미친다. 향후 흐름특성에 따른 저서생물의 분포경향을 분석을 위하여 전산유체역학의 기법들을 적용하면 깔따구 등의 저서성 대형무척추 동물의 분포와 흐름특성의 관계를 저렴한 비용으로 분석할 수 있을 것이다.

• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.124-134
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• 2018

We analyzed research topics, temporal distribution of field sites, and researcher network of 1,508 limnology publications in the Korean Journal of Limnology (1968~2012) and the Korean Journal of Ecology and Environment (2013~2017). We found that water quality and sediment, phytoplankton, invertebrates, and fish were major subjects during the study periods. Survey of flora and fauna and physiological experiment of freshwater species were the largest subjects during 1970~80s, while other subjects including production, behavior, modeling, and ecological assessment have been rapidly increased since the 1990s. Most of the biological taxa equally studied lotic and lentic system, however, invertebrates and fish related studies more focused on the lotic system. Spatially, the field site of Korean limnology studies was found to be concentrated in main river channels runs through urban areas and artificial lakes than preserved natural areas. Freshwater system, located at the elevation range of 301~400 m (upstream of main channels), had the lowest number of field sites. Collaboration among researchers and different institution types have been steadily increased and expanded as the number of publications increased.

• The Korean Journal of Ecology
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• v.20 no.6
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• pp.461-470
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• 1997

There are 7 classes, 17 orders, and 141 species of benthic macroinvertebrates at the 5 study sites from Feb, '91 to May, '92. Total species frequency number has less variations among sites than seasonal changes. Not considering seasonal changes this indicates that there are some influences from outside pollution sources. Seasonally, Ortho chadiinae sp. 2 take 21.2% share of total species. It was the dominant species in Feb. '91. With total average level Ephemeroptera take 51.3% of total species as first dominant species. Diptera 27.8% as second dominant species and Trichoptera 16.7% as third dominant species. Through these biological indexes, they appear to have unstable living environments in summer at sites 1 and 5. One can see that site 1 is more polluted than site 3 because site 1 has more pollution sources such as pastures and recreation areas.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.49-57
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• 1991

A study on the distribution and community structure of the benthic macroinvertebrates on the intertidal zones of Gapa and Mara islets were carried out from March to June 1991. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 68 families and 132 speies in Gapa islet and of 7 phyla, 12 classes, 23 orders, 49 familis and 90 species in Maara islet. The first and second dominant species and the community dominance indices of the upper tidal zones of Gapa and Mara islets were Nodilittorina exigua, Pollicipes mitella and 79.01, 69.77 respectively. However, the dominant species of the middle and lower intertidal zones of the two islets were not identities and different among the tidal zones.

• Journal of Environmental Science International
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• v.17 no.8
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• pp.879-889
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• 2008

Community structure of benthic macroinvertebrates was investigated from Gigye stream, Pohang, Korea from May to November, 2007. As results, total of 108 species of macroinvertebrates under 49 families, 15 orders, 5 classes in 3 phyla were identified. The number of species was the most abundantly revealed in aquatic insects (class Insecta) with 86 species (82.6%) under 7 orders. The phylum Mollusca (10 species, 9.2%) and the phylum Annelida (6 species, 5.6%) were followed in order. In the class Crustacea, 6 species (5.6%) were distributed. In aquatic insects, the order Odonata was the most abundant taxon (20 species, 23.3%). Seventeen species (19.8%) of the order Ephemeroptera and 16 species (18.6%) of the Coleoptera were followed. The primary dominant species in the stream was Cloeon dipterum of Ephemeroptera. For community analysis, the values of diversity index (H'), evenness index (J'), dominance index (DI) and richness index (RI) were studied and the average values of them were 5.65, 0.84, 0.13, and 13.18, respectively.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.610-618
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• 2015

This study was conducted to find out the influence of sample size (accumulated survey areas) on the seven biological indices of benthic macroinvertebrates. BMI, the index similar to Zeilika-Marvan’s saprobic index, tended to be independent on the variations of sample size. The other indices (Shannon-Weaver’s diversity, Margalef’s richness, Menhinick’s richness, Pielou’s evenness, and Lenat’s EPT index) showed the considerable variations along with the increase of sample size and environmental conditions. To get the appropriate index values, it should be sampled at least 6 replicates more based on 30×30cm Surber sampler. In addition, the habitat heterogeneity index of benthic macroinvertebrates suggested in this study, it will be able to be used for evaluating the heterogeneity of habitats.

• The Korean Journal of Malacology
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• v.5 no.1
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• pp.10-28
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• 1989

A study on the distribution and community structure of benthic macroinvertebrates on the intertidal zone of Cheju Island was carried out from June 1988 to May 1989. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 71 families and 135 species in this study. The dominant species of the upper tidal zone were Nodilittorina granularis and Heminerita japonica, those of the middle tidal zone were Monodonta neritoides and Lunella coronata coreensis, However, Monodonta neritoides and Chlorostoma arhyrostoma lischkei were dominant in the lower tidal zone. Community dominant indices were significantly high in the upper tidal zone. Macuoinvertebrates species which have the ability of resistance to the physical factors such as, strong waves and exposure to the hot sunlight were mainly distributed on the intertidal zone of Cheju Island. The difference in the number of species among seasons was not significant, but thao among zones was quite apparent and the lower the zone, the more abundant.

• Journal of Korean Society on Water Environment
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• v.31 no.2
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• pp.142-150
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• 2015

The relationship between the number of benthic macroinvertebrate species and the accumulated survey area were investigated in a clean stream and an impaired stream of Korea. Five models to characterize species-area functions were compared, and the Weibull model fitted species-area data well. The other models (Arrhenius, Romell-Gleason, Kylin, Lognormal model) had small or notable bias. The maximum number of species and half-saturation area derived from the Weibull model may be used as the indicators of the carrying capacity and the habitat complexity respectively.

• The Korean Journal of Malacology
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• v.9 no.2
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• pp.68-84
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• 1993

A study on the distribution and seasonal changes of the benthic macroinvertebrate community was performed on the 4 intertidal rocky shores of Biyang-do in Chehu Island throughout four seasons from January 1992 to january 1993. The macroinvertebrates composed of 8 phyla, 15 classes, 31 orders, 71 families, 168 species. The seasonal appearing species were 135 species in summer, 127 species in spring, 124 species in winter and 121 species in autumn, respectively. The dominant species of the upper zones were Nodilittorina exigua, Nerita japonica, Pollicipes mitella, the middle zones were Turbo coronata coreensis, Monodonta neritoides, petrolisthes japonicus and the lower zones were Pagurus samuelis, Chthamalus pilsbryi, Chlorostoma argyrostoma lischkei. The community dominance indices of the upper zones were much higher than the middle and lower zones. The seasonal appearnace in species in the lower zones were remarkable, but individual numbes were not. Species diversity and evenness in all investigated zones were highest in spring and lowest in winter. But species richness was highest in summer, lowest in autumm.

• Journal of Korean Society on Water Environment
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• v.29 no.6
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• pp.790-798
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• 2013

Benthic macroinvertebrates are widely used as biological indicators for assessing the integrity of aquatic ecosystem. However, sampling has usually been done with fixed sample size due to time consuming and costly process. This study was conducted to find out the influence of sample size on the biological indices (H' DI, R1, J, EPT, ESB and BMI) of benthic macroinvertebrates. The 15 replicate samples were quantitatively collected from each 3 different site of two mountain streams in May, 2011. With the replicate data, we combined the abundance of each species with all the possible combinations of the sample size. Along with the increase of sample size, the number of species increased continuously and did not converge. BMI showed little difference whereas other biological indices increased or decreased.