• Korean Journal of Environmental Biology
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• v.28 no.4
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• pp.179-187
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• 2010

The Theory of Island Biogeography describes that the number of species on an island affected by island area and distance from the mainland. This study was performed to compare and analyze the community structure of the macro-invertebrates in three isolated islands, around Korean waters in terms of the Theory of Island Biogeography. Macrobenthic animals were collected using a modified underwater quadrat in August 2009. A total of 104 macrobenthic species were sampled with a mean density of 399 individuals $m^{-2}$ and biomass of 1,506.70 g $m^{-2}$. Based on the abundance and biomass data, there were 10 dominant species accounting for approximately 67.17% of total individuals. The highest densities were found in the amphipoda Amphipoda spp., the bivalvia Modiolus agripetus and Mytilus coruscus, the Sipunculida Phascolosoma scolops and the polychaeta Syllidae unid.. On the contrary, the top ten species made up 95.66% of the total biomass while the three most abundant, the bivalves M. coruscus, Streostria circumpicta and M. agripetus. The conventional multi-variate statistics (cluster analysis and non-metric multi-dimensional scaling) applied to assess spatial variation in macrobenthic assemblages. Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 2 station groups. The group 1 was consisted with Gageodo (except for lower station at Transect 2) and Dokdo station and was numerically dominated by the polychaetes Eunice antennata and Syllidae unid., the cirripedia Megabalanus rosa and the bivalvia M. coruscus. However, group 2 was associated with Sohwado station and was characterized by high abundance of the anomura Petrolisthes japonicus, the gastropoda Lirularia pygmaea and the brachiopoda Coptothyris grayi. In conclusion, these results suggested that the species diversity and community structure of macrobenthos in three isolated island seemed slightly related to island area and distance from the mainland.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.46-56
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• 2012

Benthic macroinvertebrates were investigated in Hoeongseong Lake region from March to October 2010, Korea. Macroinvertebrate communities, composition of the functional feeding groups, habitiat oriented groups and the biological water quality were assessed above and below Hoeongseong Dam in the lake region. Six sites, two (St.1~2) above the lake, two (St. 3~4) into the lake, and two (St. 5~6) below the dam, were selected for quantitative (Surber sampler $30cm{\times}30cm$, mesh size 0.2 mm) and qualitative (Hand net) samplings of benthic macroinvertebrates. As a result, a total of 83 species belonging to 43 families, 17 orders, 8 classes, and 5 phyla were recognized. The EPT-group (50 spp. : 60.24%) that is major taxa or EPT-group plus Diptera (61 spp. : 73.49%) occupied most of benthic macroinvertebrates community. Based on quantitative sampling, the number of benthic maroinvertebrates above the lake was 2,399 individuals including 54 species, 28 families, 11 orders, 4 classes, and 4 phyla, whereas 510 individuals including 16 species, 12 families, 7 orders, 4 classes, and 3 phyla in the lake and 626 individuals including 62 species, 33 families, 13 orders, 6 classes, and 4 phyla below the dam were collected respectively. Dominance index was the highest, with 0.82-0.93 ($0.87{\pm}0.05$) in Hoeongseong lake (St. 3-4), diversity index was 3.04-3.16 ($3.10{\pm}0.06$), evenness index was 0.79-0.85 ($0.82{\pm}0.03$), and richness index was 7.27-8.52 ($7.90{\pm}0.63$), which were relatively higher below the dam sites. In the functional feeding groups, collector-gatherers and collector-filterers were the highest in the whole sites, and predators (Micronecta sedula) was appeared highly in the lake. Moreover, swimmers, burrowers, and clingers were considerably occupied in all collecting sites. The result of the DCA, similarity analysis, and MRPP were well reflective of the composition of lake and stream macroinvertebrates. ESB indicate that the lake sites were evaluated heavily polluted under priority improvement waters. Also, Semisulcospira gottschei, Ecdyonurus kibunensis, Epeorus pellucidus, Rhoenanthus coreanus, Stenelmis sp., and Cheumatopsyche brevilineata are considered as an indicator species above and below Hoeongseong Lake, whereas Macrobrachium nipponense and Micronecta sedula are indicated in the lake.

• Korean Journal of Environment and Ecology
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• v.37 no.4
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• pp.259-272
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• 2023

This study set up 49 survey areas with an area of about 400 square meters in Abies koreana natural habitat to identify the species composition and vegetation structure of the A. koreana forest in the Mt. Jiri Nation Park, conducted field surveys using phytosociological methods, and performed the cluster analysis using the Two-Way Indicator Species Analysis (TWINSPAN) and Table manipulation. Subsequently, species composition analysis using the importance value, species diversity analysis, DBH analysis, sapling analysis, and similarity analysis was conducted by each cluster type. The cluster analysis classified the A. koreana forest in Mt. Jiri into five clusters, A, B, C, D, and E. The forest was divided into two clusters, Magnolia sieboldii-Dryopteris crassirhizoma-Sasa borealis and Betula ermanii-Solidago virgaurea-Calamagrostis arundinacea. The former was classified as type A and B by Cornus controversa-Hydrangea macrophylla, and the latter was classified as type E, a typical community, and a Sorbus commixta-Rhododendron mucronulatum cluster. And the S. commixta-R. mucronulatum cluster was divided into C type and D type by Picea jezoensis-Ligularia fischeri and Ainsliaea acerifolia. Through vegetation analysis, the importance value of A. koreana, Quercus mongolica, Acer pseudosieboldianum, Fraxinus sieboldiana, and B. ermanii was highly expressed in the A. koreana forest in Mt. Jiri. Regarding species diversity, the results were similar to those reported in other studies of A. koreana forests in Mt. Jiri. The analysis of diameter at breast height (DBH) showed that A. koreana dominated all layers, and the growth of saplings was also good, indicating that the dominance of A. koreana is expected to continue for a while. However, when considering the value of biodiversity that is expected to increase and threats caused by climate change, systematic preservation and management are required to respond to various threats based on continuous monitoring.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.1-8
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• 2014

Twelve Universal fungal PCR fingerprint (UFPF) primers that were modified from Universal rice primer (URP) were used to assess genetic diversity of 64 Agaricus strains including 45 A. bisporus strains and other 19 strains of other Agaricus spp. Eight primers, UFPF1, UFPF2, UFPF3, UFPF7, UFPF9, UFPF10, UFPF11, and UFPF12 produced PCR polymorphic bands within and between the Agaricus species. Primer UFPF7 produced specific PCR polymorphic bands that are distinct Korean strain from different strains. Ninety five PCR polymorphic bands were inputted for UPGMA cluster analysis. Forty five strains of A. bisporus are genetically clustered into 8 groups, showing coefficient similarity from 0.75 to 0.9 among them. The varieties, Saea, Saedo, Saejeong and Saeyeon that have recently been developed in Korea were involved in the same group with close genetic relationship of coefficient similarity over 0.96, whereas, other Korean strains were genetically related to A. bisporus strains that were introduced from USA, Eroupe and Chinese.

• Journal of Life Science
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• v.28 no.8
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• pp.955-961
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• 2018

Although much research has focused on various bioactive substances in starfish, research on microorganisms isolated from starfish is lacking as compared with other natural products. In this study, we investigated bacterial communities in the gut of red starfish (Certonardoa semiregularis) in Jeju Island. In total, 103 bacterial strains were isolated using marine agar and R2A medium. The isolated strains were analyzed and identified using the 16S rRNA gene sequence. Based on an analysis of this gene sequence, the 103 isolated bacteria were classified into four major groups: Proteobacteria (93%: Alpha-proteobacteria, 24.8%; Beta-proteobacteria, 4%; Gammaproteobacteria, 65%) Bacteroidetes (4%), Actinobacteria (2%), and Firmicutes (1%). In addition, the isolates were divided into seven classes (Actinobacteria, Flavobacteria, Bacilli, Sphingobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria), 15 orders, 19 families, and 24 genera. A phylogenetic analysis revealed two strains, Lysobacter sp. and Pedobacter sp., with similarity of 97.55% and 97.58%, respectively. As the similarity in the 16S rRNA gene sequence was 98% or less compared to previously identified bacteria, the two strains may possibly be classified as a new genus or species. We suggest that additional studies, including biochemical and morphological tests, should be performed to identify the new candidate strains.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.556-565
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• 2010

Community analysis based on functional feeding groups of benthic macro invertebrates at Wangpi-cheon was assessed with the result of four field survey from October, 2007 to May, 2008. A total 138 species of benthic macro invertebrates in 58 families, 16 orders, 6 classes, and 4 phyla were collected during the field surveys. The result of EPT index value showed high value of 61.59% and it means that the stream ecosystem of Wangpi-cheon is very clear and healthy. In this study the functional feeding groups in Wangpi-cheon were divided into two groups. First, Scrapers and Collectors-Gathering group which is normally dominant in midstream showed higher dominance in main stream than tributary. Second, shredders group showed higher dominance in tributary than main stream like as the general characteristics of upriver. With the result of cluster analysis based on the similarity index, the study areas could be grouped into a natural area(A group) and an artificial disturbance area(B group; site 8 and 11) where embankment, bank and levee had been built near by. And also, the natural area(A group) was classified into two groups which had the characteristic of main(site 1, 2, 3, 4 and 7) stream and tributary(site 5, 6, 9 and 10) respectively.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.97-103
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• 2011

Two Gram positive bacterial strains, designated strain GC-1 and GC-4, were isolated from coastal seawater near Jeju Island in the Republic of Korea. The two strains were identified as members of the genus Bacillus, based on 16S rRNA gene sequencing and data for physiological characteristics analyses. A subtle difference in physiological and genotypical characteristics has led us to designate the strains GC-1 and GC-4. The strain GC-1 showed a 99.91% similarity in 16S rRNA gene sequencing with B. tequiliensis and B. subtilis subsp. inaquosorum and the strain GC-4 showed a 100% similarity in 16S rRNA gene sequencing with those of B. altitudinis, B. stratosphericus, and B. aerophilus. However, both strains exhibited different physiological and genotypical characteristics in many aspects from those of their phylogenetically closest neighbors listed above, which implies that genus Bacillus has diversified into various species during its evolutionary process.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.137-142
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• 1985

This experiment was conducted to know the difference in weed population in the five cropping patterns kept same for six years from 1976 such as ricebarley, potato-rice, pea-rice, rice-rye, and rice-fallow. More and many weeds were growing in single cropping field than double cropping field. Dominant weed species in pea-rice and potato-rice cropping patterns were M. vaginalis and S. hotarui, M. vaginalis and P. distinctus. Coefficient of similarity of the cropping patterns between pea-rice and potato-rice appeared higher than single cropping system. However, pea-rice and rice-fallow cropping patterns showed low coefficient of similarity.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.319-327
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• 2000

The feeding behavior of 1-year-old silver carp, Hypophthalmichthys molitrix (Val.) on phytoplankton species in a shallow hypertrophic lake was studied from 22 May to 18 September, 1997. Over the experimental period, the filter-pore sizes of the fish, the total biomass of the phytoplankton and the water temperature in each enclosure changed little with time. The fish biomass in each enclosure increased with time, while their percentage of weight gain correlated negatively to the stocking density, due perhaps to competition for prey. An analysis of gut contents of silver carp showed a strong similarity between the algal communities in the foregut and the water, and was significant for the fish enclosure with a low density (p<0.05). The presence of silver carp rarely suppressed the abundance of phytoplankton such as Oscillatoria, Anabaena and Melosira even at high ingestion levels. There were weak relationships between the IU values of each phytoplankton and the selectivity of fish on them (r = 0.001, p>0.5). There was no doubt that the silver carp fed unselectively when cyanobacteria populations were high, even though the selectivity index for diatoms was slightly higher than those for cyanobacteria, green algae and cryptomonads. Improvements in methodologies are needed to clearly understand and generalize the feeding behavior of silver carp.

• The Korean Journal of Mycology
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• v.35 no.2
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• pp.61-67
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• 2007

Twelve URP primers were used to assess genetic characteristics of oyster mushroom including 59 Pleurotsu ostreatus cultivars, two of P. florida cultivars, one P. sajor-caju cultivars, one P. abalonus cultivar and two P. eryngii cultivars registered in Korea. Six URP primers produced PCR polymorphic bands within and between the Pleurotus species. Primer URP2F produced distinct cultivar specific PCR polymorphic bands that profiled to 15 cultivar types. PCR polymorphic bands amplified by URP2F, URP6R, URP4R and URP2R were used for UPGMA cluster analysis. Fifty nine cultivars of Pleurotus ostreatus are genetically clustered into 5 groups, showing genetic similarity over 70% among them and P. abalonus. P. eryngii and P. sajor-caju, were involved in outside groups.