• The Korean Journal of Ecology
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• v.17 no.4
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• pp.471-484
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• 1994

The forest vegetation types and their structural characteristics in Mt. $Mud\v{u}ng$ were investigated by classification method and ordination method. The forest was classified into 7 communities by ristic composition table: Quercus monogolica community, Q. serrata community, Q.acutissima community, Q.variabilis community, Q.dentata community, Pinus densiflora community and Frainus mandshurica community. Considering the moisture gradient, two kinds of distributuin pattern were shown as follows; F. mandshurica, Q. acturissima, Platycarya strobilacea and Staphylea bumalda were distribute at moist habitats, while Q. monogolica, P. densiflora and Q.variabilis at dry habitats. In continuum analysis, each population occupied different distribution area but it was continuously overlapped. On the successional trends of tree species, it is postulated that Q. mongolica species might dominate the altitudinal zone over 700m.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1717-1723
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• 2010

The integrated fixed-film activated sludge (IFAS) system is a variation of the activated sludge wastewater treatment process, in which hybrid suspended and attached biomass is used to treat wastewater. Although the function and performance of the IFAS system are well studied, little is known about its microbial community structure. In this study, the composition and diversity of the bacterial community of suspended and attached biomass samples were investigated in a full-scale IFAS system using a high-throughput pyrosequencing technology. Distinct bacterial community compositions were examined for each sample and appeared to be important for its features different from conventional activated sludge processes. The abundant bacterial groups were Betaproteobacteria (59.3%), Gammaproteobacteria (8.1%), Bacteroidetes (5.2%), Alphaproteobacteria (3.9%), and Actinobacteria (3.2%) in the suspended sample, whereas Actinobacteria (14.6%), Firmicutes (13.6%), Bacteroidetes (11.6%), Betaproteobacteria (9.9%), Gammaproteobacteria (9.25%), and Alphaproteobacteria (7.4%) were major bacterial groups in the attached sample. Regarding the diversity, totals of 3,034 and 1,451 operational taxonomic units were identified at the 3% cutoff for the suspended and attached samples, respectively. Rank abundance and community analyses demonstrated that most of the diversity was originated from rare species in the samples. Taken together, the information obtained in this study will be a base for further studies relating to the microbial community structure and function of the IFAS system.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.378-384
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• 1989

The numerical taxonomy of heterotrophic bacterial community in Lake Soyang was analysed. 95, 115, 88 and 75 strains which were isolated at each season from spring in 1987 to winter in 1988 were clustered by single matching coefficient. The diversity indices (H') were in the range of 0.511-1.684, and the community was most diverse in spring. THe seasonal variation of generic composition was significant. Of the domonant genera, Acinetobacter, Pseudomonas, and Flavobacterium were representative.

• Ocean and Polar Research
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• v.24 no.4
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• pp.407-417
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• 2002

Species composition and abundance of zooplankton were investigated around Dokdo in the East/Japan Sea in autumn 1999 and spring 2000. Vertical and horizontal hauls of a bongo net ($300{\mu}m$ mesh size, 60cm diameter) were made to collect zooplankton sample. Surface temperature and salinity ranged from $24.2^{\circ}C\;to\;25.1^{\circ}C$, and from 32.9psu to 33.2psu in September 1999, respectively. In May 2000, surface temperatures were $13.9^{\circ}C\;and\;14.2^{\circ}C$ at stations of A1 and A8, and salinity was 34.5psu at both stations. Zooplankton community was dominated by copepods which comprised 61% (September) and 60% (May) of total numerical abundance, respectively. The next dominant groups were appendicularians (11%) and chaetognaths (9%) in September 1999, and other crustaceans (27%) and appendicularians (4%) in May 2000. The 15.7% (September) and 23.2% (May) of copepods were in the juvenile stage of copepodites. The most dominant copepods were Oncaea media (10.4%) and Clausocalanus sp. (8.2%) which preferred warm water in September. In contrast, cold-water copepods such as Pseudocalanus minutus (9.4%) and Metridia pacifica (8.0%) were dominant in May. The results of cluster analysis based on Bray-Curtis index showed that zooplankton community were classified into two groups which represented different water mass. The average abundance of zooplankton in September was 2.1 times higher than that in May, and species number of them in September outnumbered that in May by 29 species. Zooplankton community varied in associated with a characteristic of warm waters which affected marine ecosystem differently in the study area depending on seasons.

• Ocean and Polar Research
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• v.36 no.3
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• pp.209-223
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• 2014

The community structure of benthic meiofauna was investigated from seasonal surveys at seventeen stations off the Saemangeum area, in 2007. Ten meiofaunal taxa were identified. Nematodes were the dominant faunal group in all seasons and harpacticoids were dominant only at a few stations. The mean density of meiofauna was 383 indiv. $10cm^{-2}$, highest in May and November (434 indiv. $10cm^{-2}$), lowest in February (284 indiv. $10cm^{-2}$). Meiofaunal mean biomass was $80.49{\mu}gC{\cdot}10cm^{-2}$, highest in November ($99.54{\mu}gC{\cdot}10cm^{-2}$), lowest in February ($51.56{\mu}gC{\cdot}10cm^{-2}$). Cluster analysis revealed that the study area was composed of three benthic meiofaunal communities. There were significant correlations between major meiofaunal groups and sediment composition and the concentrations of heavy metals. The abundance of harpacticoids are positively correlated with silt (0.559, p < 0.01) and clay (0.340, p < 0.01), and negatively correlated with sand (-0.548, p < 0.01). Harpacticoids also showed positive correlations with heavy metals. The community structure of meiofauna in the study area varied seasonally in response to the change of sediment composition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.849-855
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• 2016

The community composition and distribution of fish species in the middle of the Yellow Sea were investigated in summer from 2008 to 2014. A total of 72 demersal fish species from 46 families and 17 orders were collected. The most common species were Larimichthys polyactis, Engraulis japonicus, and Chaeturichthys hexane, which accounted for 72.0% of the total number of individuals while Liparis tanakai, Larimichthys polyactis, and Lophius litulon accounted for 67.8% of the total biomass. A cluster analysis based on the Bray-Curtis similarity revealed that the fish community fell into three groups, according to latitude. Principal Component Analysis (PCA) and correlation analysis showed that variation in bottom water temperature could act as an indicator of variation in community structure and abundance of the dominant species. Characteristics of fish communities, such as the number of species, the total number of individuals ($/km^2$), and biomass ($/km^2$), were highly correlated with bottom water temperature and depth.

• Ocean and Polar Research
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• v.33 no.4
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• pp.457-472
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• 2011

To elucidate the trophic role of heterotrophic nano- and microplankton (HNMP), we investigated their biomass, community structure, and herbivory in three different water masses, namely, south of Polar Front (SPF), Polar Front Zone (PFZ), the Sub-Antarcitc Front (SAF) in the Drake Passage in the Southern Ocean, during the austral summer in 2002. We observed a spatial difference in the relative importance of the dominant HNMP community in these water masses. Ciliates accounted for 34.7% of the total biomass on an average in the SPF where the concentration of chlorophyll-a was low with the dominance of pico- and nanophytoplankton. Moreover, the importance of ciliates declined from the SPF to the SAF. In contrast, heterotrophic dinoflagellates (HDFs) were the most dominant grazers in the PFZ where the concentration of chlorophyll-a was high with the dominance of net phytoplankton. HNMP biomass ranged from 321.9 to 751.4 $mgCm^{-2}$ and was highest in the PFZ and lowest in the SPF. This result implies that the spatial dynamic of HNMP biomass and community was significantly influenced by the composition and concentration of phytoplankton as a food source. On an average, 75.6%, 94.5%, and 78.9% of the phytoplankton production were consumed by HNMP in the SPF, PFZ, and SAF, respectively. The proportion of phytoplankton grazed by HNMP was largely determined by the composition and biomass of HNMP, as well as the composition of phytoplankton. However, the herbivory of HNMP was one of the most important loss processes affecting the biomass and composition of phytoplankton particularly in the PFZ. Our results suggest that the bulk of the photosynthetically fixed carbon was likely reprocessed by HNMP rather than contributing to the vertical flux in Drake Passage during the austral summer in 2002.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.2
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• pp.101-113
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• 2024

This study investigated the species composition and community structure of aquatic organisms captured using coastal beam trawling in Gomso Bay, Jeollabuk-do, from January to December 2022. Throughout the experimental period, a total of 20,246 individuals belonging to 94 marine species were captured, with a combined biomass of 602,828 g. Fish exhibited the highest abundance, comprising 56 species, followed by crustacea (21 species), bivalvia (8 species), cephalopoda (5 species), gastropoda (3 species), and holothuroidea (1 species). The dominant species was Leiognathus nuchalis, constituting 14.0% of the total individuals, followed by Portunus trituberculatus at 12.1%, Oratosquilla oratoria at 10.4%, Crangon hakodatei at 9.9%, and Metapenaeus joyneri at 7.9%. The diversity index ranged from 1.72 to 2.55, with the lowest diversity observed in March and the highest in July. Cluster analysis based on species composition of the 27 most common species showed that aquatic organisms were divided into three groups: spring and summer organisms (Group A) and summer organisms (Group B) and autumn and winter organisms (Group C).

• Journal of Korean Society of Forest Science
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• v.89 no.2
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• pp.173-184
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• 2000

The aim of this study was to characterize the forest vegetation and site of Tongdaesan(Odaesan National Park) for ecological forest management. The deciduous forests of Tongdaesan are the result of cool, temperate climate. Direction and slope morphology contribute to differences in species composition and vegetaion structure. Based on the BRAUN-BLANQUET-approach, 242 releves were recorded and subsequently classified. The vegetation could be divided into two forest community groups, seven forest communities, and several groups. South exposed, dry slopes were covered with forests of the Quercus mongolica-Acer pseudo-sieboldianum community group. Differential species included grasses and sedges, e.g., Calamagrostis langsdorfii, Carex humilis and C. lanceolata. Quercus mongolica-Acer pseudo-sieboldianum community group could be subdivided into Rhododendron mucronulatum var. ciliatum community, Lespedeza${\times}$tomentella community, Carex humilis-Maackia amurensis community, Quercus mongolica-Acer pseudosieboldianum typical community and Pimpinella brachycarpa community. Carex humilis-Maackia amurensis community was divided into Galium kinuta subcommunity and typical subcommunity. Pimpinella brachycarpa community was divided into Vicia venosa var. cuspidata subcommunity and typical subcommunity. On north exposed, more humid and moist sites, forests of the Dryopteris crassirhizoma-Cornus controversa community group were found. This group was subdivided into Acer tschonoskii var. rubripes-Acer tegmentosum community and Deutzia glabrata-Ulmus laciniata community. Deutzia glabrata-Ulmus laciniata community was divided into Acer tegmentosum subcommunity, Saxifraga punctata subcommunity and typical subcommunity.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.576-587
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• 2012

As being actual physiognomical vegetation on Daegwang sand dune in Imjado, the widest area is occupied by Pinus thunbergii community planted as windbreak forest whereas those communities such as Robinia pseudoacacia community, Elymus mollis community, Imperata cylindrica var. koenigii - Elymus mollis community, Carex kobomugi community, Ischaemum antephoroides community, Imperata cylindrica var. koenigii community, Phragmites communis community, Imperata cylindrica var. koenigii - Calamagrostis epigeios community occupy as band shape or patch. According to the result of the data collected and analyzed based on phytosociological method regarding 74 plots of survey area, the species composition of Daegwang sand dune vegetation is classified total 10 vegetation units comprises 7 communities and 5 groups. The 7 communities are classified into Pinus thunbergii community, Robinia pseudoacacia community, Rosa rugosa var. rugosa community, Ischaemum antephoroides community, Carex kobomugi community, Calamagrostis epigeios community, and the sub-units of Pinus thunbergii communities are classified into 3 groups of Pteridium aquilinum var. latiusculum group, Elymus mollis group, Pinus thunbergii topical group and the sub-units of Calamagrostis epigeios communities are classified into 2 groups of Phragmites communis group, Calamagrostis epigeios tipical group. The zonation of vegetation from coastal line indicated with the order of Elymus mollis - Carex kobomugi, Carex pumila, Lathyrus japonicus - Calystegia soldanella - Vitex rotundifolia, Lathyrus japonicus, Ischaemum antephoroides - Rosa rugosa var. rugosa. According to the analysis result of longitudinal section, it was found to be those types with wide width herbaceous vegetation of foredune, smooth slope of foredune, lots of dune ridges with no structure were less vulnerable to erosion of sand dune and advantageous to its recovery.