• Journal of Wetlands Research
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• v.7 no.1
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• pp.129-138
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• 2005

The flora and vegetation of Jang-cheok wetland (Gyeong-nam) was investigated from April 1. 2004 to Feburary 28. 2005. The vegetation plants collected from this area were 18 taxa : 18 species 17 genera 14 families. Hygrophtes were 2 species 2 genera 2 families. Emergent plants were 6 species 5 genera 6 families. Submersed plants were 1 species 1 genera 1 families. Floating-leaved plants were 5 species 5 genera 5 families. Free-floating plants were 2 species 3 genera 2 families. Dominance of life form was investigated Trapa japonica, Phragmites commnis, Leersia japonica by 5 dominance values and Hydrocharis dubia, Ceratophyllum dmersum were 1 dominance values. The community was investigated 5 communities : Leersia japonica community. Trapa japonica community. Nelumbo nucifera community. Miscanthus sacchariflorus community. Phragmites communis community. Dominance species(Leersia japonica) of Leersia japonica community was investigated $1,89g/m^{2}$(Dry weight) and $1,730ind./m^{2}$(Density). Doninance species(Trapa japonica) of Trapa japonica community was investigated $36,25g/m^{2}$(Dry weight) and $15.20ind./m^{2}$(Density). Dominance species(Nelumbo nucifera) of Nelumbo nucifera community was investigated $30.59g/m^{2}$(Dry weight) and $11.20ind./m^{2}$(Density). Dominance species(Miscanthus sacchariflorus) of Miscanthus sacchariflorus community was investigated $180.50g/m^{2}$(Dry weight) and $124.80ind./m^{2}$(Density). Dominance species(Phragmites communis) of Phragmites communis community was investigated $159.50g/m^{2}$(Dry weight) and $60.00ind./m^{2}$(Density). The predominant species of this area was investigated Trapa. Japonica and the other communities was only small area in the waterside area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.327-339
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• 2001

Community structure of macrobenthos was studied at forty one stations of Hampyung Bay, southwest coast of Korea. Three replicate sediment samples were taken at each station in October 1997, using a van Veen grab (surface area $0.1\;m^2$). The types of surface sediment in the sampling area were muddy sandy gravel between bay mouth and bay proper, and gravelly sandy mud between bay proper and inner bay stations. The particulate organic carbon content in the surface sediment was $0.23\sim0.69\%\;(0.44\pm0.10\%)$. A total of 168 species collected during the study period is composed of 58 of polychaetes, 54 of crustaceans, 34 of molluscs and 22 of miscellaneous. The former two taxa together were accounted for $66.6\%$ of the total number of species. The mean density was $1,168 ind./m^2$, comprising $684 ind./m^2$of molluscs ($58.6\%$), $381 ind./m^2$of polychaetes ($32.6\%$), and $90 ind./m^2$of crustaceans ($13.2\%$). The mean biomass was $358.65 g/m^2$, which is consisted of $302.97 g/m^2$of molluscs ($84.5\%$), $24.20 g/m^2$of echinoderms ($6.7\%$), and $19.16 g/m^2$of crustaceans ($5.4\%$). Major dominant species at the inner stations of the study area was Ruditapes philippinarum with a density of $520ind./m^2$($44.5\%$), and Lumbrineris lontifolia with $183ind./m^2$($15.7\%$), while that at bay mouth stations Pitar indecoroides with $56ind./m^2$. Reticunassa festiva, Heteromastus sp., Praxillella affinis, Chone sp. and Tharyx sp. were at from all stations. Based on the cluster analysis, the macrobenthic community in the bay was classified into five station groups depending on sediment types: Group A, a high gravel content in the sediment; Group B, stations with high mud content from bay mouth to bay proper, Group C, stations with fine and poorly sorted sediment from bay proper to the inner bay. The distribution pattern of the number of species, abundance and biomass is discussed in relation to environmental variables.

• Korean Journal of Environment and Ecology
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• v.31 no.3
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• pp.297-317
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• 2017

The research has been conducted in order to classify the vegetation types of natural forest in Mt. Janggunbong, Bonghwa-Gun and establish its following characteristics of stands. Vegetation data were collected by June in 2014 to August in 2016. Based on the 71 quadrates, we carried out an analysis of species-area curve, vegetation types, importance value, species diversity, coincidence method and CCA. As a result of the species-area curve, it was showed the proper investigation, vascular plants consisted a total of 227 taxa; 67 families, 152 genera, 197 species, 3 subspecies, 27 varieties. The forest vegetation was classified into 7 vegetation units, when it comes to a community group, they are classified into the Quercus mongolica community group. As for community, Q. mongolica community group is classified into the Acer pictum subsp. mono community, Pinus koraiensis community and Q. variabilis community. As for group, A. pictum subsp. mono community is classified into Lychnis cognata group and Deutzia glabrata group. The P. koraiensis community is classified into A. komarovii group and P. koraiensis typical group. The Q. variabilis community is classified into Parthenocissus tricuspidata group and Q. variabilis typical group. As for subgroup, P. tricuspidata group is classified into P. tricuspidata typical subgroup and Salix caprea subgroup. As a result of the importance value, Q. mongolica showed highest importance value in tree layer of vegetation units 1, 2, 3, 4 and 5. Betula schmidtii showed highest importance value in tree layer of vegetation unit 6. P. densiflora showed highest importance value in tree layer of vegetation unit 7. In subtree layer, shrub layer and herb layer of vegetation units 6 and 7, Q. mongolica and Q. variabilis showed high importance value. This implying that a vegetation units 6 and 7 is predicted to be composed by Q. mongolica and Q. variabilis. As for species diversity, vegetation units 1, 2 and 3 showed high species diversity(2.130~2.353). It was considered to be due to the topographical characteristics of valley. As a result of coincidence method and CCA, altitude showed high correlation than other environmental factor.

• Journal of Environmental Science International
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• v.14 no.2
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• pp.177-184
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• 2005

This study was to determine the fluctuation in phytoplankton assemblages with regarding to environmental conditions and nutrients, which were surveyed around Mokpo waters in the southwestern waters, Korea. Sampling was carried out on the Mokpo, Sinan, and Wando coasts from March to November 2003. The maximum sea surface temperature was recorded in August, and it ranged around $25^{\circ}C$ regardless of sampling sites. However, salinity in Mokpo waters showed a great variation, which ranged from 5-30 psu and recoded the minimum of 5 psu in July and the maximum of 30 psu in November. Moreover, in Mokpo waters, the chlorophyll a and SS concentration of the surface layer were also the highest values of $20\;{\mu}g\;l^{-1}\;and\;40\;{\mu}g\;l^{-1}$, respectively than those of Sinan and Wando waters. The concentrations of $NH_4-N,\;NO_2-N,\;NO_3-N,\;and\;PO_4-P$ were also he highest values of $0.018\;{\mu}mol\;^l{-1},\;0.062\;{\mu}mol\;l^{-1},\;1.2\;{\mu}mol\;l^{-1}\;and\;0.078\;{\mu}mol\;l^{-1}$, respectively in Morpo waters than those of Sinan and Wando waters. During the period of this study, the majority of the taxa were diatoms; Thalassiosira rotula, Rhizosolenia setigera, Prorocentrum minimum, Chaetoceros curvisetus, Leptocylindrus danicus, Pseudonitzschia pungens, and Chaetoceros spp. were detected in the dominant species of phytoplankton. The dinoflagellates were relatively abundant during the summer season in Wando waters, which attained an abundance of $10-20\%$. In Mokpo waters, DIN/DIP was the highest value of 700 in March, whereas the lowest was shown in Wando waters. However, DIN/DIP value in summer at Wando waters was extremely reversed, which appeared to be associated with the development of dinoflagellates. On the bais of factor analysis using SYSAT 6.0, nutrient showed somewhat correlation with chlorophyll a. Consequently, the process of discharge of fresh water in Mokpo waters plays an important role in extremely fluctuation in nutrients and conditions. Although Wando waters maintains a lack of nutrients, it should be influenced by different water current and may be associated with a concentration of nutrients.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.1-22
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• 2020

In order to evaluate the vertical distribution and distributional pattern of vascular plants in the Samga district of Sobaeksan National Park, vascular plants were surveyed along a hiking trail from the Samga Tour Support Center to the top of a mountain. The elevation range was divided into 11 sections with 100 m intervals from 400 m to 1439 m above sea level.A total of 375 taxa were listed, comprising 92 families, 235 genera, 332 species, 3 subspecies, 37 varieties, and 3 forms. The pattern of species richness along the elevational gradient showed a reverse hump-shaped trend. The species distribution pattern was positively correlated with the soil exchangeable cations Ca²⁺ and Mg²⁺, soil pH, available phosphate, and the warmth index. Furthermore, slope, soil moisture content, and soil exchangeable cations were significantly correlated with species distribution. DCA grouped herb species into two groups. Stands of each section were sequentially arranged from 400 m to 1500 m along an altitudinal gradient. Soil moisture content, soil pH, soil K²⁺ and Na²⁺, available phosphate, and slope were significantly correlated with stand distribution. This study provides important data that could be useful for conservation and the sustainable use of biodiversity in the study area. In order to understand the ecological and environmental characteristics and distribution of plant species, it will be necessary to continuously develop relative studies with continuous monitoring.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.

• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.551-560
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• 2013

Environmental factors and epilithic diatom communities in the lower streams near the harbor region of South Korean peninsula were examined during no monsoon period in May 2013. The sampling of water and epilithic diatoms was conducted at both streams, 19 regulated streams (RS) that there are one or several dams constructed in the river system, and 19 un-regulated streams (US) that there are no dams within the river. A cluster analysis based on the number of species and abundance of epilithic diatoms through the stations, divided into three groups such as groups I (mainly US), II (mixed with US and RS) and III (mainly RS), respectively. Group I showed that water quality is good and high diversity of diatom, while Group II and III was water quality is relatively poor, but not differed in biomass of diatom from Group I. In addition, Group II that had high conductivity, nitrogen and phosphorus, was the lowest in diatom diversity among them. Dominant species were Nitzschia palea (17%) and Navicula seminuloides (11%) in Group I, Nitzschia inconspicua (19%) and Navicula perminuta (9%) in Group II, and Nitzschia inconspicua (15%) and Nitzschia palea (14%) in Group III, respectively. These taxa were widely distributed in brackish water, and not closely related with specific water quality, like eutrophic water. However, the groups II and III belonged to RS, had not only little biomass, but bad water quality such as high concentrations of nutrient and chlorophyll-a. Therefore, to determine the effect of dam construction on the lower water ecosystem, the planktonic algae, which can occur algal bloom in the estuary, also was considered to be a parallel investigation.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.762-770
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• 2016

This study intended to investigate environmental factors including soil and vegetation in order to understand the environmental and ecological characteristics of the Korean endemic species, Syringa fauriei. Syringa fauriei is mainly distributed along the valley and riverside of the Gangwondo and its population is located at an elevation of 121~520m. Consequent to a vegetation survey within natural populations, a total of 320 taxa were identified from 20 quadrates in 4 natural populations. The Syringa fauriei population was classified into Securinega suffruticosa dominant population, Acer pseudosieboldianum dominant population, Amorpha fruticosa dominant population and Sorbaria sorbifolia var. stellipila dominant population. According to the physical and chemical soil analysis, Syringa fauriei habitats contained 1.98~2.81% of organic matter and 0.13~0.20 mg/kg of total nitrogen. The concentrations of cation exchange capacities $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were $0.10{\sim}0.33cmol^+/kg$, $3.44{\sim}20.53cmol^+/kg$, and $0.34{\sim}0.95cmol^+/kg$, respectively. Positive ion substitution capacity was $8.08{\sim}13.68cmol^+/kg$. The pH was 6.28~7.74. The importance value of Deutzia glabrata, Fraxinus rhynchophylla, Alangium platanifolium var. trilobum, Syringa fauriei, Juglans mandshurica, and Salix koreensis in the Syringa fauriei population were 86.99%, 43.97%, 23.01%,18.52, 18.40%, and 11.56%, respectively. Correlation analysis between the vegetation of Syringa fauriei populations and its environmental factors using DCCA revealed that the altitude above sea level and $Mg^{2+}$ were the most influential factors, while dominant populations of Securinega suffruticosa and Acer pseudosieboldianum were spread across areas with high percentages of pH, CEC, and $Mg^{2+}$. Acer pseudosieboldianum population was dispersed in areas with higher $K^+$ compared to Securinega suffruticosa population. The dominant population of Amorpha fruticosa was found to live in places with high altitudes above sea level and with high rates of available phosphate, $K^+$, and rock-exposure.

• Journal of Plant Biology
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• v.38 no.3
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• pp.305-317
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• 1995

The bryophyte communities on the forest floor of the mixed coniferous, deciduous broad-leaf forest and the evergreen coniferous forest of cool temperate and subalpine zones in Chiri Mountains with the highest peak (Cheonwangbong 1915 m) in south-central part of the Korean Peninsula were investigated from the phytosociology viewpoint. As a result, five bryophyte communities were recognized, considering the species composition of vascular vegetation; A. Sasamorpha borealis-Abies koreana/Dicranum scoparium-Plagiothecium silvaticum community, B. Bosta minor-Abies koreana/Anomodon rugelii-Plagiomnium cuspidatum community, C. Abies koreana/Hylocomiopsis ovicarpa-Entodon rubicundus community, D. Abies koreana-Picea jezoensis/Hylocomiopsis ovicarpa-Thuidium kanedae community, E. Abies koreana-Pieea jezoensis/Hylocomium splendens-Pleurozium sehreberi community. Among these, the communities A, B, C and D were distributed in the mixed coniferous and deciduous broad-leaf forest of lower altitudes (1200 to 1700 m) and characterized by the elements of the cool temperate zone. They were confimled as synusies belonging to the Fraxino-Abietetum koreanae Song 1988. The community E was distributed in higher altitudes (1700 m to near the summit) and characterized by the species group of the holarctic elements, e.g. Hyloeomium splendens, Pleurozium sehreberi, Dieranum majus, etc. limited in subarctic; subalpine and arctic; alpine zones. The community E was confirmed as a synusie of the Abieti koreanae-Piceetum jezoensis Song 1991 belonging the Vaecinio-Pieeetea Br.-BI. 1939. Up to date many investigator have described the coniferous forest distibuted above 1200 m in Chiri mountauns as the forest vegetation of subalpine zone. However, from the results of the present study, the boundary of the mixed forest and the true subalpine coniferous forest was elucidated to be ca. 1700 m phytosociologically. Species richness was highest in the community E, and the other four communities showed a similar species richness. Among the species diversity indices, H' and D were high in the communities Band E, low in the communities A and C, and medium in the community D. The values of J' decreased with the increase in altitudes and the community E showed the lowest value. The result of Bray-Curtis ordination revealed that the diversity analysis and the division of the above two forest zones are justifiable. The taxa of the bryophyte communities were composed of 25 families, 46 genera, 73 species, 1 subspecies and 2 varieties.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.257-265
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• 2001

This study was carried out to investigate composition and distribution of the soil microarthropods in Pinus rigida plantations following strip-cutting from May 1998 to April 1999. The results of this study were as follows; 1. The individuals of soil microarthropods found during the research periods were 181, 904 and were identified into 21 orders in 7 classes. The classes were Arachnida, Insecta, Malacostra, Pauropoda, Diplopoda, Chilopoda and Symphyla. 2. The population density of the soil microarthropods was 82,962 individuals at the control area, 62,688 individuals at the reserve area and 36,254 individuals at the cutting area. The microarthropods in the control area were 2 times higher than those in the cutting area. 3. Although the major dominant taxa, Acari and Collembola, decreased in densities at the cutting area, the density reduction in Acari was higher than that in Collembola. This resulted in the increase of Collembola in terms of the relative abundance at the cutting area. 4. Among the total soil microarthropods, Arachnida was 59.74%, followed by Insecta of 39.82%. Such two groups comprise 99.56% of soil microarthropods. 5. According to the relative population density, Acari was 99.18% in Arachnida and 59.25% in the total and Collembola 93.99% in Insecta and 37.42% in the total. Therefore, individuals of Acari and Collembola was 96.67% of the total individuals. And the next abundant groups were Hymenoptera (0.95%), Diptera (0.64%) and Pseudoscorpiones (0.39%). 6. The population density of the soil microarthropods fluctuated seasonally, showing the bimodal pattern, being high in fall and spring. The highest density occurred in November and the lowest in July.