• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.294-304
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• 2023

Seasonal variations in the community structure of larval fish assemblage in the coastal waters off Gadeok-do were investigated in May, August and November of 2019, and February in 2020. During the study period, a total of 85 larvae species belonging to 45 families were collected. The dominant species were Engraulis japonica, Gobiidae sp., Clupea pallasii, Decapterus maruadsi, and Callionymidae sp.. These five species accounted for 84.1% of the total number of larvae during the survey period. E. japonica, Gobiidae sp., D. maruadsi, and Callionymidae sp. were the dominant species in the summer, while C. pallasii was the dominant species in the winter. The Species Diversity Index was highest in the summer and lower in the fall and winter months, with the lowest values in the spring. As a result of cluster analysis using the number of individual larval fish showed that they are divided into four seasonal groups. In particular, due to seasonal changes in water temperature, an appropriate growth environment was formed in the summer, and an appropriate hatching water temperature for winter spawning fish species was formed in winter, reflecting the seasonal characteristics of the larval fish community.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.292-301
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• 2001

The ichthyofauna and fish community of the Gap stream water system were studied at 17 sites from March to December, 2000. It was confirmed the presence of 36 species,29 genera in 8 families. Twenty-five species in Cyprinidae was accounted for 69.4% of the total, four species in Cobitidae 11.1% of the total species number. The dominant species in the Gap stream water system was Zacco platypus (relative abundant 52.0%), the subdominant species was Carassius auratus (9.2%). The major dominant species in the each tributary of the Gap stream water system were Zacco platypus (Daejeon stream, 87.0%; Yoodeung stream, 41.5%; Gap stream, 47.5%). Number of Korean endemic species was 12 species in the Gap stream water system and that was a 24.5% of the total Korean endemic species. Ten rare species accounted for less than 0.3% of the total individual numbers. The mean species dominance, diversity and evenness indices of the fish community from the Daejeon stream were 0.76, 0.25 and 0.28, respectively: from the Yoodeong stream, 0.20, 0.65 and 0.83, respectively; from the Gap stream, 0.25, 0.83 and 0.77, respectively. The fish community of the Yoodeung stream was showed closer relationship to that of the Gap stream than to that of the Daejeon stream.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.95-126
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• 2024

In this study, we investigated the vertical distribution and vascular plants on Joryeongsan Mountain in Baekdudaegan, Korea. The results of four field surveys from April to September 2023 identified a total of 552 taxa, representing 491 species, ten subspecies, 43 varieties, six forms, and two hybrids in 314 genera and 101 families. The elevational distribution ranges of 360 taxa of vascular plants were also identified. Among them, 19 taxa were endemic to Korea, and two taxa were rare plants. The floristic target plants amounted to 100 taxa, specifically two taxa of grade V, seven taxa of grade IV, 25 taxa of grade III, 33 taxa of grade II, and 33 taxa of grade I. Seventy-eight taxa were northern lineage plants. In all, 29 taxa of alien plants were recorded in the investigated area, with a naturalized index of 5.3% and an urbanization index of 7.4%. Two plants disturbed the ecosystem. Species richness along the elevation showed a reversed double-hump shape with peaks at low, mid, and high elevations. The results of a cluster analysis showed a high degree of similarity between adjacent elevation sections, except in lowlands. Detrended Correspondence Analysis ordination also supported distinct groups by elevation. Warmth index values ranged from 62.1℃·month to 92.9℃·month on Joryeongsan Mountain. Our results provide primary data on vascular plants and valuable information on the current distribution ranges of plant species on Joryeongsan Mountain. These data could serve as a baseline for comparing species shifts at elevations under future climate changes.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.393-407
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• 1991

The vegetation structure within Chamaecyparis obtusa plantation was analyzed for the purpose of applying the effective forestation method for Chmaecyparis obtusa plantation, tending and regeneration in the southern districts of korea. The results were as follows ; 1. The importance percentage was high in the order of Eurya japonica, Rhus verniciflua, Chamaecyparis obtusa, Lindera erythrocarpa, Carpinus laxiflora, Styrax japonica, Viburnum dilatatum, Zanthoxylum piperitum and Smilax china among the vegetation of Chamaecyparis obtusa. Importance percentage of natural seedling of Chamaecyparis obtusa was high in lower story but gradually decreased in middle story. 2. The basal area of upper trees had a negative correlation with the density of natural seedlings in the middle and lower story, and it represents that the basal area of upper trees had some effect on the density of natural seedlings within understories. 3. The rate of the A and B class by Raunkiaer's frequency was higher in the vegetation of middle story than that of lower story. 4. By Morisita's index, the species of Chamaecyparis obtusa, Rhus verniciflua, Lindera erythrocarpa, Smilax china. Callicarpa japonica and Lindera obtusiloba were randomly distributed at lower story, but they were aggregatively distributed at middle story. At all of middle and lower story, Eurya japonica and Viburum dilatatum were randomly distributed, and Carpinus laxiflora, Zanthoxylum piperitum and Picrasma quassioides were aggregatively distributed. 5. The number of appearance species and the value of species diversity in western survey area were more than that of eastern survey area. 6. The value of species diversity at lower story was higher than that of middle story, and it represents that the number of individuals of appearance species was composed more even at lover story than middle story. 7. According to cluster analysis by similarity index, the survey areas were separated from inland and seacoast districts. 8. Judging from each stories ordination analysis by dissimilarity index, the vegetation was separated from lower and middle story, and the vegetation of lower story was more progressed succession stage than that of middle story. 9. In Chamaecyparis obtusa stands, Eurya japonica had a positive correlation with Sorbus alnifolia, Hex macropoda. Ficus erecta and Trachelospermum asiaticum, but it had a negative correlation with Zanthoxylum piperitum, Carpinus laxiflora and Parthenocissus tricuspidata. 10. In estimation of the productivity of Chamaecyparis obtusa stands, the value of SC (Conic surface) and VP (Parabolic volume) for upper trees was 94.5% and 99.63%, respectively and SC and VP of middle story was 5.49% and 0.37%, respectively. In the species of middle story, material productivity was high in order of Eurya japonica. Lindera eryhrocarpa, Rhus verniciflua. Carpinus laxiflora and Styrax japonica.

• Korean Journal of Environment and Ecology
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• v.25 no.2
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• pp.156-165
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• 2011

It is selected seven sites for marine algal flora and community structure and investigated seasonally from December 2008 to November 2009 in Gogunsan Islands, the west coast of Korea. A total of 58 species including 10 green, 16 brown and 32 red algae were collected and identified. Among these species, 11 species were found throughout the year. Annual mean biomass in dry weight were 213.8 g $m^{-2}$ at Sinsido 1, 143.1 g $m^{-2}$ at Sinsido 2, 133.3 g $m^{-2}$ at Sinsido 3, 164.0 g $m^{-2}$ at Munyeodo, 116.9 g $m^{-2}$ at Seonyudo, and 145.1 g $m^{-2}$ at Jangjado. Maximum biomass was recorded in Sinsido 1, and minimum mean biomass was Sinsido 4. The dominant species based on biomass were Sargassum thunbergii, Ulva pertusa, Sargassum fusiforme and Corallina pilulifera. S. thunbergii was the representative alga occurred at all seasons. The flora investigated could be classified into six functional groups such as coarsely branched form (46.6%), filamentous form (27.6%), sheet form (17.2%), thick leathery form (3.4%), jointed calcareous form (3.4%) and crustose form (1.7%). The R/P, C/P and (R+C)/P value reflecting flora characteristics were 0.33~0.75, 1.11~2.50, 1.47~3.25, respectively. Diversity index (H') and dominance index (DI) indicated that stability of seaweed community of Gogunsan Islands was unstable and environmental conditions were bad. According to multidimensional scaling (MDS) and cluster analysis, Gogunsan Islands were divided into three distinct groups. The first group was Sinsido 2, Sinsido 3, Seonyudo and Muyeodo and the second group comprised Sinsido 1 and Jangjado and the other was Sinsido 4 due to meaningful difference in similarity.

• Journal of Life Science
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• v.25 no.3
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• pp.257-262
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• 2015

The genetic variability of four species of the genus Zoysia collected from South Korea was analyzed using an inter-simple sequence repeat (ISSR) marker system. Polymerase chain reactions (PCR) with eight ISSR primers generated 86 amplicons, 76 (87.1%) of which were polymorphisms. The polymorphism information content (PIC) value of the ISSR marker system was 0.848. The percentage of polymorphic loci (P_p) ranged from 41.2% to 44.7%. Nei’s gene diversity (H) ranged from 0.149 to 0.186, with an average overall value of 0.170. The mean of Shannon’s information index (I) value was 0.250. Total genetic diversity values (H_T) varied between 0.356 (ISSR-1) and 0.418 (ISSR-16), for an average overall polymorphic loci of 0.345. Interlocus variation in within-species genetic diversity (H_S) was low (0.170). On a per-locus basis, the proportion of total genetic variation due to differences among species (G_ST) was 0.601. This indicated that about 60.1% of the total variation was among species. Thus, about 39.9 of genetic variation was within species. The estimate of gene flow, based on G_ST, was very low among species of the genus Zoysia (N_m = 0.332). The phylogenic tree showed three distinct groups: Z. macrostachya and Z. tenuifolia clades and other species were formed the separated clusters. In conclusion, the ISSR assay was useful for detecting genetic variation in the genus Zoysia, and its discriminatory power was comparable to that of other genotyping tools.

• Journal of Life Science
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• v.29 no.5
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• pp.580-587
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• 2019

Benthic macroinvertebrates were analyzed in March, June, September, and December 2018 to evaluate water quality in the Songji River in Sacheon-ci, Korea. The identified benthic macroinvertebrates included 447 individuals belonging to 20 species, 18 families, 12 orders, 5 classes, and 3 phyla. Various ecological parameters were estimated for evaluation of the river status. The total ecological score of benthic macroinvertebrate community (TESB) varied from 17 (Station D) to 41 (Station A). The saprobic index and ecological score of benthic macroinvertebrate community (ESB) for the evaluation of river status revealed a water quality evaluation at Station A of II (oligosaprobic), indicating some satisfactory water protection. The benthic macroinvertebrate index (BMI) varied from 25.207 (Site C) to 39.348 (Station A). The evaluation of the river status at Stations C and D was polysaprobic, and sensitive taxa were absent. The mean Shannon-Weaver index (H') of diversity varied from 1.288 (Station D) to 2.250 (Station A). The classification of saprobity based on H' was ${\beta}$-mesosaprobic at Station A and ${\alpha}$-mesosaprobic at the other stations. The value of geometric density was varied from 1.229 (Station A) to 2.071 (Station D), with a mean of 1.582. An artificial load is being added to this river. One of load is the rectal river construction which flows straight through the river physics. Thus, the environment of living organisms deteriorates due to insufficient water. In order to secure the quality of the Songji River and a good environmental habitat, several low-height stepped-beam structures are required.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.1-7
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• 1996

In order to get basic information for establishing weed control methods in greenhouse, weed distribution was surveyed at 42 greenhouses in 10 cities and counties of Gyeongnam and Junnam area from September to December, 1995. Sixty nine weed species in 23 families which were composed of 28 annuals, 16 biennials and 25 perennials were identified. Broadleaf weed species was 50 species, followed by 8 species in grasses, and 11 species in sedges. Cruciferae was the most widely occurring family belong to 9 species, followed by 8 species in Compositae, Cyperaceae and Gramineae, respectively, 6 species in Polygonaceae, and the other 17 families have 1~3 species. The dominant weed species occurred in greenhouses based on summed dominance ratio of weeds were Cardamine flexuosa var. fallax, Digitaria sanguinalis, Eleusine indica, Stellaria aquatica, Centipeda minima, Mollugo pentaphylla, Portulaca oleracea, Rorippa islandica.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.652-663
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• 2019

The purpose of this study was to conduct ecological health assessments by using the fish communities in the Manchurian trout habitat. Sampling was conducted twice in July and September 2018. In the survey, 1,119 individuals belonging to 16 species and seven families were collected. The dominant species by number was Rhynchocypris kumgangensis and the subdominant species was Zacco koreanus. Korean endemic species represented 73.33% at Geybang Stream and 76.92% at Naerin Stream. Community analysis revealed that the structure of the fish community was unstable by the dominance index 0.63 (±0.09)-0.97 (±0.01), the diversity index 1.63 (±0.23)-0.33 (±0.09), the evenness index 0.79 (±0.06)-0.24 (±0.07) and the richness index 0.67 (±0.14)-1.80(±0.16). According to the analysis of the tolerance guilds, the total individual number of sensitive species was higher than the intermediate and tolerant species. The insectivore species accounted for 65.09-98.56% of the total trophic guilds, which was the highest observed. The value of the QHEI (Qualitative habitat evaluation index) in the Brachymystax lenok tsinlingensis habitat was 119.5 (±0.5)-153.5 (±0.5), indicating an optimal-suboptimal condition. The FAI (Fish assessment index) stream health value was A to B in the study sites. Correlation analysis with FAI and various factors was conducted and a high correlation in QHEI, Brachymystax lenok tsinlingensis individuals, species, individuals, diversity, richness, sensitive species, carnivorous species, insectivorous species, and omnivorous species was found. The similarity analysis was divided into three groups from A to C, based on 56.9%.

• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.509-520
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• 1997

This is a report on the early vegetation, plant community structure, and secondary succession of cut and uncut sites of burned areas in Mt. Gumo-sun. The forest fire occurred on April, 1994 and the pine forest and its floor vegetation were burned down. The investigation was carried out from April, 1995 to October, 1996. The results are summarized as follows : The floristic composition of cut and uncut sites of burned area and unburned area were composed of 32, 36, and 34 kinds of vascular plants respectively. The biological spectra showed the $H(G)-D_1-R_5-e$ type, $H(M)-D_1-R_5-e$ and $M(N)-D_1-R_5-e$ in cut, uncut, and unburned site respectively. The dominant species based on $SDR_3$ of the cut site were Miscanthus sinensis var. purpurascens(100.00). Caret humilis(52.27), Quercus serrata(51.19) and Lysimachia clethroides(39.40), however, in the uncut sites the dominant species were Quercus acutissima(56.91), Pinus densiflora(26.83) in the tree layer, Quercus serrata(50.43), Lindera glauca(40.51), Lespedeza bicolor(37.85) in the shrub layer, and Miscanthus sinensis var. purpurascens(72.27), Pteridium aquilium var. latiusculum(60.92), Carex humilis(63.63) in the herb layer. Pinus densiflora(99.88), Miscanthus sinensis var. purpurascens(82.74), Quercus serrata(77.47) and Carex humilis(74.02) were dominant in the unburned site. The species diversity(H) and evenness index(e) were 1.05, 0.70 and 1.32, 0.85 in the cut and uncut site, respectively and 0.22, 0.63 in the unburned site. Dominance index(C) was 0.15, 0.06 and 0.96 in the cut, uncut site and unburned site, respectively. Degree of succession(DS) was 345.19, 747.47 and 674.34 in cut, uncut and unburned site, respectively. The index of similarity(CCs) was 0.66 between cut and uncut sites, 0.50 between unburned and cut sites and 0.61 between unburned and uncut sites. The amount of exchangeable sodium, calcium, magnesium and soil pH were increased, but the amount of organic matter, available phosphous, total nitrogen, total carbon and exchangeable potassium were decreased in cut site after fire.