• Ecology and Resilient Infrastructure
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• v.2 no.1
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• pp.22-32
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• 2015

This study investigated the difference in fish community structures in a main channel and an isolated former channel, considering the environmental factors in the Mangyeong River, Korea. Principal component analysis (PCA) with environmental factors showed that former channels were composed of a fine substrate covered by in-stream vegetation, whereas the main channel was covered by a wide range of substrates with a higher dissolved oxygen and conductivity. The result of the hierarchical cluster analysis with species abundance delineated to the four main groups; three abandoned channel groups and one main channel group. Non-metric multidimensional scaling (NMDS) showed that fish community structures of each study site differed from environmental factors: former channel fish communities were positively related to in-stream vegetation cover, whereas main channel fish communities were positively associated with dissolved oxygen and conductivity. The results indicated that channelization, where there was a separation between the former channel and the main channel, had detrimental effects on fish community structures of both the main channel and the abandoned channel in the Mangyeong River. In conclusion, this study suggested that the connectivity between the main channel and abandoned channel were required to enhance both habitat structural diversity and species diversity of the Mangyeong River.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.197-204
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• 2014

The purpose of this study was to investigate the vegetation structure of Daphniphyllum macropodum community in the Yeong-sil and Seong-panack. To do so, 26plots ($(20m{\times}20m)$) were set up and surveyed. Plant communities were classified with 3 groups according to the analysis of classification by TWINSPAN and DCA Ordination; Pinus densiflora-Carpinus laxiflora (I), Carpinus laxiflora-Quercus serrata (II) and Carpinus tschonoskii (III). Daphniphyllum macropodum is appearing in understory and shrub layer of all groups. We found that Daphniphyllum macropodum will be dominated in understory and shrub layer. These results was judeged that these influence is depended on difference of altitude and accompanied species. Accompanied species were lived in similar growth environment to Daphniphyllum macropodum. That species were Styrax japonica, Quercus serrata of understory and Ilex crenata, Taxus cuspidata of shrub layer.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.147-153
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• 1993

The Dalbatjae-Birobong ridge forest in Mt. Sobaek area was studied to investigate forest community structure. Twenty 20m $\times$ 25m plots were set up in the studied ridge forest along altitude of 770m to 1,410m and vegetation analysis for tree stratum of the trees above 1cm DBH was carried out. The leading dominant tree species were Pinus densiflora in the lower elevation and Quercus mongolica in the higher elevation. According to importance value and cluster analysis, the studied ridge forest was classified into four forest communities of Pinus densiflora community, Pinus densiflora-Quercus mongolica community. Quercus mongolica community and Quercus mongolica-deciduous tree species community. According to importance value of major tree species in canopy and understory, the present community type seems to continue for a relatively long time. Species diversity of Pinus densiflora community, Pinus densiflora-Quercus mongolica community, Quercus mongolica community and Quercus mongolica-deciduous tree species community were 0.6791, 0.6850, 0.5296 and 0.7136, respectively.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.1
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• pp.9-16
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• 2011

An approach to understand the phase distribution in a multi-phase polycrystalline material is important since it can affect material properties and mechanical behaviors. A proper method is needed to describe the phase distribution. For this purpose, contiguity and probability functions(two-point correlation and lineal-path functions) are investigated for representing the phase distributions of microstructures. The mechanical behaviors are evaluated using the finite element method. The characteristics of probability functions and mechanical reponses of virtual samples are represented. It is confirmed that the topology of phase clustering affects the mechanical behavior of materials and that the strength is reduced as the clustering size increases.

• Korean Journal of Environment and Ecology
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• v.14 no.1
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• pp.46-56
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• 2000

Vegetation structure of $Hwangs\v{o}ng$ Park in $Ky\v{o}ugju$ was investigated to study ecological value and to suggest a desirable management proposal. To do this, twenty plots were set up and surveyed. The $Hwangs\v{o}ng$ Park forest was classified into five plant communities by the DCA technique, which were two types of Pinus densiflora communities, Quercus spp.-P. densiflora, Robinia pseudoacacia and Q. mongolica community. In the diversity analysis, 29 woody species were observed, but species composition was simple. No. of average species is $5.4\pm2.9$ per a plot($100m^2$), and Pinus densiflora is a dominant species in DBH $27\sim47cm$ class. From the results of tree ring and growth analysis, it was found out that pinus densiflora community of $Hwangs\v{o}ng$ Park has a historical and ecological value, but recently the growth rate was decreasing. The management proposal was suggested upon to the above results.

• Korean Journal of Environment and Ecology
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• v.11 no.4
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• pp.433-449
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• 1998

To study the plant community structure of Chayang-chon area from Jangsudae to Hangyeryung in Soraksan National Park, 62 plots(each size 100m$^2$) were set up and surveyed. Six communities(Pinus densiflora - Populus caximowiczii community, P. densiflora community, P. densiflora - Deciduous broad-leaved tree community, Quercus mongolica community, Q. mongolica - Carpinus cordata community, C. cordata - Deciduous broad- leaved tree community) were classified by DCA ordination techniques. Q. mongolica community, Q. mongolica - C. cordata and C. cordata - Deciduous broad-leaved tree community were distrivuted over altitude 755m, and the others were distributed below there. In the community over altitude 755m, the succession that Q. mongolica community changed to C. cordata community have proceeded partly and otherwise C. cordata community and Deciduous broad-leaved tree community have been competing with each other. In the community with distribytion range from 500m to 560, high, P. densiflora community would change deciduous broad-leaved tree community forward.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.121-134
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• 1995

To investigate the plant community structure in Pinus densiflora forest of Chuwangsan National Park, twenty five plots were set up and surveryed. The classification by TWINSPAN and DCA ordination techniques were applied to the study area. The plant community were divided into five groups in twenty five plots by DCA and the dividing groups were Pinus densiflora-Quercus variabilis community(I), P. densiflora-Q. serrata community(II), P. densiflora-Fraxinus sieboldiana community(III), P. densiflora-F. sieboldiana-Q. spp. community(IV) and P. densiflora-mixed deciduous forest community(V). The successional trends of tree species by DCA ordination techniques and DBH class distribution analysis seems to be from P. densiflora through Q. mongolica, Q. serrata to Carpinus laxiflora in the canopy layer group. And in the subtree and shrub layer, it was expected that Lespedeza maximowiczii, L. cytobotrya, Rhododendron mucronulatumlongrightarrowStyrax obassia, Stephandra insisa, Zanthoxylum schinifolimlongrightarrowAcer pseudo-sieboldianum, Lindera obtusiloba. There was no difference between the stand scores of DCA and soil pH, and soil moisture.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.135-154
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• 1994

To investigate the forest structure in valley of Kumpotan-Paekryunsa of Tokyusan National Park, fourty plots were set up and surveyed. According to the analysis of classification by TWINSPAN, community divided by 8 groups. The divided groups are Carpinus laxiflora-C. cordata community(I), Pinus densiflora-C. laxiflora-Quercus serrata community(II), C. laxiflora community(III), Q. mongolica-C. laxiflora community(IV), Q. spp. community(V, Ⅵ), and Fraxinus mandshurica community(Ⅶ, Ⅷ). In the analysis of ordination techniques, DBH distribution, environmental variables etc., community Ⅶ and Ⅷ were pointed out edaphic climax. So the successional trends seems to be from P. densiflora through Q. mongolica, Q. serrata to C. laxiflora, C. cordata, F. mandshurica in canopy layer. And in the subtree and shrub layer, it was expected that Rhododendron mucronulatum, Rh. schlippenbachii, Rhus trichocarpalongrightarrowAcer pseudo-sieboldianum, Lespedeza maximowiczii, Euonymus oxyphyllus, Symplocos chinensis for. pilosalongrightarrowStaphylea bumalda, Weigela subsessilis. According to the results of the analysis for the relationship between environmental variables and species, F. mandshurica correlated with exchangeable cations significantly.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.113-127
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• 1996

To investigate the plant community structure and to establish restoration counterplan of forest area in Seoul, fifty six plots(each size was 400m$^{2}$) were set up and surveyed. According to analysis DCA ordination techniques, the communities were divided into six community, P. rigida community, Populus * albagladulosa community, Quercus acutissima community and Q. monholica community. The successional trend of forest area in Seoul was seem to Pinus densiflora, Robinia pseudoacacia, P. rigida, Populus * albagladulosa, Wuercus acutissima$\longrightarrow $Q. mongolixa, Q. serrata by analysis of plant community structure. Shanon's diversity was 1.1381~1.2694 and Soil pH was 3.18~4.76 in survey sites.

• Korean Journal of Environment and Ecology
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• v.10 no.2
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• pp.270-282
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• 1997

This investgation was performed to provide basic data for the management program of the Soraksan national park. Sixty plots were set up and surveyed in the Sinhungsa-Wasondae Area. The vegetation was divided into two communities, Pinus densiflora community and Quercus serrata community, according to the analysis of DCA ordination. It was found out that the succession of the Pinus densiflora comunity would proceed to Quercus serrata community of which components was dominant in understory layer and shrub layer. And it was found out that in the Quercus serrata community the Pinus densiflora being mainly big size in DBH would becomr dominant comtinuously. Shannon's diversity of both community were 1.2554 and 1.1134 respectively. The numbers of woody species per 100m$^{2}$ ranged 7 to 26, and the average number of woody species was 13.