• The Korean Journal of Ecology
• /
• v.20 no.2
• /
• pp.125-132
• /
• 1997

A study of forest vegetation in Mt. $T\v{o}kyu$ National Park was investigated by ordination technique. By TWINSPAN(Two-Way Indicator Species Analysis) method, 10 groups were recognized as follows: pinus densiflora, Quercus variabilis, Quercus serrata, Quercus mongolica-Rhododendron schlippenbachii, Quercus mongolica-Abies koreana, Quercus mongolica-Acer pseudo-sieboldi-amum, Quercus mongolica-Symplocos chinensis for. pilosa, Carpinus laxiflora, Fraxinus mandshurica and Taxus cuspidata groups. The floristic composition of these groups showed high correlation to soil moisture(r=0.831), altitude(r=0.784), topography(r=-0.722), organic matter(r=0.642), and pH(r=-0.509) among various environmental factors. According to the results of CCA(Canonical Correspondence Analysis) Pinus densiflora group and Quercus variabilis group were situated in a xeric area at a lower altitude where soil nutrients were poor compared with the other groups. Fraxinus mandshurica group was distributed throughout the valley with high soil moisture and good nutrients, Quercus serrata group and Carpinus laxiflora group were found in the low altitude region with good nutrients, Quercus mongolica group, at the high altitude region with good nutrients, and Quercus mongolica-Acer koreana and Taxus cuspidata at higher altitudes(1, 400-1600 m).

• Journal of Embryo Transfer
• /
• v.30 no.1
• /
• pp.33-43
• /
• 2015

Successful somatic cell nuclear transfer (SCNT) has been reported across a range of species using a range of recipient cells including enucleated metaphase II (MII) arrested oocytes, enucleated activated MII oocytes, and mitotic zygotes. However, the frequency of development to term varies significantly, not only between different cytoplast recipients but also within what is thought to be a homogenous population of cytoplasts. One of the major differences between cytoplasts is the activities of the cell cycle regulated protein kinases, maturation promoting factor (MPF) and mitogen activated protein kinase (MAPK). Dependent upon their activity, exposure of the donor nucleus to these kinases can have both positive and negative effects on subsequent development. Co-ordination of cell cycle stage of the donor nucleus with the activities of MPF and MAPK in the cytoplast is essential to avoid DNA damage and maintain correct ploidy. However, recent information suggests that these kinases may also effect reprogramming of the somatic nucleus and preimplantation embryo development by other mechanisms. This article will summarise the differences between cytoplast recipients, their effects on development and discuss the potential role/s of MPF and or MAPK in nuclear reprogramming.

• Journal of Forest and Environmental Science
• /
• v.37 no.1
• /
• pp.14-24
• /
• 2021

A plant community is a group of populations that coexist in space and interact directly or indirectly with the environment. In this paper, we determined the pattern of tree species composition in response to soil variables in Khadimnagar National Park (KNP), which is one of the least studied tropical forests in Bangladesh. Soil and vegetation data were collected from 71 sample plots. Canonical Correspondence Analysis (CCA) with associated Monte Carlo permutation tests (499 permutations) was carried out to determine the most significant soil variable and to explore the relationship between tree species distribution and soil variables. Soil pH and clay content (pH with p<0.01 and Clay content with p<0.05) were the most significant variables that influence the overall tree species distribution in KNP. Soil pH is related to the distribution and abundance of Syzygium grande and Magnolia champaca, which were mostly found and dominant species in KNP. Some species were correlated with clay content such as Artocarpus chaplasha and Cassia siamea. These observations suggest that both the physico-chemical properties of soil play a major role in shaping the tree distribution in KNP. Hence, these soil properties should take into account for any tree conservation strategy in this forest.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.25 no.5
• /
• pp.59-76
• /
• 2022

This study was conducted to investigated woody species community classification and understory vegetation characteristics of Abies nephrolepis forest in Mt. Gyebang and Mt. Odae designated as Protected Area for Forest Genetic Resource Conservation and National Park. Vascular plants were surveyed as following; 55 family, 148 species, 3 sub species, 14 variety, 2 form 167 taxa. As an analysis of the species estimator of Jackknife 1, 29 survey plots could be representative of vegetation in study site. Results of the woody species, 3 communities were divided by cluster analysis(A=Abies nephrolepis-Tilia amurensis, B=Betula ermanii-Abies nephrolepis, C=Quercus mongolica-Abies nephrolepis). Using MRPP-test, there were significant differences between the communities indicating analysis of the appropriate group classification(p<0.01). The basal area and altitude were analyzed by negative relationship for NMS ordination. By analyzing plexus diagram of woody species, Acer pseudosieboldianum is strong associated with Quercus mongolica and Rhododendron schlippenbachii. Magnolia sieboldii is strong associated with Acer pictum subsp. mono etc.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.55 no.5
• /
• pp.590-597
• /
• 2022

We analyzed the diet composition of smallmouth argentine Argentina kagoshimae, which were collected via bottom trawl in the South Sea during February, April, August, and October 2021. Their size range was 8.1-21.4 cm total length. A. kagoshimae are mesopelagic carnivores, mainly consuming benthopelagic Euphausiacea and Caridea crustaceans. Polychaetes were the second largest prey component in their diet, which also included small quantities of copepods, amphipods, and arrow worms. Stomach content compositions substantially differed among body size levels in A. kagoshimae. The results of non-metric multidimensional scaling ordination and permutational multivariate analysis of variance of dietary data revealed no significant dietary differences. The results of a graphical analysis of the diet composition showed that A. kagoshimae are specialized feeders characterized by strong individual feeding specialization.

• Journal of the Korean Geotechnical Society
• /
• v.23 no.3
• /
• pp.77-88
• /
• 2007

A micromechanics-based model to simulate the elastic and elastic-plastic behavior of granular soils is developed. The model accounts for the fabric anisotropy represented by the statistical parameter of the spatial distribution of contact normals, the evolution of fabric anisotropy as a function of stress ratio, the continuous change of the co-ordination number relating to the void ratio, and the elastic and elastic-plastic microscopic contact stiffness. Using the experimental data for metallic materials, the elastic-plastic contact stiffness is derived as a power function of the normal contact force as well as the contact force initiating the yielding of contact bodies. To quantitatively assess microscopic model parameters, approximate solutions of cross-anisotropic elastic moduli are derived in terms of the micromechanical parameters.

• Korean Journal of Environment and Ecology
• /
• v.37 no.5
• /
• pp.347-366
• /
• 2023

In the present study, the vegetation was classified using the phytosociological method and canonical-correlation analysis (CCA) was implemented to analyze correlation between community structure and environmental factors in the natural habitats of forest byproducts, especially medicinal plants, such as Cudrania tricuspidata, Sorbus commixta, and Hovenia dulcis, in 2021-2022 to provide primary ecological data to establish environmental conditions for wild vegetable cultivation. A total of 11 plots in five regions, 8 plots in three regions, and 17 plots in 5 regions were selected for the natural habitats of C. tricuspidata in southern Korea, S. commixta in high mountains, and H. dulcis in valleys of central Korea, respectively. The importance value in each community was respectively analyzed as follows, in C. tricuspidata community, the importance value of C. tricuspidata (61.10) was the highest, followed by Celtis sinensis, Pinus thunbergii, Neolitsea aciculata, Styrax japonica, Carpinus coreana, Quercus serrata, and Q. acutissima. In Sorbus commixta community, Q. mongolica (57.21) was the highest, followed by, S. commixta (42.58), Betula ermani, Tilia amurensis, A. pseudosieboldianum, A. tschonoskii var. rubripes, Cornus controversa, Magnolia sieboldii, and Taxus cuspidata. In H. dulcis community, H. dulcis (64.58) was the highest, followed by Zelkova serrata, Cornus controversa, A. mono, Q. serrata, C. cordata, and Juglans mandshurica. As the result of the analysis on DBH of the major species having the high importance value, in C. tricuspidata community, C. tricuspidata, C. sinensis, Neolitsea aciculata, and C. coreana show the density of normal distribution, so the dominant status of these species is likely to continue. In S. commixta community, S. commixta show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and Q. mongolica, B. ermani and T. amurensis, show the density of normal distribution, so the dominant status of these species is likely to continue. In H. dulcis community, C. cordata, and J. mandshurica show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and H. dulcis, Z. serrata, C. controversa and A. mono had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. The results of CCA ordination analysis using 11 environmental factors and 30 communities of three taxa classified by TWINSPAN analysis revealed that the altitude showed the strongest correlation with the vegetation. C. tricuspidata community was distributed on the moderate and gentle northeastern slope at low altitude with the highest pH, C.E.C, Ca²⁺, and Mg² and various P₂O₅, whereas S. commixta community was distributed on the steep slope at high altitude with the highest O.M and T-N and lower P₂O₅, Ca²⁺, Mg²⁺, C.E.C and pH, which is the opposite tendency of the environment of C. tricuspidata community. H. dulcis community was distributed on the gentle northern slope at lower altitude with an average pH, O.M, T-N, Ca²⁺, Mg²⁺, and C.E.C, except higher P₂O₅.

• Korean Journal of Environment and Ecology
• /
• v.21 no.4
• /
• pp.318-335
• /
• 2007

Floral study and present vegetation survey were conducted at a representative reclaimed wetland located behind the Rural Research Institute at Ansan, Gyeonggi-do. The importance values were calculated from the ground cover and frequency of recorded species within quadrats and detrended canonical correspondence analysis was conducted using environment variables, such as total nitrogen, electric conductivity, available phosphate, nitrate nitrogen and the distance from the inner roads. And basal areas for the trees encroaching on the reclaimed wetland were estimated to take a look at the on-going situation about the succession routes on land. As a result, 46 families and 158 species of plants were recorded and Pragmites communis was found to be a dominant species as the present vegetation. The ordination analysis results showed that species distribution was purposely explained by total nitrogen in soil and its content in nitrate nitrogen. The invasion of Robinia pseudoacacia and Pinus rigida whose basal areas were $22.3m^2$ and $1.6m^2$ respectively, into the interior areas of the reclaimed wetland was found to cause a disturbance making some parts of the wetland into land. The zoning program using water level control and migratory roads is becoming a contributing factor in destroying a wetland, so it's suggested that some adjustments should be needed to take care of it.

• Journal of Ecology and Environment
• /
• v.38 no.4
• /
• pp.405-413
• /
• 2015

We classified the streamside plant community by phyto-sociological method and analyzed the relationship between environment factors and vegetation structure by using the classification and ordination method. We found that twenty one plant communities were classified according to dominant species at the natural streamside valley forest with surveying the 65 quadrats (10 m × 10 m). From the survey results, the hardwood plant communities were classified as streamside valley forest and the softwood plant communities as riparian forest according to the degree of flooding. The valley forest had a distribution of 17 plant communities which was 65% (42 quadrats) of 65 quadrats: Maackia amurensis community, Betula davurica community, Quercus variabilis community, Pinus densiflora community, Q. serrata community, Prunus sargentii community, and Meliosma oldhamii community etc. The riparian forest had a distribution of four plant communities which was 35% (23 quadrats) of 65 quadrats: Salix koreensis community, S. rorida community, S. purpurea var. japonica community, and S. glandulosa community, etc. From the two-way indicator species analysis (TWINSPAN) analysis, we found indicator species Oplismenus undulatifolius and Lindera obtusiloba for the streamside valley forest and Humulus japonicus, Phragmites japonica, and S. koreensis for the riparian forest. From the results of the canonical correspondence analysis (CCA), coordinates, altitude, and stream structure showed low correlation to the distribution of the plant community. Therefore, it seemed that valley forest and riparian forest were distinguished by the stream gradient and waterway width which determined by the stream water level.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.6
• /
• pp.38-48
• /
• 2008

This study was conducted to evaluate the vegetation structure of community by the phytosociology method, floristic composition table on coast of South Korea. Form 2007 June until November, $2m{\times}2m$ quadrat was established in native Glehnia littoralis in order to record a dominants and coverage, and it drew the profile. It was found out that the mean temperature in the distributed areas for Glehnia littoralis population was $11^{\circ}C$ or more. The flora of the studied area in Glehnia lottoralis community of coastal dune was listed as 100 species. Glehnia lottoralis community of appearance species of Yeonggwanggun Duwori was many most by 44 species. Carex pumila, Carex Kobomugi, Imperata cylindrica var. koenigii, Ischaemum anthephehoroides and Vitex rotundifolia range all over the studied areas. And the vegetation of Glehnia littoralis community was classified into Vitex rotundifolia subcommunity, Ischaemun anthephephoroides subcommunity and Imperata cylindrica var. koenigii subcommunity. Native Glehnia littoralis was classified into preserve area, natural selection area and artificial destruction area. It must preserve native Glehnia littoralis of Goseong, Yeongdeok, Haenam it was ecological important area.