• Korean Journal of Ecology and Environment
• /
• v.41 no.spc
• /
• pp.1-10
• /
• 2008

We patterned water quality of agricultural reservoirs according to the differences of six physico-chemical environmental factors (TN, TP, DO, BOD, COD, and SS) using four different ordination methods: Principal Components Analysis (PCA), Detrended Correspondence Analysis (DCA), Nonmetric Multidimensional Scaling (NMS), and Isometric Feature Mapping (Isomap). The data set was obtained from the water quality monitoring networks operated by the Ministry of Agriculture and Forestry and the Ministry of Environments. Chlorophyll-${\alpha}$ displayed the highest correlation with COD, followed by TP, BOD, SS, and TN (p<0.01), while negatively correlated with altitude and bank height of the reservoirs (p<0.01). Although four different ordination methods similarly patterned the reservoirs according to the gradient of nutrient concentration, PCA and NMS appeared to be the most efficient methods to pattern water quality of reservoirs based on the explanation power. Considering variable scores in the ordination map, the concentration of nutrients was positively correlated with Chl-${\alpha}$, while negatively correlated with altitude and bank height. These ordination methods may help to pattern agricultural reservoirs according to their water quality characteristics.

• Korean Journal of Environment and Ecology
• /
• v.3 no.1
• /
• pp.28-41
• /
• 1989

A survey of Hongryu-Dong and Chi-in district. Gaya National Park, was conducted using 40 sample sites of 500$m^2$ size. TWINSPAN classification confirmed a complex pattern of both local and geographical variation in the vegetation: Dry and wet community types. Within dry community types, two floristic assocation of Pinus densiflora were defined according to local variation. Within wet community types. two floristic association were defined according to altitude. Those associations can be further subdivided floristically into eight subassociation. The vegetation pattern presented by DCA ordination corresponds to one of TWINSPAN at the first two division. The DCA ordination was successful in separating Pinus densiflora from broad leaf forest. Ordination of samples produced arrangements reflectly environmental gradient of soil. The correlation between the first axe of DCA and soil moisture, soil acid, altitude, maximum species diversity and species diversity was significantly negative. The similarity index between each community was very low level.

• Journal of Plant Biology
• /
• v.25 no.2
• /
• pp.83-99
• /
• 1982

In this study, thirty-two stands in Kwangnung forest located in the central part of Korea were preferentially selected. In each stand, all stems for trees and shrubs were recorded by species and their girths were measured down to 5cm. In addition, several enviromental factors such as field soil pH, field soil moisture, soil compressibility, depth of soil, thickness of litter layer, elevation and basal area were measured. Three soil cores were sampled and various physical and chemcial properties was determined. The vegetational data were subjected to three kinds of multivariate ordination(PO, PCA, RA). The results suggested that Kwangnung forest was consisted of three forest types: coniferous, mixed and broad leaved forest communities. The relation between the stand scores of ordination and several environmental factors were investigated in terms of correlation analysis in order to examine the relationships between the vegetation and certain environmental factors. As a result of this analysis, the amount of sand content in A1 horizon decreased frm the coniferous to broad leaved forest, while maximum field capacity, pore space, exchangeable cations, loss on ignition, soil pH nad the amount of total nitrogen had a tendancy to increase significantly. However, easily soluble phosphorus appeared to have little to do with the forest types. The result of species ordination of centered-standardized PCA suggested that the major successional pathway in Kwangnung forest was; Pinus densifloralongrightarrowQuercus mongolica, Q. serrata, Q. alienalongrightarrowCarpinus laxifloralongrightarrowC. erosa in sequence. This trend is in good agreement with the past studies. In three kinds of ordination (centered PCA, centered-standardized PCA and RA) based on nineteen species and twenty-five stands, the total variances accounted for the first three axes were 77%, 46% and 63% respectively. The estimated beta diversity in Kwangnung forest assumed as a coenocline, was 1.5~1.8 HC. Increasing the effect of the sampling errors on ordination perfermance, this low heterogeneity seems to cause the poor concentration of the total variance. The results from the four kinds of ordination were in good agreement with each other, especially between PO, centered-standardized PCA and RA appeared robust. It seems to be worthy of applying multivariate method for analyzing other forest communities in Korea.

• Journal of Korean Society of Forest Science
• /
• v.77 no.1
• /
• pp.73-82
• /
• 1988

This study was excuted to analyze the vegetational community structure of the Hongrudong valley the Mt. Gaya by three kinds of ordination techniques (polar, principal component analysis, reciprocal averaging). Eleven sites were sampled with the clumped method to analyze the vegetation structure. The result suggested that Hongrudong valley forest was divided by Pinus densiflora and Quercus aliena community. The relation between stand scores of ordination and soil pH, humus content, soil moisture had a tendency to increase significantly from P. densiflora to Q. aliena community. RA was the most effective method of this study. RA ordination was showed that successional trends of tree species seem to be from P. densijlora through Q. variabilis to Q. aliena, Carpinus laxiflora in the upper layer and from Lespedeza cyrtobotrva, Rhus spp., Rhododendron schlippenbachii through Fraxinus sieboldiana, Lindera obtusiloba to Euonymus oxyphyllus, Weigela subsessilis, Callicarpa japonica in the middle layer.

• The Korean Journal of Ecology
• /
• v.15 no.2
• /
• pp.117-125
• /
• 1992

TWINSPAN(two-way indicator species analysis), DCCA(detrended canonical correspondence analysis) and polar ordination method wee used so as to analyze the the relation between forest vegetation and hibitat of mudungsan(1, 187m) located in kwangju area. Vegetationsurvey consulted 1:25, 000 topographical map, set up 41 quadrats and analyzed from April, 1990 to August, 1991. Forest vegetation of mudungsan was classifild to quercus acutissima community, fraxinus mandshurica community, quercus mongolica community, quercus serrata community, quercus dentata community, quercus variabilis community, and pinus densiflora community by TWINSPANmethod, and this almost coincide with the result of plar ordination. according to DCCA analysis, P. densiflora community was formed in xeric and low altitude region which soil nutrient was poor, compared with other communities. q. variabilis and q. acutissima community wee distributed in the region that low altitude and organic matter content was comparatively low, but q. acutissima community was formed in a damp region while q. variabilis community in a xeric region. q. mongolica and f. mandshurica formed the communities in a high altitude region, especially f. mandshurica cmmunity was distributed in a high humidity region. According to polar ordination analysis, the forest vegetation was classified to 7 communities by means of environmental gradient such as humidity, organic matter, ph, temperature, c.e.c and P2O5.

• The Korean Journal of Applied Statistics
• /
• v.28 no.1
• /
• pp.49-60
• /
• 2015

Various kinds of ordination methods such as correspondence analysis and canonical correspondence analysis are used in community ecology to visualize relationships among species, sites, and environmental variables. Ter Braak (1986), Jackson and Somers (1991), Parmer (1993), compared the ordination methods using eigenvalue and distance graph. However, these methods did not show the relationship between population and biplot because they are only based on surveyed data. In this paper, a method that measures the extent to show population information to biplot was introduced to compare ordination methods objectively.

• Journal of Environmental Science International
• /
• v.32 no.5
• /
• pp.329-341
• /
• 2023

We surveyed the vegetation of an ecological landscape preservation area (legally protected conservation areas or national parks) and the surrounding areas of Mt. Cheonggye, Republic of Korea, to explore the conservation implications for preservation areas and surrounding transition areas. We calculated diversity indices to identify the properties of the preservation and surrounding areas that are relevant to conservation efforts. We then compared the plant community composition between the areas using field and quadrat surveys in the preservation and surrounding areas. The cover of the dominant species in all tree and herb layers was markedly higher in the preservation area than in the peripheral zones. The species richness indices were significantly higher in the preservation area than in the peripheral zones. Ordination using detrended canonical correspondence analyses showed that the cover of the dominant tree species and rocks could explain the distribution of plant species in the Cartesian space of the ordination. Our results demonstrate that physiognomically designated protected areas match well with ecological data based on diversity indices and ordination analyses and that disturbances in the areas surrounding the ecological landscape of preservation areas can have considerable impacts on plant diversity indices. Hence, the preservation and management of surrounding areas are essential conservation elements for protecting the entire ecological landscape of preservation areas.

• The Korean Journal of Ecology
• /
• v.21 no.3
• /
• pp.291-300
• /
• 1998

The forest vegetation of Mt. Odae based on the interspecific relationship was classified into 4 groups : Quercus mongolica, Pinus densiflora, Quercus variabilis and Patrinia saniculaefolia. Thirty-one species of Quercus mongolica group including Quercus mongolica and Acer mone, 12 species of Pinus densiflora group comprising Pinus densiflora and Spodiopogon sibiricus, 6 species of Quercus variabilis group and 4 species of Patrinia saniculaefolia were positively correlated. in the results of species ordination by principal component analysis, 7 clusters by the humidity and acidity of soil, 4 clusters by the humidity and light intensity and 7 clusters by the acidity and light intensity were formed. The plot ordination showed that the distribution of species based on the humidity, soil acidity and total organic matters was in the order of Pinus densiflora, Quercus variabilis and Quercus mongolica groups, and based on the light intensity was in the order of Quercus variabilis, Pinus densiflora and Quercus mongolica groups.

• International Journal of Contents
• /
• v.8 no.3
• /
• pp.42-51
• /
• 2012

Korea has entered into the Post Catching-up era and the necessity of new innovation strategy in response is being raised. This study argues the necessity of new innovation strategy and discusses the issue of co-ordination between R&D and Human Resource for that as the key factor. From empirical analysis, there seems to be restricted inflow of outstanding human resources to manufacturing sectors and lowering effectiveness of major even with the improved compatibility between major and job. Especially, it is severe in the industries with high R&D investment. It can be interpreted as an incoordination of the technological innovation efforts from the aspect of R&D investment with human resource utilization from the aspect of new human resource. The analytical result and interpretation suggests that there should be more active improvement on the co-ordination between innovative manufacturers' efforts and human resource utilization, in order to keep sustainable development.

• Korean Journal of Weed Science
• /
• v.2 no.2
• /
• pp.129-140
• /
• 1982

Herbicides were classified by two-dimensional ordination analysis based on the weed flora which was not controlled by application of a particular herbicide. The number of herbicide group was varied depending upon the weed community type and the experiment site. The technique of the two-dimensional ordination analysis gave more comprehensive informations about selecting of herbicides for increasing the herbicidal efficacy, for increasing the weed spectrum and for reducing the herbicide cost by mixing of herbicides. The two-dimensional ordination analysis could be used not only herbicide classification and selecting effective herbicide or herbicide combination but also can be used for the evaluation of systematic application of herbicides.