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 5㎝. In addition, several environmental factors such as field soil pH, field soil moisture, soil compressibility, depth of soil, thichness of litter layer, elevation and basal area were measured. Thress soil cores were sampled and various physical and chemical 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: coiferous, 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 A_1 horizon decreased from the coniferous to broad leaved foreast, while maximum field capacity, pore space, exchangeable cations, loss on ignition, soil pH and 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 densiflora→Quercus monglica, Q. serrata, Q. aliena→Carpinus laxiflora→C. 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 effect of the sampling errors on ordination perfermance, this low heterogeneity seems to cause the poor concentation of the total variance. The results from the four kinds of ordination were in good aggrement 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.
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