DBH-Growth Model by Competition Index for Pinus koraiensis.
Woo-Kyun Lee• Jeong-Ho Seo• Jae-Woo Hwang• Zin-Su Kim

 

ABSTRACT : In this study, the relationship between competition index and tree-ring growth was analyzed and dbh growth model was prepared for Pinus koraiensis stands in Gapyoung-Gun, Korea. An annual radtal growth model was prepared by analyzing the relationship between dbh and competition mdex of individual trees. Annual radtal growth was employed as a dependent parameter in this model. Age and height of dominant tree. which estimate site quality. dbh and Hegyi's competition index of individual trees were employed as independent parameters. Several non-linear regression equations composed of above parameters were analyzed and following annual radial growth model(Rh) for individual trees was prepared : The coefficient of determination was 0.57. It comctded with a general growth principles that dbh of indivtdual trees and height of the dominant tree had a positive effect on radial growth, and increase of age and competition index restrained radial growth. In general, height of the dominant tree was estimated from dbh of the dominant tree using the hight-dbh curve equation. There was a positive correlation between these two factors, so a new annual radial growth model(R.t'). in which height of the dominant tree was substituted
for dbh of the dominant tree(dc), was prepared. This new model in whtch dbh of dominant tree was employed as an independent parameter was also coincided with the general growth principles. The dbh-growth for n years could be estimated by following equation which conststs of the dbh at the present time and the sum of annual radial growth for n years.

Key words: competition index, tree-ring growth, Pmus koraiensis, annual radial growth model, dbh-growth model