Journal of Korean Society of Forest Science (한국산림과학회지)

Korean Society of Forest Science (한국산림과학회)
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Localizing Growth Model of Chamaecyparis obtusa Stands Using Dummy Variables in a Single Equation

  • Lee, Sang-Hyun (Faculty of Forest Science, College of Agriculture & Life Sciences, Chonbuk National University) ;
  • Kim, Hyun (Faculty of Forest Science, College of Agriculture & Life Sciences, Chonbuk National University)
  • Received : 2005.03.11
  • Accepted : 2005.04.13
  • Published : 2005.04.30
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Abstract

This study was carried out to construct a single diameter and a single height model that could localize Chamaecyparis obtusa stand grown in 3 Southern regions of Korea. Dummy variables, which convert qualitative information such as geographical regions into quantitative information by means of a coding scheme (0 or 1), were used to localize growth models. In results, modified form of Gompertz equation, $Y_2={\exp}({\ln}(Y_1){\exp}(-{\beta}(T_2-T_1)+{\gamma}({T_2}^2-{T_1}^2))+({\alpha}+{\alpha}_1Al+{\beta}_1k_1+{\beta}_2k_2)(1-{\exp}(-{\beta}(T_2-T_1)+{\gamma}({T_2}^2-{T_1}^2))$, for diameter and height was successfully disaggregated to provide different projection equation for each of the 3 regions individually. The use of dummy variables on a single equation, therefore, provides potential capabilities for testing the justification of having different models for different sub-populations, where a number of site variables such as altitude, annual rainfall and soil type can be considered as possible variables to explain growth variation across regions.

Keywords

Acknowledgement

Supported by : Korea Science & Engineering Foundation

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