紅檜和台灣杉人工林單木直徑生長與枯死模式之研究

Individual Tree Diameter Growth and Mortality Models for Chamaecyparis formosensis and Taiwania cryptomerioides Plantations

陳鈺惠(Yu-Hui Chen) ； 楊銘鑫(Ming-Xin Yang) ； 王兆桓(Chao-Huan Wang)

《宜蘭大學生物資源學刊》 6卷1期 (2010/12) Pp. 71-77

https://doi.org/10.6175/job.2010.61.18

摘要

在林分發展過程中生長和枯死是重要因子，本研究選用紅檜人工林與台灣杉人工林建立紅檜與台灣杉的單木直徑生長及枯死模式。資料以林務局森林永久樣區複測的調查資料。自變數為胸高直徑、林分斷面積、大於目標林木的斷面積合計值、活冠比、地位指數、平均優勢木樹高等。生長模式的應變數為胸高直徑生長量，使用SAS統計軟體的NLIN程式分析。枯死模式的應變數為死亡與存活，使用SAS統計軟體的Logistic程式分析，並以其卡方檢定（χ^2）與AIC值進行自變數的篩選。在目前的資料中，有些樣區缺乏造林年度，所以使用平均優勢木樹高來代替地位指數。結果顯示在紅檜的單木直徑生長模式中D、SI（或Hd）、CR、BAL、BA具有影響。在台灣杉的單木直徑生長模式中D、Hd、CR、BAL、BA具有影響。在紅檜的單木枯死模式中D、D^2、SI（或Hd）、BAL、CR具有影響。在台灣杉的單木枯死模式中D、CR、SI（或Hd）具有影響。當缺少造林年度時，可使用平均優勢木樹高建立單木直徑生長模式和枯死模式。

關鍵字

單木模式 ； Logistic模式 ； 直徑生長

並列摘要

The model in forest development and harvesting is needed to contain growth and death, Equations are presented to construct individual diameter growth and mortality models for Chamaecyparis formosensis and Taiwania cryptomerioides plantations using the first and the second survey data from Taiwan Forestry Bureau permanent plots. The independent variables are diameter at breast height (DBH), site index (SI), crown ratio (CR), stand basal area (BA), stand basal area in trees larger than subject tree (BAL) and the average dominant tree height (Hd). The dependent variable of the diameter growth model is the diameter growth, using the SAS Proc NUN for analysis. The dependent variable of the mortality model is a binomial variable for survival and death, using the SAS Proc Logistic for analysis, and its chi-square test (χ^2) and the AIC value for the independent variables selection. Not all of the plots have the planting year records, so the average dominant tree height is used to replace the site index to establish both models. The results of fitting diameter growth models show that D, SI (or Hd), CR, BAL and BA are significantly effecting diameter increment of trees in Chamaecyparis formosensis plantation; D, Hd, CR, BAL and BA are significantly effecting diameter increment of trees in Taiwania cryptomerioides plantation. The results of fitting mortality models show that D, D^2, CR, SI (or Hd) and BAL have significant impact the tree mortality rate in Chamaecyparis formosensis plantation; D, CR and SI (or Hd) have significant impact the tree mortality rate in Taiwania cryptomerioides plantation. When the lack of the planting year record, we can use Hd instead of SI to establish both models.

並列關鍵字

individual tree model ； Logistic model ； diameter growth