Wood Carbon Content and Basic Density of Taiwan Red Cypress (Chamaecyparis formosensis) Trees Grown under Different Thinning Treatments in the Liouguei Area

六龜地區不同疏伐處理紅檜造林木的木材碳含量及基本密度

邱志明(Chih-Ming Chiu) ； 林振榮(Cheng-Jung Lin)

《台灣林業科學》 25卷3期 (2010/09) Pp. 201-209

https://doi.org/10.7075/TJFS.201009.0201

摘要

為了正確評估森林中碳吸存量，瞭解木材碳含量及基本密度是重要的，本報告調查不同疏伐處理紅檜(Chamaecyparis formosensis)造林木對木材碳含量及基本密度的影響，結果顯示紅檜造林木的木材碳含量，在不同疏伐處理中並沒有顯著差異性存在，然而，強度疏伐處理（斷面積為30 平方公尺 ha^(-1)）比中度、弱度及沒有疏伐處理的紅檜造林木有較低的基本密度，而紅檜木材碳含量及基本密度，在不同樹齡中有顯著差異性存在。
樹輪特徵值對紅檜木材碳含量的影響經過檢測分析發現，木材碳含量隨著樹輪寬度參數的增加而增大，但是，隨著樹輪密度參數的增大而降低的結果，不同的樹輪特徵值會影響木材碳含量，其中，晚材寬度及晚材率是最重要的影響因素。本報告結果得知紅檜造林木木材碳含量及基本密度在適當疏伐（中度）以下的林分密度中沒有差異，因此，對於計算碳吸存量沒有影響，但是在不同樹齡時則會有影響而需要考慮樹齡變數。

關鍵字

疏伐 ； 紅檜 ； 木材碳含量 ； 木材基本密度

並列摘要

Understanding the wood carbon content and basic density is important for accurately assessing forest carbon sequestration. The effects of different thinning treatments on the wood carbon content and basic density of Taiwan red cypress (Chamaecyparis formosensis) trees were investigated. The results revealed that the average wood carbon contents under different thinning treatments showed no statistically significant differences. However, trees from heavily thinned plantations (basal area, 30 m^2 ha^(-1)) had lower wood basic density than those from plantations with medium, light, and no thinning. Significant differences in the wood carbon content and basic density were observed among cambium of various ages.
The effects of ring characteristics on the wood carbon content of Taiwan red cypress were examined. The wood carbon content increased with increasing ring width parameters and decreasing ring density parameters. In our analyses, the carbon content was affected by various ring characteristics; moreover, both the latewood width and latewood percentage in a ring were the best predictors. The results suggest that using a moderate (≤ medium thinning) plantation density will have no effects on the wood carbon content or wood basic density; however, different tree ages should be considered for calculating carbon sequestration.

並列關鍵字

thinning ； Taiwan red cypress ； wood carbon content ； wood basic density