杉木人工林生長量與碳吸存之研究

Abstract

本研究旨在探討杉木人工林生長收穫及生物量與碳吸存之相關問題，其內容包括林分直徑分布、單株林木之生長模擬、各部位生物量與胸徑之關係及其隨時間之變化、不同部位碳含量與碳氮比之分析及相關關係式之建立，由以上所得之資料，提供森林經營具體之資訊。研究之試驗地位於八仙山事業區十文溪示範區內之杉木造林地，因該區域已屆伐期齡，冀由單木生長為基礎，探討林分之生長，以供全林應用。 研究所得主要結果分述如下： 以三參數之Weibull機率密度函數模擬杉木林分之直徑分布，與以Richards模式模擬單木之胸高斷面積與材積生長，皆獲得良好之結果。由於樹高生長並無法找到明顯的反曲點，故以Mitscherlich模式模擬之。顯示不同性態值之生長特性應選擇不同型態的模式來加以模擬。 杉木單木之枝部、幹部與地上部乾重皆隨胸徑增大而增加。就其現存生物量所佔之百分率而言，葉部及枝部生物量隨著林齡之增加，其所佔之比例逐漸下降，而幹部生物量所佔之比例，則隨林齡之增大而增高。 林木內所含之碳含量在不同直徑級與幹部、枝部、葉部等不同部位間均具顯著差異，此顯示於推估林木之碳含量時，須將各部位分開測計，不宜合併討論。 以上研究所得之結果，可提供杉木人工林經營詳盡之資訊，做為經營決策之重要參考依據。

This study discuss about the problem within timber management, biomass and carbon sequestration of Cunninghamia lanceolata plantation. The content include diameter distribution, simulation individual tree growth model, the relationship between biomass and D.B.H., Carbon content of different position and the analysis of C/N and create an interrelated function. This data can provide with concrete information for forest management . Data of this study were collected from China-fir plantation on Pa-Hsien-Shan working circle and Shyr-Wen-Shi demonstration zone. The stand is arrived at rotation age, and we hope to understand the growth of stand by the individual tree's data. The summary of obtained result is as follows : Diameter distribution of China-fir plantation is fitted by three-parameter Weibull distribution. Basal area growth and volume growth is fitted by Richards growth model.We used Mitscherlich to fit height growth. It means that basal area growth, volume growth and height growth should choose different kinds of model to simulation. The dry weight of branch, stem, and above-ground all increase with DBH. The proportion of the biomass of branch and leaf is decreased with the increase in age, but the opposite is true for the biomass of stem. Carbon sequestration on different diameter and different portion all have significance, it means that when estimate the carbon sequestration in stand, stem, branch and leaf should calculate individually. The results will provide detailed information for China-fir plantation.