- 期刊
光蠟樹人工林碳貯存量和吸存量之估算
Estimate of Carbon Storage and Sequestration of Fraxinus Griffithii Plantations in Taiwan
摘要
光蠟樹(Fraxinus griffithii C. B. Clarke)是台灣原生種，為台灣最重要的闊葉樹造林樹種之一。本研究以林業試驗所轄區內，位於六龜和太麻里試驗林的兩處光蠟樹人工林為對象，估算其造林木之生物量和生長量，建立根莖比和材積生物量轉換係數等參數和迴歸式，並估算其碳貯存量和吸存量。光蠟樹材積地上部生物量轉換係數，六龜林分為1.14Mg m^(-3)，高於太麻里林分的0.89Mg m^(-3)；根莖比則分別為0.235和0.233，兩林分相近。兩林分材積連年生長和平均生長曲線皆隨年齡而呈上升趨勢，但尚未相交。經估算，六龜林分光蠟樹地上部生物量為121Mg ha^(-1)，高於太麻里林分的114Mg ha^(-1)。光蠟樹林分全部植物地上部生物量達163-199Mg ha^(-1)，不低於台灣年齡相近的闊葉樹人工林。經分析光蠟樹植體的碳濃度為48.3-50.9%。以光蠟樹全株林木碳吸存量推估，六龜林分光蠟樹平均可吸存碳2.58Mg ha^(-1) yr^(-1)，即吸存9.47Mg ha^(-1) yr^(-1) CO2；太麻里林分則為1.93Mg ha^(-1) yr^(-1)，即吸存7.08Mg ha^(-1) yr^(-1) CO2，大致上與台灣主要闊葉樹造林樹種全株碳吸存量相近，但低於熱帶地區闊葉人工林如桉樹等的碳吸存量。以整個生態系而言，兩林分碳貯存量，六龜林分為175Mg ha^(-1)，太麻里林分為230Mg ha^(-1)，土壤分別佔生態系碳貯存量的44.7%和47.7%，在生態系碳貯存量上扮演主要角色。
並列摘要
Fraxinus griffithii C. B. Clarke, a native species, is one of the most important planted broadleaf species in Taiwan. Two stands of the Fraxinus griffithii plantations in the Liouguei and Taimalee experimental forests of Taiwan Forestry Research Institute located in south and southeast Taiwan, respectively, were studied in order to estimate biomass and growth of planted trees and to build parameters such as root/shoot ratios and conversion coefficients and allometric equations. Then C distributions of whole ecosystem were calculated and C sequestrations of planted trees were estimated as well. The conversion coefficient from volume to aboveground biomass calculated from the means of the sample trees at the Liouguei stand was 1.14 Mg m^(-3), which was slightly higher than that of Taimalee stand (0.89 Mg m^(-3)). The estimated root/shoot ratios, 0.235 and 0.233 for the planted trees in the Liouguei and Taimalee stands, respectively, were similar at both stands. Curves of current and mean annual increment for volume in both stands rose with age and did not cross in both stands yet. The estimated aboveground biomass was 121 Mg ha^(-1) for the planted trees at the Liouguei stand, which was higher than that of the trees at the Taimalee stand, 114 Mg ha^(-1). The total aboveground biomass of all plants for the plantations ranged 163-199 Mg ha^(-1), which was equal or higher than that of broadleaf plantations with similar age in Taiwan. The ranges of C concentrations among components were 48.3-50.9% for the planted trees in both stands. The mean C absorption of entire planted trees were 2.58 Mg ha^(-1) yr^(-1) and 1.93 Mg ha^(-1) yr^(-1) for the Liouguei and Taimalee stands, respectively, which means 9.47 and 7.08 Mg ha^(-1) yr^(-1) of CO2 to be absorbed by the entire planted trees of the Liouguei and Taimalee stands, respectively. Those were lower than that of broadleaf plantations such as Eucalyptus in the tropics. The C storages of whole ecosystem were 175 and 230 Mg ha^(-1) for the Liouguei and Taimalee stands, respectively. Soil, which contained 44.7 and 47.7% of C stored in the ecosystem of the Liouguei and Taimalee stands, respectively, plays an important role for C storages in the plantation ecosystems.