臺灣東北部柳杉人工林土壤有機碳儲量的推估

Estimation of Soil Organic Carbon Storage in a Cryptomeria Plantation Forest of Northeastern Taiwan

張瑀芳(Yu-Fang Chang) ； 林世宗(Shu-Tzong Lin) ； 蔡呈奇(Chen-Chi Tsai)

《台灣林業科學》 21卷4期 (2006/12) Pp. 383-393

https://doi.org/10.7075/TJFS.200612.0383

摘要

本研究以人工針葉林中材積蓄積量最高的柳杉做為研究的對象，在51年生之柳杉人工林下選擇3個代表性土壤樣體與在4個試驗樣區（大小為20×25m）內隨機選擇三處採樣點，分層（0~10、10~20與20~30cm）採集土壤樣本，以推估柳杉人工林下土壤有機碳的貯存量。研究結果指出：受到地形因子坡度的影響，三個代表性土壤樣體之A層、E層與土壤樣體之厚度皆較淺；受土壤母質影響，土壤質地較細，為坋質黏壤土或坋質黏土。研究區內3個代表性土壤樣體，1個分類為極育土(Ultisols)，2個分類為淋澱土(Spodosols)。極育土土壤表層30cm內之有機碳貯存量為8.56kg m^(-2)，而淋澱土土壤表層30cm內之有機碳貯存量平均為14.0kg m^(-2)。本研究之土壤剖面中的有機碳貯存量較低於前人研究的結果，可能是由於樣品數較少、環境的差異、取樣方式的不同、土壤類型與植被類型的差異、土壤有機碳含量的空間變異較大等因素所造成。另外，試驗樣區的分析結果，平均而言本研究區之柳杉人工林地下部土壤碳貯存量(0~30cm)約為127 tons ha^(-1)，其中0~10cm土層中所貯存的土壤有機碳含量佔有57%（約72 tons ha^(-1)），10~20cm土層佔有26%（約為34 tons ha^(-1)），而20~30cm土層僅佔有17%（約21 tons ha^(-1)）。

關鍵字

柳杉人工林 ； 土壤有機碳 ； 碳貯存量 ； 極育土 ； 淋澱土

並列摘要

Cryptomeria japonica (L. f.) D. Don in a plantation forest was selected as the research species because it contains the highest storage volume of wood among coniferous plantations in Taiwan. The objective of this study was to evaluate the soil organic carbon (SOC) storage in a Cryptomeria plantation forest. Three representative soil pedons and 4 experimental plots (20×25m) were selected in a 51-yr-old Cryptomeria plantation forest of northeastern Taiwan. The results of this study indicated that the A, E, and solum thicknesses of 3 representative soil pedons are shallow because of the effects of steep soil slopes. The parent material also has a great effect on the soil texture and here resulted in fine-textured soils (e.g., silty clay loam or silty clay). The 3 representative soils were classified as Ultisols and Spodosols. The SOC storage of Ultisols was 8.56kg m^(-2), and in Spodosols was 14.0kg m^(-2) (on average). The results of the lower SOC storage in these study soils could be attributed to the small sample number; to different soil formation environments, soil sampling methods, soil types, and vegetation types; and to a higher spatial variability of SOC. Further, the evaluation results of the 4 experimental plots showed that, on average, SOC stored in the surface soil (0~30cm) was about 127 tons ha^(-1). Cumulatively, 57% (72 tons ha^(-1)) of the total organic carbon to a depth of 30cm was stored at 0~10cm, 26% (34 tons ha^(-1)) at 10~20cm, and 17% (21 tons ha^(-1)) at 20~30cm.

並列關鍵字

Cryptomeria japonica plantation forest ； soil organic carbon ； carbon pool ； Ultisols ； Spodosols