Comparison of Soil CO2 Efflux from a Secondary Forest and Tea Plantations in Taiwan

台灣低海拔次生林和茶園之土壤二氧化碳通量比較

章國威(Kuo-Wei Chang) ； 高文媛(Wen-Yuan Kao)

《台灣林業科學》 24卷1期 (2009/03) Pp. 17-26

https://doi.org/10.7075/TJFS.200903.0017

摘要

本文測量台灣宜蘭地區次生林（冠層較密和較開闊區）和茶園（正在耕作和停耕區）在2004年六月到2005年七月間之土壤二氧化碳通量、土壤溫度和土壤含水量的變化。目的在量化和比較這兩種生態系其土壤二氧化碳通量以及檢視二氧化碳通量和環境因子（土壤溫度和土壤含水量）間的關係。測量發現土壤二氧化碳通量和土壤溫度有季節性變化；次生林土壤二氧化碳通量變化從1到3.5 μmol CO2m^(-2)s^(-1)，茶園則為0.5到5.0 μmol CO2 m^(-2)s^(-1)，此變化和土壤溫度變化有正相關，因此可經由此關係計算溫度每升高10度二氧化碳通量的增加倍率（以Q10值表示）；結果發現正在耕作的茶園區其Q10值最高(2.92)，而冠層較密的次生林區其Q10值最低(1.83)，停耕的茶園區和較開闊的次生林區其Q10值介於中間（分別為1.94和1.98），顯示正在耕作的茶園區其土壤二氧化碳通量變化對溫度變化最敏感。

關鍵字

土壤二氧化碳通量 ； 土壤溫度 ； 次生林 ； 茶園 ； Q10值

並列摘要

Soil CO2 efflux, soil temperatures, and soil water content of 2 stands in a secondary forest, with differing canopy openness, and 2 tea plantations, one actively cropped and the other abandoned for 2 yr, in Taiwan were measured monthly from June 2004 to July 2005. The first objective of this study was to quantify and compare soil CO2 efflux of the 4 stands. The second objective was to examine the relationship of environmental conditions, specially soil temperature and soil water contents, with soil CO2 efflux of the forest and tea plantations. Seasonal patterns were found in soil CO2 efflux and soil temperature but not in soil water content. The magnitude of the soil CO2 efflux varied from 1 to 3.5 μmol m^(-2)s^(-1) and from 0.5 to 5.0 μmol m^(-2)s^(-1) in the secondary forest and tea plantations, respectively. Within stands, seasonal changes in soil respiration were most highly correlated with soil temperature. The highest Q10 value, the factor by which the respiration rate differs for a temperature interval of 10℃, of 2.92 occurred in the actively cropped tea stand, the lowest of 1.83 was calculated for the open forest stand, and intermediate values of 1.94 and 1.98 were found in the dense forest stand and abandoned tea stand, respectively. The results indicate that among the 4 stands, the soil CO2 efflux of the actively cropped tea stand was most sensitive to changes in soil temperature.

並列關鍵字

soil CO2 efflux ； soil temperature ； secondary forest ； tea plantation ； Q10