亚热带毛竹林生态系统碳通量与土壤呼吸研究

Study on the carbon flux and soil respiration of Phyllostachys edulis forest ecosystem in subtropic China

以浙江省安吉县毛竹林（Phyllostachys edulis）生态系统为研究对象，利用开路涡度相关系统和LI-Cor 8150自动观测系统，分析2014年毛竹林生态系统碳通量和土壤呼吸速率变化特征及其影响因子。结果表明，毛竹林土壤呼吸速率日变化为单峰曲线，最高值出现在14：00～16：00，最低值出现在06：00；净生态系统交换量（NEE）存在明显日变化特征，变化趋势为“双峰曲线”，峰值分别出现在10：00和12：00；而生态系统呼吸（RE）和土壤呼吸速率呈相同的年变化趋势，为“单峰型”，夏季高、冬季低，且均对温度变化较敏感。毛竹林土壤呼吸速率和生态系统呼吸量（RE）主要受高于20℃大气温度和5 cm土壤温度影响，与水分相关关系不显著。

Based on the eddy covariance system （EC） and LI-8150 automatic monitoring system, this study observed the variation characteristics and impact factors of carbon flux and soil respiration of Phyl o-stachys edulis forest ecosystem in 2014 in Anji country, Zhejiang Province. The results showed that soil res-piration （RS） appeared a single diurnal pattern with the peaks at 14：00-16：00 and the trough at 06：00. The daily variation of net ecosystem exchange （NEE） also showed an obvious bimodal shape with the peaks ap-peared in the 10：00 and 12：00, respectively. The seasonal variation of ecosystem respiration （RE） and RS showed the same unimodal pattern with the maximum in summer and the minimum in winter, and were al sensitive to changes in temperature. The yearly RE and RS strongly depended on the air temperature above 20℃and soil temperature at 5 cm depth, but both did not have significant correlation with the soil water.