亚热带毛竹人工林土壤呼吸组分动态变化及其影响因素

利用Li-8100土壤碳通量测量系统，研究了2013年4月—2014年3月浙江临安市毛竹人工林土壤呼吸、异养呼吸和自养呼吸速率的动态变化规律.结果表明：毛竹人工林土壤总呼吸速率、异养呼吸速率和自养呼吸速率均呈现出明显的季节变化特征，最高值出现在7月，最低值出现在1月，年平均值分别为2.93、1.92和1.01 μmol CO₂·m^-2·s^-1.毛竹林土壤总呼吸、异养呼吸和自养呼吸年累积CO₂排放量分别为37.25、24.61和12.64 t CO₂·hm^-2·a^-1.土壤呼吸各组分均与土壤5 cm温度呈显著指数相关，土壤总呼吸、异养呼吸和自养呼吸的温度敏感系数Q₁₀值分别为2.05、1.95和2.34.土壤总呼吸速率、异养呼吸速率与土壤水溶性有机碳(WSOC)含量均呈显著相关，而自养呼吸与WSOC无显著相关性；土壤呼吸各组分与土壤含水〖JP2〗量以及微生物生物量碳均无显著相关性.土壤温度是影响毛竹人工林土壤呼吸及其组分季节变化的主要驱动因子，土壤WSOC含量是影响土壤总呼吸和异养呼吸的重要环境因子.

Dynamic changes in soil respiration components and their regulating factors in the Moso bamboo plantation in subtropical China.

Dynamic changes (from April 2013 to March 2014) in soil respiration components were investigated by Li 8100 in the Moso bamboo plantation in Lin’an City, Zhejiang Province. Results showed that the average annual values for the soil total respiration rate, heterotrophic respiration rate, and autotrophic respiration rate in the Moso bamboo plantation were 2.93, 1.92 and 1.01 μmol CO₂·m^-2·s^-1, respectively. The soil respiration rate and its components exhibited strongly a seasonal dynamic pattern. The maximum appeared in July 2013, and the minimum appeared in January 2014. The annual cumulative CO₂ emissions through soil respiration, heterotrophic respiration, and autotrophic respiration were 37.25, 24.61 and 12.64 t CO₂·hm^-2·a^-1, respectively. The soil respiration and its components showed a close relation with soil temperature of 5 cm depth, and the corresponding Q_10 values at 5 cm depth were 2.05, 1.95 and 2.34, respectively. Both the soil respiration and heterotrophic respiration were correlated to soil water soluble organic C (WSOC) content, but no significant relationship between autotrophic respiration and WSOC was observed. There were no significant relationships between soil respiration components and soil moisture content or microbial biomass C. The seasonal changes in soil respiration components in the Moso bamboo plantation were predominantly controlled by the soil temperature, and the soil WSOC content was an important environmental factor controlling total soil respiration and soil heterotrophic respiration.