黄土区刺槐林不同深度土壤枯落物的腐解能力

摘要

The decomposition ability of different depth of litters was studied. The changes of SOC, POC and TO of soils adding litters of Robinia pseudoacacia forest in two four-month phases and CO2 accumulation value of soil samples in three depths were analyzed using field and laboratory incubational method. SOC, POC and TN showed an increase and decrease complementation trend in the two phases; and the variation range degree decreases with the depth increasing. For laboratory incubational experiment, the order of cumulative release amount of CO2 was 20 cm>60 cm>40 cm, which was caused by the differences of SOC components of experimental soils.%为了探索不同深度土壤对枯落物腐解的影响差异,通过对3个剌槐林样地C1、C2、C3的野外培育试验和室内培养试验,研究分析了添加枯落物后土壤有机碳(SOC)、颗粒态有机碳(POC)和总氮(TN)周期为4个月的两个阶段的含量变化以及3个深度土样59 d的CO2累计释放量.结果表明,SOC、POC及TN在两个阶段的变化量呈增减互补趋势,其变化幅度随深度增加而减小,表明枯落物腐解速率降低；室内培养试验中,SOC组分的差异造成了CO2累计释放量为20 cm＞60 cm＞40 cm.