[Objective] The effect of the addition of different proportion of exogenous organic matter on the forest soil organic carbon mineralization was discussed in this study in order to further understand the ecological relationship between the added exogenous organic matter and soil organic carbon.[Method] The dead leaves of Korean pine (Pinus koraiensis) and other broad-leaved species (e.g.Linden and maple) were collected in Korean pine broadleaved mixed forest experimental plots in Liangshui National Nature Reserve and regarded as exogenous organic matter.The mineralization process was imitated in the incubators through laboratory incubation method by adding different proportions of Korean pine dead leaves and broad dead leaves at different incubation temperature (25 ℃,30 ℃,and 35 ℃) and incubation days (5 d,10 d,20 d,35 d,60 d,and 90 d).The soil CO2 released under different treatments was measured by alkali absorption method,and the mineralization rate and cumulative mineralization amount of soil organic carbon were calculated.And then the priming effect of exogenous organic matters and temperature on soil organic carbon was analyzed.[Result] At the incubation temperatures of 25 ℃ and 35 ℃,the priming effect of dead broad leaves was better than that of dead Korean pine leaves;while at 30 ℃,the result was opposite.Under the three levels of incubation temperature,the addition of dead leaves produced a significant promoting effect on soil mineralization processes (P ＜ 0.05).At the temperature of 30 ℃,the addition of the exogenous organic matter resulted in the strongest priming effect on the soil organic carbon.[Conclusion] The priming effect of soil organic carbon in Korean pine broad-leaved mixed forest was influenced by multi-factors,such as the types of added exogenous organic matter,incubation temperature and days.%[目的]探讨添加不同比例外源有机物与温度对森林土壤有机碳矿化的影响,以期进一步认识二者与土壤有机碳的生态联系.[方法]将凉水国家级自然保护区红松阔叶混交林试验样地内收集的红松枯叶、椴树和枫桦枯叶(阔叶枯叶)作为外源有机物,通过实验室培养法,在恒温箱内模拟了红松枯叶和不同添加比例的阔叶枯叶在不同培养温度(25、30、35 ℃)和培养时间(5、10、20、35、60、90 d)的矿化过程,利用碱液吸收法测定了不同处理土壤CO2的释放量,计算了其有机碳矿化速率和累积矿化量,分析了其对土壤有机碳的激发效应.[结果]培养温度为25、35℃时,混合添加阔叶枯叶的激发效应优于红松枯叶的激发效应.培养温度为30℃时,添加红松枯叶的激发效应优于阔叶枯叶的激发效应.3个培养温度下,添加枯叶对土壤矿化过程具有显著的促进作用(P＜0.05).培养温度为30 ℃时,添加外源有机物对土壤有机碳的激发效应最优.[结论]红松阔叶混交林土壤有机碳的激发效应受添加外源有机物的种类、培养温度以及培养时间等许多因素的影响.
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