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作 者 ：王建林,欧阳华,王忠红,常天军,李鹏,沈振西,钟志明

期 刊 ：生态学报 2009年 29卷 7期 页码：3501~3508

关键词：高寒草原生态系统；活性有机碳；分布特征；影响因素；

Keywords:alpine grassland ecosystem, labile organic carbon, distribution characteristics, influential factors,

摘 要 ：对贡嘎南山-拉轨岗日山南坡高寒草原生态系统表层（0~20cm）土壤活性有机碳分布特征研究表明：表层（0~20 cm）土壤活性有机碳平均为(2.4986±0.7864) g/kg，占表层土壤有机碳的(12.7926±21.00)%。在海拔4424~4804m范围内，随着海拔升高，表层（0~20cm）土壤活性有机碳含量表现出先减少后增加的分布特征，有机碳活度也表现出先减少后增加的分布特征。影响表层土壤活性有机碳含量最关键的环境因子是地上生物量、0~10cm地下生物量、30~40cm地下生物量、20~30cm土壤含水量、0~20cm土壤容重、20~40cm土壤容重和土壤全N量；影响表层土壤有机碳活度最关键的环境因子则是植被盖度、20~30cm地下生物量、0~10cm土壤含水量、10~20cm土壤含水量、20~30cm土壤含水量、土壤有机质、土壤速效K和土壤全N量。

Abstract:The distribution characteristics of the topsoil (0-20cm) labile organic carbon of alpine grassland ecosystem at the south slope of Gongga south mountain-Laguigangri mountain were studied. The results showed that, the average content of the topsoil (0-20cm) labile organic carbon was (2.4986±0.7864) g/kg, accounting for (12.7926±21.00)% of the topsoil organic carbon in alpine grassland ecosystem at the south slope of Gongga south mountain-Laguigangri mountain. With increasing altitude, the distribution characteristics of the topsoil (0-20cm) labile organic carbon and organic carbon lability were decrease→increase within the altitude range of 4424-4804m. The key environmental factors influencing the content of topsoil labile organic carbon were overground biomass, biomass of underground 0-10cm and 30-40cm, moisture of underground 20-30cm, soil bulk density of underground 0-20cm and 20-40cm, and soil total Nitrogen content. However, the key environmental factors for the topsoil (0-20cm) organic carbon lability were vegetation coverage, 20-30cm belowground biomass, 0-10cm,10-20cm and 20-30cm underground soil moisture, soil organic matter, soil labile Potassium and soil total Nitrogen content.

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