中文摘要：

以贵州西南部典型喀斯特地区花椒林下的石缝、石沟、石洞、石槽、石坑及一般土壤为研究对象,对0-20cm土层土壤团聚体有机碳和活性有机碳分布特征进行分析。结果表明,与一般土壤相比,石沟和石坑明显增加了原状土壤和各粒径团聚体土壤有机碳及活性有机碳的含量,而石槽和石洞则有所降低。除石沟外,有机碳含量较高的土壤主要增加了〉5mm粒级团聚体含量。随着土壤团聚体粒径的降低,有机碳和活性有机碳呈＂∨＂形分布,并在〈0.25mm粒级达到最大。团聚体对土壤有机碳和活性有机碳的贡献出现2个峰值,分别在5～2mm和1～0.5mm 2个粒级中出现,而〈0.25mm团聚体对有机碳和活性有机碳的贡献率最低。相关性分析表明,土壤团聚体活性有机碳含量与土壤团聚体总有机碳含量呈极显著正相关关系（r=0.796）,团聚体活性有机碳可以作为衡量喀斯特山区土壤团聚体有机碳动态的一个敏感性指标。

英文摘要：

Taking stone crevice,stone gully,stone cavern,stone groove,stone pit,and normal soil under Chinese prickly ash orchard in typical Karst mountain areas of southwest Guizhou province as research objects,analyzed the contents of soil organic carbon（SOC） and labile organic carbon（LOC） in soil aggregates from 0 to 20 cm.The results showed that：Compared with normal soil,stone gully and stone pit increased the contents of SOC and LOC in original soil and in each size fraction,while stone groove and stone cavern decreased.Except stone gully,higher content of SOC mainly increased the content of aggregate with 5 mm fraction.Distribution of SOC and LOC presented ＂V＂ curve with the fraction of aggregates decreasing,and the highest values were in 0.25 mm fraction.Aggregates contributed to SOC and LOC formed two peaks,one in 5～2 mm fraction and the other in 1～0.5 mm fraction,while the lowest in 0.25 mm fraction.The linearly positive correlation was found between content of LOC and total organic carbon in soil aggregates.The correlation coefficient which was extremely significant（r=0.796）.This showed that content of LOC in soil aggregates could be a sensitive index to indicate the dynamic of SOC in Karst mountain areas.