中文摘要：

【目的】从草地生态系统土壤有机碳（SOil organic carbon，SOC）储量分布特征来确定合理的放牧管理方式并为区域SOC储量估算提供依据。【方法】采用野外调查法分层测定典型草原O-100cmSOC储量。【结果】①3个研究样地SOC储量为9．72-14．84kg·m^-1；②具有空间距离的3个研究样地土壤碳储量差异无统计学意义，样地内4种处理之间SOC储量差异显著，且均表现为中度放牧处理（moderate grazing，MG）〉轻度放牧处理（1ight grazing，LG）〉重度放牧处理（heavy grazing，HG）〉对照（control area，CK）；③随土层深度的增加SOC储量呈递减趋势，且不同土层之间SOC均有显著性差异。SOC储量与土层深度呈极显著相关关系（P〈0．01），这种关系可以用对数和线性方程描述。【结论】典型草原亚带草地生态系统SOC储量具有相对稳定性，且呈现明显的垂直递减特征；同一植被亚带不同处理对SOC储量的影响显著高于空间差异；适度放牧利用有利于草地生态系统SOC固持。

英文摘要：

[Objective] The distribution characteristics of soil organic carbon （SOC） storage were studied for the purpose to determine the reasonable grazing management way and provide a basis for the regional carbon estimation in grassland ecosystem. [Method] The SOC storage of 0-100 cm soil depth was measured by using field method of stratified sampling in the typical steppe. [Result] The SOC storage was between 9.72-14.84 kg.m^-2 in the three study plots. No significant difference was found in SOC storage in three study plots of spatial distance. The significant difference of SOC storage was found between four different grazing managements treatments in study area, and the order was moderate grazing （MG）〉light grazing （LG）〉heavy grazing （HG）〉control area （CK）. The SOC storage decreased with the increasing of soil depth, and a significant difference was detected between SOC among different soil layers. A positive significant relationship was found between SOC storage and soil layer （P〈0.01）, and the relationship could be described by using logarithmic and linear equations. [Conclusion] The SOC storage was relatively stable in the typical steppe, and presented a vertical descending characteristics. The effect of different grazing managements on SOC storage in the same vegetation type was significantly higher than the effect of spatial distance. Moderate grazing is benefit for carbon fmation of grassland ecosystem.