[Objective]The aim of this study was to explore variation characteristics of soil microbial community diversity in purple soils at different re-vegetation stages on sloping-land in Hengyang,Hunan Province,South-central China.[Method]By using the spatial series to replace time series,four typical vegetation types,bare land,herbaceous and shrubby communities,as well as arboreal community,were selected to study the soil microbial community diversity by using the Biolog-ECO micro-plate technique. The four communities in purple soils on sloping-land were similar,and typical,and denoted four different re-vegetation stages.[Result]The soil microbial metabolic activity increased after re-vegetation(P < 0.05) significantly; The average well color development(AWCD),which is used to represent soil microbial activity and functional diversity,followed the order of arboreal community > shrubby community > herbaceous community >bare land at the different re-vegetation stages,and followed the order of 0 ~10 cm soil layer>10 ~25 cm soil layer>25 ~40 cm soil layer in the different soil layers at the same re-vegetation stage; The Shannon-Wiener species richness index( H) ,Shannon-Wiener evenness Index( E) ,Simpson dominance index( D) and McIntosh index( U) at four different re-vegetation stages were the highest in arboreal community(P<0. 05),the second in herbaceous community and shrubby community( P >0. 05 ) ,and the lowest in bare land ( P <0. 05 ); The carbon and nitrogen source utilization intensities followed the order of arboreal community>shrubby community>herbaceous community>bare land at different re-vegetation stages(P<0. 05),and followed the order of 0 -10 cm soil layer>10 -25 cm soil layer>25 -40 cm soil layer in different soil layers(P<0. 05); Principal component analysis(PCA) showed that two factors in relation to carbon and nitrogen sources from 31 carbon and nitrogen types could explain 37. 24% and 15. 89% of the variation,and carbohydrates,amino acids,intermediate metabolites,and secondary metabolites were the main carbon and nitrogen sources separating the two principal component factors; The results of correlation analysis indicated that total organic carbon( TOC) ,total nitrogen( TN) ,total phosphorus( TP) and available phosphorus( AP) had important influence on soil microbial community diversity. [Conclusion]All the results indicated that re-vegetation could enhance the soil microbial metabolic function which was beneficial to the reproduction of soil micro-organisms,thereby promoting an increase in soil carbon and nitrogen source utilization intensities.%【目的】探讨衡阳紫色土丘陵坡地不同植被恢复阶段土壤微生物群落多样性的变化特征，明确土壤微生物群落多样性对植被恢复的响应规律，探明研究区域退化生态系统恢复机制，为构建该区域生态系统恢复技术体系提供理论依据。【方法】采用空间序列代替时间序列方法，在研究区域内选择立地基本相似的裸荒地、草本群落、灌木群落与乔木群落4种典型的植被类型表示恢复的4个阶段，运用 Biolog-ECO 微平板技术，对4个阶段的土壤微生物群落多样性进行研究。【结果】植被恢复后土壤微生物群落代谢活性显著升高(P＜0.05)；相同土层不同恢复阶段代表土壤微生物活性和功能多样性的平均颜色变化率率大小顺序为乔木群落＞灌木群落＞草本群落＞祼荒地，相同恢复阶段不同土层的平均颜色变化率大小顺序为0～10 cm土层＞10～25 cm 土层＞25～40 cm 土层；4个恢复阶段土壤微生物群落的 Shannon-Wiener物种丰富度指数、Shannon-Wiener 均匀度指数、Simpson 优势度指数和 McIntosh指数以乔木群落最高(P＜0.05)，草本群落和灌木群落其次(P ＞0.05)，草本群落最低(P ＜0.05)；各恢复阶段对不同 C，N源利用强度的大小顺序为乔木群落＞灌木群落＞草本群落＞裸荒地(P ＜0.05)，不同土层对各 C，N源利用强度的大小顺序为0～10 cm 土层＞10～25 cm 土层＞25～40 cm 土层( P ＜0.05)；主成分分析表明，从31种 C，N 源类型提取的与 C，N 源利用相关的主成分1和主成分2分别能解释变量方差的37.24%和15.89%，在主成分分离中起主要贡献作用的 C，N源为糖类、氨基酸类以及代谢中间产物和次生代谢物；相关分析表明，土壤含水量、土壤总有机碳、全氮、全磷和速效磷对土壤微生物群落多样性具有重要影响。【结论】植被恢复可使土壤微生物代谢功能增强，土壤微生物繁殖快、数量大，从而促进土壤微生物对土壤 C，N源的利用强度。
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