关键词: Biolog-ECO, 植被恢复, 土壤微生物群落, 多样性, 紫色土, 衡阳

Abstract: [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.

Key words: Biolog-ECO, re-vegetation, soil microbial community, diversity, purple soils, Hengyang