Effects of vegetation restoration in purplish soil hilly land on soil microbial characteristics and enzyme activities

摘要

Spatial sequence, instead of time sequence, is used to analyse the effect of vegetation restoration in purplish soil hilly land of Hengyang of Hunan Province on soil microbial characteristics and enzyme activities and analyse their relationship. Results show (1) with the progress of vegetation restoration, soil dissolved carbon, alkali-hydrolysable nitrogen and rapidly available phosphorus, microorganism quantity, carbon-nitrogen content, respiration rate and activities of urease, invertase and catalase are significantly increased (p 0.05). (2) Compared with the early stage (I), soil respiration rates in the middle and early stage (II), the middle and late stage (III) and the late stage (IV) increase significantly, particularly in the middle and early stage (II) (p 0.05). Moreover, compared with the initial stage (I), the differences in soil microbial biomass carbon and nitrogen ratio and metabolic entropy in the middle and early stage (II), the middle and late stage (III) and the late stage (IV) are not significant (p 0.05). (3) Correlation analysis shows that soluble carbon, alkali-hydrolysable nitrogen and rapidly available phosphorus are pairwise correlated. These soil indicators have good correlation with microbial biomass carbon and nitrogen content as well as urease, invertase and catalase activities (p 0.001). Findings show that vegetation restoration can significantly improve soil biological properties.