Microbial and enzyme activities in rhizosphere soil of different forest stand in karst and non karst areas

ObjectiveThis paper aims to clarify the effects of different forests on soil microorganism and soil enzyme activity under different geological conditions, providing a theoretical basis for further research on restoration of natural ecological system.

MethodThe soil samples were collected separately in rhizosphere of Eucalyptus robusta plantation, Pinus yunnanensis plantation and natural secondary forest growing up in karst and non-karst areas of Jianshui, Yunnan of southwestern China. The correlations between microorganisms and soil enzymes from different geological backgrounds and forests were studied by dilution coating and soil enzyme measurement.

ResultThe results showed that there was a significant difference between the number of actinomycetes in the rhizosphere soil of E. robusta and P. yunnanensis forests under the same geological background. The microbial quantity of secondary forest in karst area was 18.2×10⁵ cfu/g. Generally, influenced by the restoration patterns and geological conditions, the activities of soil enzymes were different. Correlation analysis showed that urease and catalase activity were positively correlated with the number of actinomycetes. There were interrelations between urease, acid phosphatase, carbonic anhydrase and catalase.

ConclusionThe results reveal that geological backgrounds, forest stand and the restoration patterns will affect soil microbial community composition and transformation of soil substance.