Quantitative characteristics of soil aggregate-associated enzymes in pure Eucalyptus forest and mixed eucalyptus forest

The activities and stoichiometric ratios of carbon, nitrogen and phosphorus acquisition enzymes(β-glucosidase, β-N-acetylaminoglucosidase, leucine aminopeptidase, acidic phosphatase) activities and stoichiometric ratios. The results showed that the activities of soil-acquired enzymes were higher in eucalyptus mixed forests than in eucalyptus pure forests, and all three forests had the highest enzyme activities in agglomerates < 0.25 mm in size, while the enzyme activities were lower in large-size agglomerates( > 2 mm), and that there were correlations between the enzyme activities and stoichiometric characteristics of agglomerates and the pH, organic carbon and total nitrogen of the soils. The results of zymometric characterization reflected that soil microorganisms in the three types of Eucalyptus plantations were more severely restricted by C and P than by N. Among the three forests, soil microorganisms in the mixed forests were more restricted. Mixed eucalyptus and broad forests can improve the soil structure, increase the organic matter content and microbial activity, and increase the efficiency of nutrient transportation, which is conducive to the enhancement of soil enzyme activity, but at the same time, it will aggravate the microbial limitation by C and P.