Studies on soil microorganisms and enzyme activities of cypress funebris forest in different transforming patterns

Objective In order to provide a theoretical foundation and a technical reference for transformation of the low-efficiency forest, the effects of different transformation patterns on the transformation of cypress (Cupressus funebris) funebris forest were investigated.

Method The spatiotemporal distribution patterns of soil microorganisms and enzyme activities in five cropping patternswalnut(Juglans regia, no grass), walnut+chicory(Cichorium intybus), walnut+alfalfa(Medicago sativa), walnut+ orchardgrass (Dactylis glomerata), pure cypress in the reform area of cypress funebris forest in Jingyang District, Deyang City were studied.

Result The quantities of soil microorganisms and enzyme activities both significantly increased after the transformation of the cypress funebris forest. Among the five patterns, the "walnut+chicory" pattern had the most significant effects with the number of soil microorganisms and the contents of catalase, sucrase, urease and alkalinep hosphatase increased by 112.5%, 7.7%, 33.0%, 39.1% and 62.9% respectively, and the values of all these factors were significantly higher in the upper layer(0-15 cm)than those in the lower layer(15-30 cm)(P < 0.05).There were different seasonal dynamics for three major microorganisms and the activities of four soil enzymes. The quantities of fungi, actinomycetes and bacteria was the highest in summer, spring and autumn respectively, and the catalase activity was the highest in autumn, while the other three enzyme activities were the highest in spring. The total number of soil microorganism was positively correlated with the activities of sucrase and alkaline (P < 0.05), and strongly positively correlated with the catalase activity(P < 0.01).

Conclusion All transformation patterns improved soil fertilities in varying degrees, with the most effective pattern being "walnut+chicory".