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Organic mulches are widely used to improve shoots production in moso bamboo(Phyllostachys edulis)forests.However,continuous mulching management may cause bamboo forest degradation and affect the sustainable management.The objective of this study was to clarify the degradation mechanism and to provide theoretical basis for recovery.A complete randomized block design with four treatments was conducted,including mulching for 1 year(M1),2 years(M2),3 years(M3)and no-mulching management(NM).Soil nutrient contents,enzyme activities and microbial biomass were determined.With the increase of mulching years,soil pH value gradually reduced,causing soil acidification,but the content of soil organic matter was inclined to descend.Soil total nitrogen(TN),total phosphorus(TP)and total potassium(TK)contents showed an increasing trend,and they were significantly higher in mulching stands than those in NM treatment(P<0.05).Contents of soil available nutrients(available N,available P,available K)increased and then decreased with the increase of mulching years,and peaked in M1 treatment.With the increase of mulching years,soil stoichiometry ratio(C/N,C/P and N/P)gradually increased.Soil invertase,urease and acid phosphatase activities presented earlier increase and later decrease trend,and reached the maximum within one year after mulching.Total microbial biomass and that of individual groups changed greatly after mulching.Soil microbial biomass increased first and then decreased,and it was the largest in M1 treatment.The fungi:bacteria ratio decreased first and then increased,while the aerobic:anaerobic ratio showed the opposite trend.According to the overall results,long-term mulching management leads to soil acidification,the imbalance of nutrients proportion,abnormal enzyme activity and change of soil microbial flora,and rotated mulching management(mulching 1 year and then recuperating 1 year)should be recommended in practice.In addition,mulching materials should be removed in time at shooting period,and the amount of residue should be reduced.