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Biological cycling of mainnutrients is one of the basic functional processes of forest ecosystem and its characteristic is a determinant factor for sustainable forest objectives.Researches on the characteristics of biological cycling of Phyllostachys edulis forests are necessary in bamboo growing regions,such as southeastern China,that have not been studied form this perspective.Especially,to explore the impact of long-term fertilization on the characteristics of biocycle in P.edulis forests can provide a scientific basis to maintain the long-term productivity in P.edulis forest.The study investigated the distribution of nitrogen(N),phosphorous(P),potassium(K),calcium(Ca)and magnesium(Mg)elements and biocycle characteristics in southeastern Chinas Tianbaoyan Nature Reserve using P.edulis forests without fertilizer as control(Ⅰ),with five years of fertilization(Ⅱ)and with 13 years of fertilization(Ⅲ).The results showed that the order of five elements at different levels of three types was soil layer >tree layer>litterfall layer>shrub layer>herb layer.The nutrient accumulation level at soil layer accounted for over 99%of total nutrient accumulation,and the nutrient accumulation amount had an important role in maintaining the long-term productivity of P.edulis forest.The order of nutrient accumulation at soil layer,tree layer and litterfall layer of three types of P.edulis forests was Ⅲ> Ⅱ >Ⅰ.The order of nutrient accumulation of shrub layer and herb layer was Ⅰ > Ⅱ > Ⅲ.Fertilization can increase the nutrient element accumulation in soil layer,tree layer and litterfall layer of P.edulis forests,and reduce it in shrub layer and herb layer.The order of nutrient utilization factor in three types of forests was Ⅰ>Ⅲ>Ⅱ,the order of circulating factor was Ⅲ> Ⅱ> Ⅰ,and the order of turnaround time was Ⅱ > Ⅰ > Ⅲ.Fertilization can reduce the nutrient utilization factor,increase the nutrient circulating factor,decrease the nutrient turnaround time,and benefit the maintenance of forest nutrient balance.In P.edulis forests,fertilization is an important approach to supplement soil nutrients and maintain nutrient balance,but it reduced the nutrient accumulation at shrub layer and herb layer,which may adversely affect the long-term productivity of P.edulis forests.It may be an effective way to maintain the productivity of P.edulis forests to combine,rotate fertilization and other conventional means or to interval applying same method.