The Effects Of Nitrogen Deposition On Ecological Stoichiometry Of Leaf Of Moso Bamboo

Studying ecological stoichiometry is an approach to understand the response of plant to environmental change.As one of the important phenomenon of global change,increasing nitrogen(N)deposition would have an impact on the leaf’s ecological stoichiometry of plants.Moso bamboo forest is the highly representative type of plantation forests in subtropical China and the most important source of non-wood forest products in China.Now,more than 50% of Moso bamboo plantations has been intensively managed.These management practices will influence the ecological stoichiometry of Moso bamboo.Up to now,the effects of management level and N deposition on ecological stoichiometry,singly or combinedly,are still poorly understood.We conducted a field experiment to study the effects of simulated N deposition on ecological stoichiometry of leaves of Moso bamboo under extensive and intensive management.The results showed that:(1)Intensive management significantly increased C and P contents of leaves from both 1-year-old and 3-year-old bamboo,as well as N content from 3-year-old bamboo(P<0.05).Under both two management level,the C content of leaves from 1-year-old bamboo was higher than that from 3-year-old bamboo,but P content showed reverse trend.Management level significantly affected the contents of C,N,P contents and C:N,C:P,N:P ratios of leaves,.Our findings indicate that the productivity of Moso bamboo with the two management patterns were limited by N element.(2)Simulated N deposition significantly increased contents of C,N and P of leaves of Moso bamboo under extensive management(P<0.05),and these effects on C and P contents became stronger generally with N deposition level.The contents of C,N and P of leaves did not show regular changes between Moso bamboo of different age under the same N deposition level.The N deposition level alone and combined with Moso bamboo age had significant effects on the contents of C,N and P and ratios of C: N,C: P and N: P,while Moso bamboo age alone only significantly impacted C content and C: N ratio.Our findings indicate that the productivity of Moso bamboo forest under extensive management still was limited by N element.(3)C,N,P contents of leaves from both 1-year-old and 3-year-old Moso bamboo under intensive management generally showed increasing trend with N deposition.The contents of C,N and P of leaves did not show regular changes between Moso bamboo of different age under the same N deposition level.Nitrogen deposition level and its interaction with age of bamboo leaf of C,N,P content and C: N,C,P,N: P have a significant impact,bamboo age of bamboo leaf N content have a significant impact,for C,P content and C:N,C,P,N:P has a significant impact.Our findings indicate that the productivity of Moso bamboo forest under intensive management still was limited by N element.