Effects of mulching management on soil and foliar C, N and P stoichiometry in bamboo (Phyllostachys violascens) plantations

Mulching with rice straw and chaff in bamboo (Phyllostachys violascens) plantations for early shooting and high profit resulted in stand degradation in Zhejiang, China. The present study explored the possible mechanisms of degradation by analysing the effects of intensive mulching on soil and foliar carbon (C), nitrogen (N), phosphorous (P) stoichiometry in bamboo plantations. Results showed that mulching for 3 and 6 years increased soil C, N, P and the ratios of C:P and N:P but decreased soil pH. Mulching decreased foliar C, N and P but increased the C:N, C:P and N:P ratios. Foliar N:P ratio had positive correlation with soil P and pH and negative correlation with soil N:P and C:P ratios. It appeared that changes in soil C, N and P stoichiometry caused by long-term mulching management resulted in enhanced function of P as the limiting factor and soil acidification. Therefore, bamboo stand degradation caused by mulching management may cause imbalance in the relationship between C, N and P, inhibit absorption of N and P by roots as well as decrease foliar C assimilation capacity