Seasonal Dynamics of Leaf Stoichiometry of Phragmites australis : A Case Study From Yangguan Wetland, Dunhuang, China

Leaf stoichiometry can enhance our understanding of leaf elements' (C, N and P) concentrations and their corresponding ratios in an ecosystem with seasonal environment changes. This study quantified the seasonal dynamics of leaf stoichiometry of from Yangguan wetland, Dunhuang, China as a case study example. The leaf C concentration (LC) of changed between seasons and was 392.26 (g×kg ), 417.35 (g×kg ) and 392.58 (g×kg ) in spring, summer and autumn, respectively. Leaf N and P concentrations (LN and LP) were 23.49 (g×kg ), and 17.54 (g×kg ) and 5.86 (g×kg ), and 1.00 (g×kg ), 0.75 (g×kg ) and 0.16 (g×kg ), respectively, in the three seasons. The maximum (77.68) and the minimum values (17.00) of LC:LN were observed in the autumn and spring, respectively. Seasonal variations in LC:LP also showed a similar trend, with the greatest value of 3015.91 in autumn and the lowest value of 429.39 in spring. However, the highest (45.67) and the lowest values (24.18) of LN:LP were observed in autumn and summer, respectively, indicating that the growth of was mainly affected by P. Based on these results, it can be concluded that adopted a competition strategy during the early growth stage but took on a defense life strategy at the late growth stage to cope with various environments.