Foliar C,N and P stoichiometry in subtropical evergreen broad-leaf forest in Shitai county,Anhui province

This study focused on the foliage of major plants in a subtropical evergreen broad-leaf forest in Shitai,Anhui province,and we tried to figure out the trait of foliar C,N and P at different types,and strived to reveal their relationships. The result showed that foliar C concentrations were ranged from 400. 08 to 519. 36 mg / g,N from 5. 15 to 15. 39 mg / g and P from 0. 30 to 0. 97 mg / g for 28 major species. The ratios of m( C) ∶ m( N),m( C) ∶ m( P) and m( N) ∶ m( P) was 29. 99- 92. 25,467. 01- 1 443. 81 and 10. 01- 29. 29,respectively. There was a strong correlation between N and P,m( C) ∶ m( N) and m( C) ∶ m( P). The change of m( N) ∶ m( P) ratio was mainly determined by the P concentration. As for the relationships among C,N,P concentrations in different types,we concluded that ratio of foliar m( C)∶ m( N) was 59. 68 in shrubs,51. 56 in trees,and 44. 50 in herb,and significant difference was found between the shrub and herb species. The ratio of foliar m( C) ∶ m( P) was 1 043. 4 in shrubs,818. 78 in herb,808. 35 in trees.There was significant difference between shrubs and both trees and herbs. These showed that maximum utilization efficiency of N and P existed in shrub species. The m( N) ∶ m( P) ratios for shrubs,herbs and trees were more than 16,indicating that evergreen broad-leaf forest was restricted by P utilization. The higher ratio of m( C) ∶ m( P) manifested that plants would be more efficient for the restriction elements,reflecting the responses of plants adapting to the environment.