安徽石台亚热带常绿阔叶林植物叶中 C、N、P特征分析

以安徽石台亚热带常绿阔叶林植物叶片为研究对象,分析了植物叶中C、N、P含量以及它们之间的化学计量关系,讨论了不同类型植物叶片的化学计量特征。结果显示:所研究的28种植物物种间差异明显,叶片中C含量为400.08～519.36 mg/g,N 为5.15～15.39 mg/g,P为0.30～0.97 mg/g,m(C):m(N)范围为29.99～92.25、m(C):m(P)的范围为467.01～1 443.81、m(N):m(P)的范围为10.01～29.29,且N与P、m(C):m(N)值与m(C):m(P)值之间呈现显著的正相关关系,m(N):m(P)的变化主要由P含量决定。不同生活型植物m(C):m(N)值从大到小表现为灌木(59.68)>乔木(51.56)>草本和藤本植物(44.50),草本和藤本植物与灌木之间m(C):m(N)差异显著; 不同植物m(C):m(P)值从大到小表现为灌木(1 043.4)>草本和藤本植物(818.78)>乔木(808.35),灌木与乔木、草本和藤本植物都存在显著差异。该地区灌木m(C):m(N)值和m(C):m(P)值均最高,说明灌木对N、P的利用效率最高。3种类型植物m(N):m(P)值均大于16,说明该地区常绿阔叶林主要受P限制。虽然植物受P限制,但其m(C):m(P)值含量较高,说明植物对其生长受限的元素利用效率会更高,这反映了植物对环境适应的一种对策。

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.