Response of Leaf Functional Traits to Different Light Regimes in an Evergreen Broad-Leaved Forest in the Jinyun Mountain | 不同光环境下6种常绿阔叶林树种苗期的叶片功能性状

Chinese. 研究不同光环境（旷地、林窗、林下）下缙云山常绿阔叶林6种常见树种的叶片功能性状及性状间的相互关系,并对不同演替阶段物种的叶片性状进行比较。结果表明：1）在光照较弱的林窗和林下,树种的比叶面积（SLA）、叶片氮含量（LNC）和叶片N：P比显著高于光照充足的旷地,叶干物质含量（LDMC）变化趋势与SLA相反,叶片磷含量（LPC）在3种光环境下无显著差异;2）演替前期种具有较高的SLA,LNC和LPC,而演替后期种的LDMC和N：P比显著高于演替前期种。随光照的减弱,演替前期种的LPC无显著差异,而演替后期种则呈下降趋势;3）在3种光环境下,LNC与LPC,SLA正相关,LDMC与LPC,LNC,SLA负相关,N：P比与LPC负相关,而与LNC无显著相关性。随光照的减弱,SLA-LDMC,LPC-N：P及LNC-LPC性状关系沿共同斜率或Y轴截距发生了显著的变异,表明研究材料主要通过增大SLA,LNC及维持较高的N：P比来适应低光环境,不同演替阶段物种适应策略不同;叶功能性状间的权衡关系沿光资源梯度发生了相应的变化。

English. Leaf functional traits are closely associated with resource acquisition and utilization as well as changes of environment.In this study,we studied leaf functional traits of six common species in an evergreen broad-leaved forest in the Jinyun Mountain and their relationships under different light regimes and compared leaf traits of species at different successional stages.The results showed that：1） specific leaf area（SLA）,mass-based leaf nitrogen content（LNC） and N：P ratio in gaps and understory were significantly higher than those in open areas of forest edge.Leaf dry matter content（LDMC） in gaps was significantly lower than that in open areas of forest edge.There were no significant differences in mass-based leaf phosphorus content（LPC） among light regimes.2） Species at different successional stages had different leaf carbon investment strategies.Early-successional species trend to have higher SLA,LNC,and LPC but lower LDMC and N：P ratio than late-successional species.3） Across species,LNC was positively correlated with SLA and LPC,and LDMC was negatively correlated with LPC,LNC and SLA.N：P ratio was negatively correlated with LPC,but not correlated with LNC.The relationships between leaf traits under different light regimes were generally the same,but varied significantly along common slope（excepted LNC-LPC） and Y-intercept.These results indicated that the trade-offs of multi-traits had dynamic changes to adapt to different light regimes,and plants adapted to low-light environment by increasing SLA,LNC or maintaining a high N：P ratio.