摩天岭北坡常绿阔叶林带主要优势种叶片C、N、P特征分析

Analysis on the characteristics of leave C,N and P of main dominant species in evergreen broad-leaved forest belt of motianling northern slope

【目的】研究植物叶片的C、N、P元素含量特征,揭示植物的养分利用策略及对环境的适应方式.【方法】以摩天岭北坡常绿阔叶林带23种主要优势种的叶片为研究对象,分析木本植物叶片中C、N、P计量特征以及相关性.【结果】23种植物叶片C、N、P含量范围分别为383.68～628.29、10.87～41.91、0.83～3.23 mg/g,C/N、C/P、N/P范围为10.48～41.09、143.50～538.72、5.34～22.76,其中C的变异系数最小,为9.46%,C/N的变异系数最大,为37.15%.乔灌植物叶片元素含量特征表现为乔木的C/N>灌木,而其他几个指标均小于灌木.相关性分析表明,23种植物叶片中C、N、P计量参数间有7对呈显著或极显著相关,其中乔木植物有5对,灌木有6对,说明木本植物元素含量间相关性是普遍存在的.其中,N-C/N、P-C/P在两个尺度上相关性一致,都呈极显著负相关,表明这两组相关性是较为稳定的.【结论】研究区木本植物叶片C含量较低且最稳定,N、P含量较高,变异较大,但养分利用效率较低(C/N和C/P较低).乔灌植物叶片养分含量特征虽有所不同,但差异不明显.两个不同尺度的相关性分析表明,木本植物元素含量间相关性是普遍存在的,且N-C/N、P-C/P较为稳定的.

【Objective】 The study of the contents of C,N and P elements in plant leaves helps to reveal the strategy of plant nutrient utilization and the adaptation to the environment.【Method】 Based on the plant leaves of evergreen broad-leaved forest belt on the northern slope of Motianling,the contents of C,N and P and their stoichiometric characteristics were analyzed,and their correlations were compared at different scales.【Result】 The contents of C,N and P in leaves of 23 plants ranged from 383.68 to 628.29 mg/g,10.87 to 41.91 mg/g and 0.83 to 3.23 mg/g,respectively.The contents of C/N,C/P and N/P ranged from 10.48 to 41.09,143.50 to 538.72 and 5.34 to 22.76,among which C had the smallest coefficient of variation(9.46%) and C/N had the largest coefficient of variation(37.15%).The characteristics of element content in leaves of arbor and shrub plants showed that C/N of arbor was higher than that of shrub,while other indexes were lower than that of shrub.The correlation analysis showed that 7 pairs of C,N and P measurement parameters were significantly correlated(P<0.05) or extremely significant(P<0.01),while 5 pairs of arbors and 6 pairs of shrubs were correlated,which indicated that the correlation between elements content of woody plants was universal.Among them,the correlation of N-C/N and P-C/P on two scales is identical,showing a very significant negative correlation(P<0.01),which indicates that the correlation between the two groups is relatively stable.【Conclusion】 The leaf C content of woody plants is lower and the most stable.The content of N and P is higher and the variation is larger,but the nutrient use efficiency is lower(C/N and C/P are lower).Although the nutrient contents of leaves of trees were different,the differences were not obvious.The correlation analysis of two different scales showed that the correlation between element contents in woody plants was universal,and N-C/N,P-C/P were relatively stable.