常绿阔叶林常见树种根茎叶功能性状的相关性

Correlations between leaf,stem and root functional traits of common tree species in an evergreen broad-leaved forest

以有关植物各构件功能性状之间关系的3个主要假说(功能相似假说、结构相似假说和整体协调假说)为依据,研究植物3个构件根、茎、叶对应功能性状之间的关系,是目前植物功能性状研究领域的研究热点。本文以江西大岗山栲树天然阔叶林中常见的16个树种为研究对象,选择了植物比叶面积、比根长、各构件组织密度以及各构件碳、氮、磷含量等共15个功能性状指标。并将其分为结构性状和化学性状2大类,利用多重t检验和皮尔森相关检验对根、茎、叶3个构件对应功能性状的差异性和相关性进行了分析。结果表明:在结构性状方面,比叶面积和比根长之间相关性不显著;各构件组织密度差异显著,大小依次为叶>茎>根,茎和根的组织密度相关性比叶和茎、叶和根更强。在化学性状方面,各构件碳含量大小并无显著差异,且相关性极显著;氮含量从高到低依次为叶>小枝>细根,且叶和细根的氮含量相关性显著;磷含量从高到低依次为小枝>叶>细根,且3个构件之间磷含量都为正相关。从各构件结构性状的关系来看,研究结果支持结构相似假说;从各构件氮含量的关系来看,研究结果支持功能相似假说;从各构件碳含量和磷含量的关系来看,研究结果支持整体协调假说。整体来看,植物各个构件的功能性状之间耦合协调,反映了植物适应环境的生态策略。

In this paper we try to explain the relationships between the functional traits of different plant organs based on three hypotheses, i. e. , the structural similarity hypothesis, functional similarity hypothesis and above and below-ground coordination hypothesis. We selected sixteen main tree species in the evergreen broad-leaved forest in Dagangshan, Jiangxi Province. Fifteen functional traits of these species were measured, including specific leaf area, specific root length, tissue density, carbon content etc. , which could be classified into structural trait and chemical trait categories. Multiple t test and Pearson correlation test were used to analyze the correlations between functional traits of root, stem and leaf. For structural traits, there was no significant correlations between specific leaf area and specific root length. Tissue density differed significantly among the three organs and the correlation between stem and root tissue density was stronger than that between other organs. For chemical traits, the carbon contents showed little difference among the three organs and their pairwise correlations were extremely strong. The nitrogen content was higher in leaf, medium in twig and lower in fine root, and the correlations between leaf and root nitrogen contents were significant. Besides, twig phosphorous content was the highest, and the phosphorus contents of the three organs were positively related. Our results on the relationships of structural traits support the structural similarity hypothesis while the relationships of the nitrogen content support the functional hypothesis is supported traits of leaf, stem and environment. similarity hypothesis. Meanwhile, the above and below-ground coordination by our results on carbon and phosphorous content. In conclusion, the functional root are coupled and may reflect the ecological strategies of plants to adapt to the