蛛网萼叶功能性状随植物生长发育进程的变化

Changes in the functional traits of Platycrater arguta Sieb.et Zucc.leaves with plant growth and development

蛛网萼(Platycrater arguta Sieb.et Zucc.)是一种分布区域十分狭窄的珍稀濒危植物。本文以江西省蛛网萼群落为研究对象,通过测定不同发育阶段蛛网萼的叶厚度(LT)、叶面积(LA)、叶含水量(LWC)、比叶面积(SLA)、叶组织密度(LTD)、单位干重的叶氮含量(LNC)、叶磷含量(LPC)和叶氮磷比(N/P)等功能性状指标,分析了功能性状和投资策略随生长发育过程的变化特征。结果显示,蛛网萼的各种叶功能性状随生长发育进程呈现不同的变化规律,其中LA、LTD、N/P显著增加,LWC、SLA及LPC显著减少,而LT和LNC无显著变化。主成分分析及PCA排序结果表明,蛛网萼叶功能性状症候群随着生长发育进程朝着LT、LA、LTD、LNC和N/P增加,而SLA、LWC和LPC减小的方向变化,植物的生长投资策略由快收益向慢收益转变。

Platycrater arguta Sieb.et Zucc.is a rare and endangered plant with a very narrow distribution area.In this paper,we investigated changes in the leaf functional traits and investment strategies of P.arguta communities distributed in Jiangxi Province,China,at different growth and development stages.We measured leaf thickness(LT),leaf area(LA),leaf water content(LWC),specific leaf area(SLA),leaf tissue density(LTD),leaf nitrogen(LNC)and leaf phosphorus content(LPC)per unit dry mass,and N/P ratio(N/P)in plants at different growth and development stages.Results showed that the leaf functional traits of P.arguta changed with growth and development in different patterns.LA,LTD,and N/P increased significantly with the growth and development process,while LWC,SLA,and LPC decreased significantly,and LT and LNC showed no significant changes.Principal component analysis(PCA)and PCA ranking indicated that the leaf functional trait syndrome of P.arguta plants changed toward increasing LT,LA,LTD,LNC and N/P,and decreasing SLA,LWC,and LPC with growth and development,suggesting that the growth investment strategy of the plants changed from fast-profit to slow-profit.