艾比湖不同水盐环境荒漠植物种间关联格局下的叶片功能性状差异分析

Analysis on differences in leaf functional traits of desert plants under interspecific association pattern in different water-salt environments of Ebinur Lake

本研究对艾比湖不同水盐环境荒漠植物的种间关联特征进行了分析,并比较了关联种对间植物叶片功能性状(叶片C、N、P和S含量)的差异。结果表明:高水盐(盐胁迫)和低水盐(干旱胁迫)环境下,艾比湖荒漠植物种间总体关联性均呈现不显著负关联,种间关系相对松散。从关联种对来看,2种不同水盐环境均以正关联种对居多,其中,低水盐环境下正关联种对数明显高于高水盐环境,种间互利关系更占优势;高水盐和低水盐环境下,盐节木〔Halocnemum strobilaceum(Pall.)Bieb.〕与其他物种间多表现为负相关,相关系数为-0.48~1.00;高水盐环境下,显著正相关种对多见于生物量较低的物种间。正关联种对的叶片C、N和S含量差值总体表现为高水盐环境高于低水盐环境,而负关联种对叶片N、P和S含量差值在低水盐环境下更高。高水盐环境下正关联种对的性状(叶片P含量除外)差值总体高于负关联种对,但在低水盐环境下则相反。综合研究表明:干旱胁迫下种间竞争往往使种间功能性状趋异,而互利作用则使种间功能性状趋同;盐胁迫下性状相似种对的竞争更加激烈,互利种对的功能性状差异明显。

The interspecific association characteristics of desert plants in different water-salt environments of Ebinur Lake were analyzed in this study,and the differences in leaf functional traits(contents of C,N,P and S in leaf)of associated species pairs were compared.The results show that in high water-salt(salt stress)and low water-salt(drought stress)environments,the overall interspecific association of desert plants of Ebinur Lake shows a non-significant negative association,and the interspecific relationship is relatively loose.In terms of associated species pairs,positively associated species pairs are more in two different water-salt environments,in which,the number of positively associated species pairs in low water-salt environment is evidently higher than that in high water-salt environment,and its interspecific beneficial relationship is more advantaged;in high water-salt and low water-salt environments,Halocnemum strobilaceum(Pall.)Bieb.mostly shows negative correlations with the other species,and the correlation coefficients are-0.48-1.00;significantly positively correlated species pairs in high water-salt environment are more commonly found among species with relative low biomass.The difference values of contents of C,N and S in leaves of positively associated species pairs in high water-salt environment are higher than those in low water-salt environment,while the difference values of contents of N,P and S in leaves of negatively associated species pairs are higher in low water-salt environment.The difference values of functional traits(except for leaf P content)of positively associated species pairs are higher than those of negatively associated species pairs in high water-salt environment,but it is the opposite in low water-salt environment.In conclusion,the interspecific competition under drought stress tends to make interspecific functional traits different,while the beneficial effect makes the interspecific functional traits similar;the competitions between species pairs with similar traits are more intense under salt stress,and the differences in functional traits of beneficial species pairs are evident.