荒漠区植物光合器官解剖结构对水分利用效率的指示作用  

Indicative effect of the anatomical structure of plant photosynthetic organ on WUE in desert region

作　　者：张海娜[1,2] 苏培玺[2] 李善家[1,2] 周紫鹃[1,2] 解婷婷[1] 赵庆芳[3] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所临泽内陆河流域研究站,兰州730000 [2]中国科学院寒旱区陆面过程与气候变化重点实验室,兰州730000 [3]西北师范大学生命科学学院,兰州730070

出　　处：《生态学报》2013年第16期4909-4918,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(91025026;31070359)

摘　　要：植物生理功能的发挥以结构为基础,因此,植物光合器官(叶片或同化枝)解剖结构会对水分利用效率(WUE)有一定的指示作用。通过对黑河流域优势种灌木光合器官的解剖特征和表征WUE的稳定碳同位素比率(δ13C)进行分析,试图从解剖结构的角度为荒漠植物WUE寻求一个有效的指示指标。结果显示:(1)除花棒外,轴状光合器官植物的δ13C值均高于叶状。(2)不同荒漠植物光合器官及不同组织厚度变化范围较广,叶厚度(Tl)或轴直径(Da)、角质层厚度(Tc)、表皮厚度(Te)、栅栏组织厚度(Tp)、海绵组织厚度(Ts)、贮水组织厚度(Ta)的最大值分别约为最小值的6.9、5.8、11、4、3.5和3.5倍。荒漠区多数轴状光合器官植物的Da以及Te高于叶状。(3)所研究优势种灌木的δ13C值与Tl或Da之间存在极显著的正相关关系(r=0.719,P<0.01),与不同组织厚度(Tc、Te、Tp、Ts和Ta)之间相关性不显著。由此可知,从植物光合器官的解剖结构来看,荒漠区植物的WUE可以用Tl或Da来表征,叶片越厚,越有利于植物高效利用水分,且轴状光合器官植物的WUE高于叶状。Affected by the extreme arid environment caused by salinization,high temperature and intensive radiation,desert plants change their structural characteristics,such as fleshy leaf,assimilating shoots,lots of epidermal hairs,thick cuticle and so on,to improve their water use efficiency.Structure being basis of function,the anatomic structure of photosynthetic organ（including leaf and assimilating shoot） of desert plants can indicate their water use efficiency.It has been improved that stable carbon isotope（δ13C value）,an indicator of long-term water use efficiency（WUE） of desert plants and a comprehensive value reflecting the whole life history of plants,was widely applied to illustrate the response of δ13C values in plants to environment factors.Therefore,there must exist an important relevance between plant anatomical structure and δ13C value to some degree.However,most of studies on plant anatomical structure have been focused on its relationships with drought resistance,environmental plasticity and plant taxonomy for a long time,little was known about its response to WUE indicated by δ13C value.In this paper,the relationship between plant anatomical structure and δ13C value was analysed in the middle reaches of Heihe River basin,in order to find an effective indicator for WUE from the point of plant anatomical structure.The results showed that：（1）all the plants with axial photosynthetic organs had higher δ13C values that those with leafy organs but Hedysarum scoparium.（2） The variation range of thicknesses of the photosynthetic organs and different tissues among different desert plants was large.The maximum value of the leaf thickness（Tl） or axis diameter（Da） was 6.9 times higher than the minimum,and those of cuticle thickness（Tc）,epidermis thickness（Te）,palisade tissue thickness（Tp）,spongy tissue thickness（Ts） and aqueous tissue thickness（Ta） were 5.8,11,4,3.5 and 3.5 times higher than the corresponding minimum,respectively.Tl or Da and Te of most desert

关 键 词：荒漠植物 解剖结构 长期水分利用效率 稳定碳同位素比率 

分 类 号：Q945[生物学—植物学]