黄耆属草本植物根部导管结构对环境因子的响应  

Effects of environmental factors on root vessel anatomical traits of Astragalus herbs

作　　者：董彦君 李宗善 陈颖[4] 高光耀 王聪 王晓春[4] DONG Yanjun;LI Zongshan;CHEN Ying;GAO Guangyao;WANG Cong;WANG Xiaochun(State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;University of Chinese Academy of Sciences,Beijing 100049,China;National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi,Xi’an 710061,China;Center for Ecolog-ical Research,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]中国科学院生态环境研究中心城市与区域生态国家重点实验室,北京100085 [2]中国科学院大学,北京100049 [3]陕西黄土高原地球关键带国家野外科学观测研究站,西安710061 [4]东北林业大学生态研究中心,哈尔滨150040

出　　处：《生态学杂志》2023年第12期2936-2943,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41991233,42071125,41877539)资助。

摘　　要：干旱半干旱区植物的导水解剖结构对环境条件的适应性具有重要生态学意义。本研究采用石蜡切片法获取了中国干旱半干旱区4种黄耆属草本植物——斜茎黄耆(Astragalus adsurgens)、黄耆(Astragalus membranaceus)、乳白黄耆(Astragalus galactites)和草木樨状黄耆(Astragalus melilotoides)根部导管解剖结构的特征,分析了导管解剖性状对环境因子(温度和降水)的响应特征。结果发现,黄耆属草本物种的导管解剖性状(导管数量、导管分数、平均导管面积、平均水力传导率和水力直径)具有较大的变异特征。随着降水和温度的增加,导管数量显著下降,而导水效率相关的性状(水力直径、平均导管面积和平均水力传导率)则具有上升趋势。这表明在降水量和温度较低地区,较多的导管数量和较小的导管面积导致黄耆属草本采取导水安全优先策略;在降水量和温度较高的地区,较少的导管数量和较大的导管面积导致黄耆属草本采取导水效率优先策略。黄耆属草本根的解剖性状与温度的相关性均高于其与降水的相关性,表明温度可能是影响其导管解剖结构的主要气候因子。Hydraulic anatomical structure plays an important role in the adaptation of plants in arid and semiarid areas.In this study,we used paraffin section method to obtain the anatomical traits of root vessels of four Astragalus herb species(Astragalus adsurgens,Astragalus membranaceus,Astragalus galactites,and Astragalus melilotoides) in arid and semiarid regions of China.Pearson correlation was used to analyze the responses of vessel anatomical features to environmental factors(temperature and precipitation).The results showed that there was great variability in the vessel anatomical traits(vessel number,vessel fraction,mean vessel area,mean hydraulic conductivity,and hydraulic diameter) of Astragalus herbs.With the increases of precipitation and temperature,the vessel number of Astragalus herbs significantly decreased,while the traits related to hydraulic conductivity(hydraulic diameter,mean vessel area and mean hydraulic conductivity) significantly increased,which suggested that Astragalus herbs from areas with low precipitation and temperature have higher hydraulic safety(more and smaller vessel),while those from areas with high precipitation and temperature have higher hydraulic efficiency(fewer and larger vessel).The correlation coefficients between root anatomical traits and temperature were higher than those with precipitation,which suggested that temperature may be the main climatic factor limiting the anatomical structures of Astragalus herbs in arid and semiarid areas of China.

关 键 词：水力结构 导水策略 干旱半干旱区 黄耆属 

分 类 号：Q948.1[生物学—植物学]