黄土高原草地植物叶脉性状沿环境梯度的变化规律  

Variation in leaf vein traits along environmental gradient in Loess Plateau grasslands

作　　者：张明[1] 高慧蓉 莫惟轶 陈爽[1] 朱荣 王小春 王志波 李丹洋 王瑞丽 ZHANG Ming;GAO Huirong;MO Weiyi;CHEN Shuang;ZHU Rong;WANG Xiaochun;WANG Zhibo;LI Danyang;WANG Ruili(College of Forestry,Northwest A&F University,Yangling 712100,China;Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,China;Qinling National Forest Ecosystem Research Station,Yangling 712100,China)

机构地区：[1]西北农林科技大学,杨凌712100 [2]西北农林科技大学水土保持研究所,杨凌712100 [3]中国科学院水利部水土保持研究所,杨凌712100 [4]陕西秦岭森林生态系统国家野外科学观测研究站,杨凌712100

出　　处：《生态学报》2022年第19期8082-8093,共12页Acta Ecologica Sinica

基　　金：国家重点研发计划项目(2017YFA0604803);陕西省高校科协青年人才托举计划项目(20200203);陕西省自然科学基础研究计划一般项目(2019JQ-028);陕西省博士后科研资助项目(2018BSHEDZZ141)。

摘　　要：叶脉在维持叶片水分和光合能力方面具有重要作用,研究植物叶脉沿环境梯度的变化规律有利于从生理结构的角度探究植物叶片对环境变化的适应策略。以黄土高原中部为研究区域,沿水分和养分梯度从东向西选取10个取样点,涵盖了3种主要的植被带类型(森林草原、典型草原和荒漠草原),共获得519种植物叶片并测定其叶脉性状,包括叶脉密度(VLA,mm/mm^(2))、叶脉直径(VD,μm)和单位面积叶脉体积(VV,μm^(3)/mm^(2)),旨在探究不同脉型植物(包括网状脉、平行脉和单叶脉)叶脉性状的变异规律。结果表明:(1)黄土高原植物VD和VV沿经度增加减小,而VLA无明显变化(P>0.05)。(2)在不同脉型植物中VLA和VD的负相关关系只在网状脉和平行脉中存在,VLA和VV的正相关关系只在网状脉存在,VD和VV的正相关关系在不同脉型植物中均存在。(3)黄土高原自东向西随经度减小,网状脉植物的3种叶脉性状均显著增大(P<0.01),但变化趋势较弱(R~2=0.02—0.07);平行脉VLA无显著变化,VD和VV显著减小(P<0.01);然而,单叶脉植物的3种叶脉性状均无显著变化(P>0.05)。(4)叶脉类型是影响叶脉性状变异的主要因素(解释度为27.84%—62.25%)。环境因子中,土壤因子(主要是土壤水分和养分含量)对3种叶脉性状的解释度(0.54%—2.91%)大于气候因子(0.02%—0.77%)。这些结果表明,不同脉型植物具有不同的适应策略,未来在研究叶脉对环境变化的响应和变异规律时要考虑到叶脉类型的影响。Leaf vein plays an important role in maintaining leaf water state and photosynthetic capacity.Knowledge of the variation in leaf vein traits along the environmental gradient is helpful for us to explore the plants′adaptive strategies to environmental changes from the perspective of plant physiological structure.In this study,we selected 10 sampling sites from east to west along the water and nutrient gradients in the middle of the Loess Plateau,which covered the three vegetation types,including forest grassland,typical grassland and desert grassland.In total,the leaves of 519 plant species were sampled and their leaf vein traits were measured,including vein length per leaf area(VLA,mm/mm^(2)),vein diameter(VD,μm),and vein volume per leaf area(VV,μm^(3)/mm^(2)).We aimed to explore the relationships among three leaf vein traits of different leaf vein types(i.e.,reticulate vein,parallel vein and single vein)and their variation along environmental gradients.The results showed as follows:(1)In Loess Plateau,the VD and VV increased with the decrease of longitude,while VLA did not change significantly along the longitude(P>0.05).(2)In plants of different leaf vein types,the negative correlation between VLA and VD was only found in reticulate vein and parallel vein,the positive correlation between VLA and VV was only found in reticulate vein.However,the positive correlation between VD and VV was found in all leaf vein types.(3)As the longitude decreased from east to west,three leaf vein traits of reticulate vein plants significantly increased(P<0.01),but these variation trends were all weak(R~2=0.02—0.07).For parallel vein plants,VLA did not exhibit significantly trend along the longitude(P>0.05),while VD and VV decreased significantly as the longitude decreased(P<0.01).However,there were no significantly longitudinal patterns in the three leaf vein traits of single vein plants(P>0.05).(4)Vein type was the main factor driving the variation of leaf vein traits,with 27.84%—62.25%of the total variation explained.Amo

关 键 词：黄土高原 叶脉类型 叶脉性状 水分和养分梯度 

分 类 号：S812[农业科学—草业科学]