摘要
[目的]探索刺槐幼苗在干旱胁迫下的适应策略,为植被恢复过程中人工刺槐林的造林选址提供科学依据。[方法]采用盆栽控水实验法,以1年生刺槐幼苗为实验对象,设置4个水分梯度(分别为田间持水量的75%~90%,60%~75%,45%~60%,30%~45%),研究水分胁迫下刺槐幼苗的适应机制。[结果]①中度(45%~60%)和重度水分胁迫(30%~45%)明显抑制幼苗生长,其株高、地径和冠幅显著低于对照组(75%~90%),轻度水分胁迫(60%~75%)与对照组差异不显著,在实验结束时其生长状态优于对照组;②随土壤水分胁迫程度加深,刺槐幼苗根磷含量升高,比叶面积和比根长减小,叶厚度和叶组织密度增大;③中度(45%~60%)和重度水分胁迫(30%~45%)显著减少了幼苗的生物量积累,提高了幼苗的根冠比。[结论]刺槐幼苗通过将同化物质相对多的投入到防御组织的策略来适应干旱环境。重度水分胁迫严重抑制幼苗的生长,而在轻度水分胁迫下,幼苗能取得最大生长收益。
[Objective]The adaptation strategies of Robinia pseudoacacia seedlings under drought stress were explored,in order to provide support for afforestation site selection of artificial Robinia pseudoacacia forests during vegetation restoration.[Methods]Using the potted water control experiment method,the annual seedlings were used as experimental subjects to study the adaptation mechanism of Robinia pseudoacacia seedlings.Four water gradients were respectively set as follows:75%~90%,60%~75%,45%~60%,and 30%~45%of soil water holding capacity.[Results]①Moderate water stress(45%~60%)and severe water stress(30%~45%)significantly inhibited the growth of seedling,and the plant height,ground diameter and crown width were significantly lower than those of the control group(75%~90%).②With the deepening of soil water stress,root phosphorus content,specific leaf area and specific root length decreased,while leaf thickness and leaf tissue density increased in Robinia pseudoacacia seedlings.There was no significant different between mild water stress(60%~75%)and the control group,and the growth state of mild water stress was even better than that of the control group at the end of the experiment.③Moderate water stress and severe water stress significantly reduced the biomass accumulation of seedlings and increased the root-shoot ratio of seedlings.[Conclusions]Robinia pseudoacacia seedlings adapts to the arid environment by investing a relatively large amount of assimilated material into the defense organization.Severe water stress inhibited the growth of seedlings seriously,while under mild water stress,seedlings could achieve maximum growth benefit.
作者
唐洋
温仲明
王杨
刘静
Tang Yang;Wen Zhongming;Wang Yang;Liu Jing(Institute of Soil and Water Conservation,NorthwestA&F University,Yangling,Shaanxi 712100,China;College of Grasland Agriculture,Northwest A&F University,Yangling,Shaanxi 712100,China;Research Center of Soil and Water Conservation and Ecological Environment,Chinese Academy of Sciences and Ministry of Education,Yangling,Shaanxi 712100,China)
出处
《水土保持通报》
CSCD
北大核心
2019年第6期98-105,共8页
Bulletin of Soil and Water Conservation
基金
国家自然科学基金项目“黄土高原刺槐环境适应机制、成本与群落性状结构及功能变化”(41671289)。
关键词
刺槐
水分胁迫
功能性状
生物量
适应机制
Robinia pseudoacacia
water stress
functional traits
biomass distribution
adaptation mechanism