植物生态学报 ›› 2017, Vol. 41 ›› Issue (9): 1020-1032.DOI: 10.17521/cjpe.2016.0366

• 综述 • 上一篇    

植物水分调节对策: 等水与非等水行为

罗丹丹, 王传宽*(), 金鹰   

  1. 东北林业大学生态研究中心, 哈尔滨 150040
  • 收稿日期:2016-11-29 修回日期:2017-05-31 出版日期:2017-09-10 发布日期:2017-10-23
  • 通讯作者: 王传宽
  • 基金资助:
    国家“十三五”重点研发计划项目(2016YFD00201)和教育部长江学者和创新团队发展计划(IRT_15R09)

Plant water-regulation strategies: Isohydric versus anisohydric behavior

Dan-Dan LUO, Chuan-Kuan WANG*(), Ying JIN   

  1. Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
  • Received:2016-11-29 Revised:2017-05-31 Online:2017-09-10 Published:2017-10-23
  • Contact: Chuan-Kuan WANG

摘要:

水分是植物存活、生长和分布过程中的必需资源, 阐明植物对干旱的应对和调节机制, 是植物生理生态学和全球变化生态学的重要研究命题。植物对不同气候与土壤水分条件的长期适应会形成由一整套相关联的性状组成的水分调节策略, 其中等水和非等水调节行为是两种典型的水分调节对策。区分并阐明植物的水分调节对策及其机制, 不但在干旱地区植物育种、植被修复等实践中有广泛的应用前景, 而且可为构建更精确的植被动态模型和预测气候变化情景下植被分布提供科学基础。该文首先阐述了等水和非等水调节行为的定义及3种定量分类方法: (1)基于气孔导度与叶水势的关系; (2)基于气孔导度与水汽压亏缺的关系; (3)基于黎明前叶水势与中午叶水势的关系。之后, 从水力和碳经济性状两个方面比较分析了两种水分调节对策植物的种间差异。综合分析植物水分调节机制发现, 水力信号与化学信号的相互作用是植物水分调节行为的主控因素。最后提出3个亟待开展研究的问题: (1)针对不同地区开展植物水分关系相关性状的测定, 寻求可靠且普适的植物水分调节对策分类方法。(2)探索植物水分调节对策与水力、形态、结构、功能等性状之间的关联性, 为改进植被动态模型提供可靠的参数。(3)加深理解不同时空尺度上植物水分调节过程, 揭示植物对环境胁迫(尤其是干旱)的响应和适应机制。

关键词: 干旱胁迫, 木质部栓塞, 气候变化, 气孔调节, 水力失衡, 植物性状

Abstract:

Water is a vital resource for plant survival, growth and distribution, and it is of significance to explore mechanisms of plant water-relations regulation and responses to drought in ecophysiology and global change ecology. Plants adapt to different climates and soil water regimes and develop divergent water-regulation strategies involving a suite of related traits, of which two typical types are isohydric and anisohydric behaviors. It is critical to distinguish water-regulation strategies of plants and reveal the underlying mechanisms for plant breeding and vegetation restoration especially in xeric regions; and it is also important for developing more accurate vegetation dynamic models and predicting vegetation distribution under climate change scenarios. In this review, we first recalled the definitions of isohydric and anisohydric regulations and three quantitative classification methods that were established based on the relationships (1) between stomatal conductance and leaf water potential, (2) between stomatal conductance and vapor pressure deficit, (3) between predawn and midday leaf water potentials. We then compared the two water-regulation strategies in terms of hydraulics and carbon-economics traits. We synthesized the mechanisms of plant water-regulation and found that the interaction between hydraulic and chemical signals was the dominant factor controlling plant water-regulation behavior. Last, we proposed three promising aspects in this field: (1) to explore reliable and universal methods for classifying plant water-regulation strategies based on extensive investigation of the traits related with plant water-relations in various regions; (2) to explore relationships between plant water-regulation strategies and traits of hydraulics, morphology, structure, and function in order to provide reliable parameters for improving vegetation dynamic models; and (3) to deeply understand the processes of plant water-regulation at different spatial and temporal scales, and reveal mechanisms of plants’ responses and adaption to environmental stresses (especially drought).

Key words: drought stress, xylem embolism, climate change, stomatal regulation, hydraulic failure, plant trait