叶片结构的水力学特性对植物生理功能影响的研究进展

Research progress in the effects of leaf hydraulic characteristics on plant physiological functions

叶片是植物进行光合、呼吸、蒸腾作用的主要器官,早期的研究主要集中于水分在叶片中的运输路径,而对叶脉结构及其生态学意义研究甚少。近年来关于叶片叶脉结构、气孔结构的功能及叶片水力学特性的意义研究已经成为植物生理生态的研究热点。该文综述了叶脉的结构性状的指标(叶脉密度、直径、间距等),叶片水力学结构特性对植物生长、水分运输、气体交换、光合作用等生理功能的影响,及其与植物对干旱适应性之间的关系。叶脉结构是决定叶片生理功能的基础,因此在未来的工作中应分析比较不同种类植物叶脉结构形态与导水、光合、呼吸、同化作用之间的关系,建立植物茎干-枝-叶系统水力传导的机理性模型,用以探索不同植物功能结构和高效用水生理生态学机制,据此评估不同种类植物在未来气候情景下的地位。

Leaf is the main organ for plant photosynthesis, respiration, and transpiration. Earlier studies mainly focused on water transportation pathway in leaves, but leaf vein architecture and its ecological significance have been rarely studied. Recently, studies of leaf vein architecture, functions of stomatal structure, and leaf hydraulic characteristics have become major focuses of plant ecological research. This paper reviews the index of leaf vein architectural traits（i.e., vein density, diameter, and distance between veins）, the influence of leaf hydraulic characteristic on plant functions such as growth, water transportation, gas exchange, and the relationship between leaf hydraulic conductance and drought adaptability for plants. Leaf vein architecture is the foundation of leaf physiological functions, and future studies should explore various types of relationships between plant leaf vein architectural traits and functional characteristics such as hydraulic conductance, photosynthesis, and respiration. Future research might also aim at development of stem-branch-leaf continuum model to explore ecophysiological mechanisms of plant functional structures and efficiency of water transportation, and to assess the adaptation of plants to the future climate scenarios.