欢迎访问《草业学报》官方网站,今天是 分享到:

草业学报 ›› 2018, Vol. 27 ›› Issue (7): 36-46.DOI: 10.11686/cyxb2017505

• 研究论文 • 上一篇    下一篇

东达山高寒草甸8种植物气孔特征沿土壤水分梯度的变化

张大才*, 朱玉怀, 李双智   

  1. 西南林业大学林学院,云南 昆明 650224
  • 收稿日期:2017-12-13 修回日期:2018-03-02 出版日期:2018-07-20 发布日期:2018-07-20
  • 通讯作者: *
  • 作者简介:张大才(1977-),男,四川平昌人,副教授。E-mail: dczhang24@163.com
  • 基金资助:
    国家自然科学基金(31660054)和西南林业大学林学一级学科建设项目资助

Variation in stomatal characteristics of eight plant species along a soil moisture gradient in alpine meadow of the Dongda Mountains in southeast Tibet

ZHANG Da-cai*, ZHU Yu-huai, LI Shuang-zhi   

  1. Faculty of Forestry, Southwest Forestry University, Kunming 650224, China
  • Received:2017-12-13 Revised:2018-03-02 Online:2018-07-20 Published:2018-07-20
  • Contact: *

摘要: 植物叶片气孔密度和大小具有可塑性,在外界胁迫下而变化,是植物适应环境变化的重要机制。为揭示高寒草甸生境趋向干旱化过程中植物气孔特征的变化规律,选择藏东南东达山高寒草甸的8种优势或常见植物作为研究对象,设置10个土壤水分梯度,分析气孔特征的变化。结果表明,根据植物对土壤水分的依赖程度可划分为4种类型:大花嵩草为沼生型,随土壤干旱程度的增加气孔密度增加、气孔大小减小;鸭跖草、小大黄、矮生嵩草和珠芽蓼为湿生型,气孔密度和大小与土壤含水率之间的关系多呈现为单峰曲线格局;圆穗蓼和线叶嵩草为旱生型,气孔特征随土壤干旱程度增加的变化趋势与沼生型植物几乎相反;高山嵩草气孔特征与土壤含水率之间的相关性不显著,在土壤水分梯度上分布范围广,为广布型。每种植物生长都有适宜的土壤水分条件,过高或过低的土壤含水率都将胁迫植物的生长,因此植物气孔特征与土壤含水率之间的关系呈现多种变化格局。

关键词: 气孔密度, 保卫细胞, 嵩草属, 高寒草甸, 水分梯度

Abstract: The density, length and width of stomata are plastic, and these traits can vary with the degree of external stress, and thereby provide an important mechanism for adaptation to variation in environmental factors. In order to survey the typical changes in stomatal characteristics across a moisture deficit gradient in an alpine meadow, eight dominant or common plant species of the alpine meadow in southeast Tibet, were chosen for study, and sites representing a ten-step gradient in soil moisture were identified. The results indicated there are 4 types, based on the degree of water dependency. Kobresia macrantha belonged to a helophyte type, and its stomatal density increased with decreasing soil moisture, but stomatal length and guard cell width decreased. Commelina communis, Rheum pumilum, Kobresia humilis and Polygonum viviparum were a ‘high moisture environment’ type, and the variation in stomatal density, length and guard cell width was typically unimodal across the soil moisture gradient studied. Polygonum macrophyllum and Kobresia capillifolia were species of drier environments, and the variation of stomatal density, length or guard cell width was almost opposite to that of the helophyte type. Stomatal characteristics of Kobresia pygmaea, were not significantly related with soil moisture, and it had a wide distributional range along the soil moisture gradient, hence it is a widely adapted type. Each plant species had its own soil moisture optimum, with growth stress evident at higher or lower soil moisture. In summary, numerous relationships between stomatal characteristics and soil moisture were elucidated.

Key words: stomatal density, guard cells, Kobresia, alpine meadow, gradient of moisture