中文摘要：

利用光学显微镜对青藏高原29种草地双子叶植物叶片的气孔形态与数量特征进行观察及差异显著性分析,为揭示青藏高原草地双子叶植物对高原环境的适应机制及探索气孔作为辅助分类的依据奠定理论基础。结果表明：（1）青藏高原草地双子叶植物大多数种类在叶片上、下表皮均分布有气孔,气孔随机排列,气孔器多为无规则型。（2）气孔长度（SL）较小,上、下表皮的气孔平均长度分别为26.20μm与25.56μm,且气孔密度（SD）与气孔指数（SI）相对较大。（3）不同科、属、种间叶片上、下表皮的SL、SD、SI差异均极显著。（4）叶片上、下表皮的6个气孔数量特征之间具有显著相关关系。（5）上表皮的SL、SD与不同科、属、种间显著相关,下表皮除SI与物种间相关不显著外,其他指标与科、属、种间显著相关。研究认为,青藏高原草地双子叶植物独特的气孔形态与数量特征是对高寒极端环境长期适应的结果,且气孔数量特征对植物辅助分类具有重要价值。

英文摘要：

We investigated the leaf stoma morphology and quantitative characteristics of 29 dicotyledonous plants in the Tibetan Plateau grasslands by means of optical microscope and analyzed the significant difference among stoma index,which provided experimental basis for revealing the mechanism of adaptation to alpine environment and exploring auxiliary classification of stoma.The results showed that：（1） Most stoma randomly arranged on both upper and lower epidermis and stomatal apparatus was irregular type.（2） The average stomatal length（SL） of upper and lower epidermis were 26.20 μm and 25.56 μm,which was smaller,but stomatal density（SD） and stomatal index（SI） were relatively higher.（3） There were significant difference among various families,genera and species on SL,SD and SI.（4）There were significant correlation between six stomatal quantitative characteristics.（5） SL and SD of upper epidermis were significantly associated with families,genera and species.Other stomatal characteristics of lower epidermis except for SI were significant correlated with plant varieties.We came to the conclusion that the distinctive morphology and quantitative characteristics of leaf stoma of dicotyledonous plants in the Tibetan Plateau grasslands reflected the long-term adaptation to alpine environment and quantitative characteristics of stoma had important value in plant auxiliary classification.