我国北方树种水力结构特征与木质部栓塞日变化规律研究  

Discussion on the Daily Change of Hydraulic Architecture Characteristics and Xylem Embolism of Some Trees Species in North China

作　　者：刘晓燕 李吉跃[2] 

机构地区：[1]北京市丰台区林业工作站,北京100071 [2]华南农业大学,广东广州510642

出　　处：《安徽农学通报》2009年第11期70-75,共6页Anhui Agricultural Science Bulletin

基　　金：国家自然科学基金项目(30070637);教育部高等学校博士点基金资助;骨干教师资助项目

摘　　要：在北京林业大学校园内选取侧柏、刺槐等11个针阔叶树种为研究对象,用改良的冲冼法测定各树种1 a生枝条小枝水势、水力结构参数及木质部栓塞的日变化。结果表明:各树种1 a生枝条导水率与比导率的日变化趋势相似,均表现为早晚高,上下午低。而各树种木质部栓塞程度的日变化情况与水力结构参数的日变化趋势相反,表现出早晚低,上下午高的单峰型变化趋势。从材性上看,针阔叶树种导水率和比导率的日变幅大小为:环孔材树种>散孔材树种>无孔材树种,而木质部栓塞的脆弱性大小也依次为:环孔材树种>散孔材树种>无孔材树种。Ten trees species： Platycladus ofientalis, Acer trnncatum etc. were selected on the campus of the Beijing Forestry University. The daily change of water potential, hydraulic architecture parameters and xylem embolism of one - year - old twigs were measured by improved flushing method. The results show that the daily change law of hydraulic conductivity is resembled to that of special conductivity, being higher in early rooming and night than that in forenoon and afternoon. However, The daily change of xylem embolism is reversed to that of hydraulic architecture parameters, being lower in early morning and night than that in forenoon and afternoon. As for as characteristic of vessels and tracheids are concerned, the daily change ranges of hydraulic conductivity and special conductivity in experimented trees species are ring - porous species 〉 diffuse - porous species 〉 none - porous species. The daily change ranges of xylem embolism are also ring - porous species 〉 diffuse - porous species 〉 none - porous species.

关 键 词：水力结构 日变化 栓塞 导水率 比导率 

分 类 号：Q149[生物学—生态学]