沙柳、黄柳和杞柳光合作用的日变化  

Daily Dynamics of Photosynthetic Characteristics of Three Species of Salix

作　　者：孔蓓蓓[1] 刘超[1] 尹伟伦[1] 夏新莉[1] 

机构地区：[1]北京林业大学生物科学与技术学院,北京100083

出　　处：《河南科技大学学报（自然科学版）》2009年第3期79-83,共5页Journal of Henan University of Science And Technology:Natural Science

基　　金：国家"十一五"科技支撑计划项目(2006BAD03A01);北京市教育委员会学科建设与研究生培养项目资助

摘　　要：利用Li-6400光合仪对沙柳、黄柳和杞柳3种杨柳科植物的光合作用日变化进行了研究。结果表明:(1)3种柳树的净光合速率Pn,蒸腾速率Tr,气孔导度Gs的日变化均为"双峰"型曲线,峰值出现在10:00和14:00点,12:00点左右存在明显的"午休"现象,但不同柳树Pn,Tr,Gs的高峰和谷底的高低不同。(2)3种柳树的WUE日变化均呈"双峰"曲线,8:00达到第一峰,之后逐渐降低,黄柳、杞柳在12:00点降到谷底,14:00达到第二峰,沙柳在14:00点降到谷底,16:00达到第二峰,峰值不明显。(3)根据Pn,Ci,Ls的变化方向,推测3种柳树的光合"午休"主要受气孔因素限制。(4)相关分析结果表明,对Pn影响最显著的因子是PAR,其次是Gs,Ci,Ta,RH;对Tr影响最显著的因子是PAR,其次是Ci,Ta,RH,Gs。Daily dynamics of photosynthetic characteristics in Salix purpurea,Salix psammophi and Salix gordejevii were monitored using Portable Li-6400 photosynthesis system.The results were summarized as follows:①The curves of diurnal variation in Pn,Tr and Gs of three species of Salix varieties leaves had two peaks at 8:00 o′clock and 10:00 o′clock,and an obvious midday depression at 12:00 o′clock,althought three species of Salix were different in the time and the value of the peaks which occurred in terms of Pn,Tr and Gs.②WUE had two peaks in all three species of Salix,they reached the highest balue of WUE at 8:00 o′clock and then decreased gradually.The value of Salix psammophi and Salix gordejevii reduced to minimum at 12:00 o′clock and second peak appeared at 14:00 o′clock.The WUE value of Salix purpurea reduced to minimum at 14:00 o′clock and second peak appeared at 16:00 o′clock.③The mindday depression in three species of Salix was controlled by stomatal factor according to the tendency of changes in Pn,Gi,Ls.④Correlation analyses showed that the factors affecting Pn could be ranked,from the highest to the lowest,as PAR>Gs> Gi>Ta>RH,and the factors affecting Tr could be ranked as PAR>Gi>Ta>RH>Gs.

关 键 词：柳树 净光合速率 光合日变化 

分 类 号：S718.45[农业科学—林学] Q945.79[生物学—植物学]