兰州市南北两山三种绿化树种光合特性研究  

Research on photosynthesis characteristics of three tree species in the mountains adjacent to Lanzhou City

作　　者：杨占彪[1] 蒋志荣[1] 柴薇薇[1] 李禄军[1] 

机构地区：[1]甘肃农业大学林学院,甘肃兰州730070

出　　处：《甘肃农业大学学报》2006年第5期85-90,共6页Journal of Gansu Agricultural University

摘　　要：利用LI-6200便携式光合测定仪(美国)对兰州市南北两山侧柏、油松、柽柳等3种绿化树种在自然条件下的光合速率(Pn)、蒸腾速率(E)、气孔导度(Gs)、光合有效辐射(PAR)、空气相对湿度(RH)、大气温度(T)和水分利用效率(WUG)进行了测定.结果表明,侧柏、油松、柽柳的光合日进程均呈“双峰”曲线,出现明显的光合“午休”现象;气孔导度日变化曲线呈“W”型;蒸腾速率呈单峰;水分利用率最高值出现在上午较早时分.对3种树的光合速率和蒸腾速率与影响因子进行相关分析及逐步回归分析表明,各树种光合速率和蒸腾速率的回归方程分别为,侧柏:Pn=0.006PAR+1.176RH,E=1.120T;油松:Pn=0.010PAR,E=1.004T+0.482RH;柽柳:Pn=0.015PAR,E=0.757T+0.566RH-8.397Gs.对植物光合速率和蒸腾速率影响程度最大的因子主要是光合有效辐射和空气相对湿度,因此在干旱季节进行灌溉时,应选择喷灌,提高空气相对湿度,减少植物的蒸腾速率.Photosynthetic rate （P.）, transpiration rate （E）, stomata conductance （Gs）, active photosynthetic radiation（PAR））,relative air humidity（RH）,air temperature（T） and water use efficiency（WUG） of three tree species Platycladus orientalis, Pinus tabulaeformis, Tamarix chinensis were measured with a portable LI-6200 gas analysis system under natural conditions in the mountains adjacent to Lanzhou City. The results showed that net photosynthetic rate in the leaves for three species appeared in curvilinear chan- ges with double peaks and apparent middy depression diurnally,that of stomata conductance displayed “W” pattern and that of transpiration rate a single-peak pattern. The highest water use efficiency occurred in the early morning. The correlation analysis and stepwise regression between physiological characteristics of three species and environmental factors showed that the regression equation of Platycladus orientalisbetween photosynthetic rate, transpiration rate and the environment factor was （Pn）= 0. O06PAR ＋ 1. 176RH,E=1. 120T;the regression equation of Pinus tabulaeformis was （Pn）=0. OIOPAR,E=1.004T＋0. 482RH;the regression equation of Tamarix chinensis was （Pn）=0. 015PAR,E=0.757T＋0. 566RH-8. 397Gs. The most important effective factors to photosynthetic rate and transpiration rate were PAR and RH. That inquires to use sprinkler irrigation in arid season to improve humid in air and descend transpiration rate. As a result,it can sustain the water in plants.

关 键 词：光合速率 蒸腾速率 水分利用率 日变化 回归分析 

分 类 号：Q945.11[生物学—植物学]