松嫩平原4种植物光合作用光响应特性的研究

在适宜的外界环境条件下设置11个光照梯度,对松嫩平原西部碱地上的芦苇、马莲、虎尾草和稗草植株叶片进行了光模拟试验。结果表明:改变光照强度对这4种植物叶片的光合作用、叶温、气孔导度、水分利用效率、蒸腾作用及胞间CO2浓度等生理指标有不同的影响。芦苇和马莲的光合速率与光合有效辐射强度呈明显的正相关关系,虎尾草和稗草的光合速率随光合有效辐射强度的增加出现先升高后降低的趋势;4种植物的叶温和蒸腾速率都随着光强的增加而升高,并且虎尾草和稗草的叶温始终高于芦苇和马莲;4种植物的胞间CO2浓度均随光强增加而下降;气孔导度与水分利用效率变化无规律性。

Study on Light Response of Photosynthesis in Leaves of Four Plants of Songnen Plain

A light simulation in-situ measurement for the leaves of Phragmites communis,Iris ensata Thunb,Cnloris vigata and Echinochloa crusgalli of the west alkaline district of Songnen plain was taken.The leaves of the four species were exposed in 11 intensities of illumination while other environmental conditions were the same.The result shows that the same intensity of illumination has different effects on physiologic indexes of these four species such as photosynthesis,leaf temperature,stomatal conductance,water use efficiency(WUE),transpiration and intercellular CO2 concentration(Ci).The net photosynthetic rate(Pn) of Phragmites communis and Iris ensata is positively correlated to the PAR.The Pn of Cnloris vigata and Echinochloa crusgalli increases at the beginning then decreases following the PAR.The leaf temperature and transpiration rate(Tr)of these four plants increase following the PAR.The leaf temperature of Cnloris vigata and Echinochloa crusgalli is higher than that of Phragmites communis and Iris ensata.The Ci decreases following the PAR.The variations of stomatal conductance and WUE are not regular to the PAR.