Study on Light Response of Shepherdia argentea and Hippophae thamnoides Seedlings under Different Soil Moisture Conditions
In alpine region of Loess Plateau, by using Li-6400 portable photosynthesis system, light response of gas exchange parameters in S. argentea and H.rhamnoides seedlings under different soil moisture conditions was analyzed. The results showed that Pn. Tr and WUE of the two shrub species were both increased with an increase of the PAR. With continued increase of the PAR. Pn and WUE of S. argentea and H.rhamnoides seedlings declined but Tr still increased. With the increase of soil water content (SWC), Pn, Tr of both two shrub species increased. while WUE increased first. then declined after arriving at the maximum under mild water stress condition (W2). When SWC was in the same, light compensation point (LCP) of S. argentea was lower than that of H.rhamnoides obviously, light saturation point (LSP) and efficiency of light energy utilization of S. argentea were higher than those of H. rhamnoides. and the apparent quantum yield (α) in the leaves of S.argentea was higher than that of H.rhamnoides. So, compared with H.rhamnoides, photosynthetic capacity of S.argentea was stronger at low PAR. Contrastive analysis indicated that under severe water stress condition (W4) H.rhamnoides was easier to be stressed by high PAR. The capacity utilization ratio of low PAR and WUE in S. argentea was higher than that of H.rhamnoides. Thus, it is concluded that the drought-tolerant productivity of S. argentea seedlings was stronger than that of H.rhamnoides seedlings.
net photosynthesis rates transpiration rate water use efficiency light response
Han Luo Mei Dong Jing Qin Kangning He Yiyuan Zhang Anchao Li
College of Soil and Water Conservation,Beijing Forestry University, Beijing 100083,China
国际会议
西安
英文
465-469
2010-10-11（万方平台首次上网日期，不代表论文的发表时间）