珍稀灌木绵刺与四合木光合特征的比较  

Comparative Study on Photosynthetic Characteristics of the Rare Shrubs Potaninia mongolica and Tetraena mongolicain Western Ordos

作　　者：张颖娟[1,2] 贾倩 马娟[1] ZHANG Ying-juan;JIA Qian;MA Juan(College of Life Science and Technology,Inner Mongolia Normal University,Hohhot 010022,China;Journal Editorial Department of Inner Mongolia Normal University,Hohhot 010022,China)

机构地区：[1]内蒙古师范大学生命科学与技术学院,呼和浩特010022 [2]内蒙古师范大学学报编辑部,呼和浩特010022

出　　处：《内蒙古大学学报（自然科学版）》2018年第6期629-636,共8页Journal of Inner Mongolia University：Natural Science Edition

基　　金：国家自然科学基金(31360140);内蒙古自然科学基金(2013MS0519)

摘　　要：为探讨自然生境下西鄂尔多斯强旱生小灌木绵刺(Potaninia mongolica Maxim)的光合生理生态适应性,以同生境珍稀植物四合木(Tetraena mongolica Maxim)做对照,通过对绵刺生长期、休眠期、复苏期光合作用的测定,结合当地气象资料探讨其光合特性.结果表明:(1)生长期和休眠期绵刺净光合速率(Pn)日变化呈"双峰"曲线,中午具有"光合下调"现象,主要受非气孔限制因素影响;下午Pn下降受气孔因素限制.复苏期呈"单峰"曲线,午后Pn降低受非气孔因素限制.(2)四合木光合日变化近似抛物线的"单峰"曲线,Pn降低受非气孔因素限制.(3)绵刺不同时期的蒸腾速率(Tr)、水分利用效率(WUE)、胞间CO2浓度(Ci)、气孔导度(Gs)等有明显的分异.(4)绵刺生长期与复苏期的光合气体交换参数(除Ci)均高于同期生长的四合木,单位时间内固定较多CO2,光合效率高.两种植物具有不同的生长适应模式,反映了荒漠植物与环境协同进化的生态适应性.绵刺较高的水分利用率是其对环境响应的适应机制.The photosynthesis and physio-ecological adaptability of Potaninia mongolica, the xerophytic shrubs in Western Ordos,were studies in current study. The photosynthetic characteristic parameters of P. mongolica and the diurnal photosynthesis changes in the growing, dormant and resurrection period were measured, which was compared with the endangered species Tetraena rn ongolica in the same habitat. The results showed that：l） Pn curve was double-peak in growing and dormant periods of P. mongolica. Pn exhibited so called ＂photosynthetic descent＂ in midday, be- cause of the non-stomata limitation. Pn decreased because of the stomatal limitation in the after- noon. In the resurrection period, Pn curve was single-peak and the stomata factor was determinant of photochemical decrease. 2） Pn curve was single-peak similar to parabola,and the photosynthetic rate decreased because of the stomata limitation of T. mongolica. 3） There were obvious differences of Tr value,WUE,Ci and Gs in different period of P. mongolica. 4） Besides Ci,the gas exchange pho- tosynthetic characteristic parameters in growing and resurrection period of P. rnongolica were higher than the T. mongolica in the same period,which fixed more CO2 per unit time and high photo- synthetic efficiency. In conclusion, the two plants had different growth adaptation patterns, which reflected the ecological adaptability of the desert plants in the course of cooperative evolution with the environment.

关 键 词：绵刺 珍稀灌木 光合作用 生态适应性 

分 类 号：Q945.11[生物学—植物学]