北京引进树种火炬树和水曲柳的光合特征  

Study on eco-physiological characteristics of Rhus typhina and Fraxinus mandshurica in Beijing

作　　者：胡耀升[1] 刘艳红[1] 

机构地区：[1]北京林业大学森林培育与保护教育部重点实验室,100083

出　　处：《生态科学》2012年第4期377-383,共7页Ecological Science

基　　金：北京市科技计划项目"北京市重要植物种质资源调查;评价研究"(Z0850602970801);科学研究与研究生培养共建项目-科研基地(典型城市森林结构合理性研究)

摘　　要：应用LI-6400便携式红外气体分析仪,研究了北京市两种引进乔木生长旺季的光合作用的日变化规律和光响应曲线。结果表明:①水曲柳和火炬树的光合速率(Pn)、蒸腾速率(Tr)的日变化均为"双峰"曲线,而水分利用效率(WUE)的日变化为"单峰"曲线,但三者峰值出现的时刻和大小有所不同。②火炬树的光合速率(Pn)和水分利用效率(WUE)均高于水曲柳,但蒸腾速率(Tr)要低于水曲柳。③从光响应曲线来看,两种引进乔木均为阳生植物,其中火炬树对光的适应性范围较广,而水曲柳的耐阴性较强。④逐步回归分析表明:影响光合速率的主要因子是光合有效辐射、气孔导度、胞间CO2浓度。⑤与原产地进行对比可知:火炬树光合能力有所增加,水曲柳变化不大。研究认为,在北京,火炬树与水曲柳相比具有较强的竞争优势。研究结果可为首都园林绿化树种选择提供科学依据。By using LI-6400 CO2 gas analysis system, we studied the diurnal variations of photosynthetic rate and light curve of two introduction plants in Beijing. The results are summarized as follows. The curves of diurnal variation in Pn, Tr of Fraxinus mandshurica and Rhus phina leaves have two peaks while the curve of diurnal variation in WUE has one peak, but they have differences in the time and the value of the peaks occurred in terms of Pn, Tr, and WUE. The Pn and WUE for R. typhina are higher than those for E mandshurica. However, Tr is obviously lower in R. typhina than that in F mandshurica. Through the light curve of two introduction plants we can see that they are sun plants; besides R. typhina is broader in ecological adaptability for light, while F mandshurica has the high shade-tolerance. The major factors affecting the photosynthetic rate are the stomatal conductance, intercellular CO2 concentration and photosynthetic active radiation. By comparing the habitats we can see that photosynthetic capacity ofR. typhina has a rise while that ofE mandshuricajust has a little change. We can conclude that R. typhina has advantages in competition with E mandshurica in Beijing.

关 键 词：火炬树 水曲柳 光合特性 比较研究 

分 类 号：Q945.11[生物学—植物学]