油松和侧柏的光合蒸腾特性及其与环境因子的关系  

Photosynthesis and Transpiration Characteristics of Pinus tabulaeformis and Platycladus orientalis and Their Relationship with Environmental Factors

作　　者：徐佳佳[1] 张建军[1] 王清玉[1] 李慧敏[1] 茹豪[1] 郭宝妮[1] 黄明[1] 

机构地区：[1]北京林业大学,北京100083

出　　处：《东北林业大学学报》2011年第7期15-18,共4页Journal of Northeast Forestry University

基　　金：国家"十二五"科技支撑项目(2011BAD38B06)

摘　　要：利用开放式气体交换Li—6400便携式光合作用测定系统对晋西黄土区油松和侧柏的光合、蒸腾特性进行了研究,并对净光合速率(Pn)、蒸腾速率(Tr)与其相关生理生态因子进行了简单相关性分析和通径分析。结果表明:油松和侧柏叶片的Pn日间均出现2个高峰;油松和侧柏叶片的Tr日间分别出现2个高峰、1个高峰;油松和侧柏叶片的水分利用效率(WU,E)日间均出现3个高峰。油松的Pn、WU,E日均值均高于侧柏,而Tr日均值则低于侧柏。光强(PA,R)、气孔导度(Gs)和胞间CO2摩尔分数(Ci)与Pn有极显著的相关性,其中影响油松和侧柏叶片光合的主要因子都是Gs和Ci,对油松的影响程度由大到小的顺序为Gs、Ci,对侧柏的影响程度由大到小的顺序为Ci、Gs;Tr与气孔导度(Gs)、光强(PA,R)、叶温(Ta)、相对湿度(RH)、水气压亏缺(Vp,d,l)有极显著的相关性,其中:Gs、Ta、RH是影响油松蒸腾作用的主要生理生态因子,影响程度由大到小的顺序为Gs、Ta、RH;PA,R、Ta和Vp,d,l是影响油松蒸腾作用的主要生理生态因子,影响程度由大到小的顺序为PA,R、Ta、Vp,d,l。An experiment was conducted to study the photosynthesis and transpiration characteristics of Pinus tabulaeformis and Platycladus orientalis in the Loess Plateau using the Li-6400 portable photosynthesis system. The correlation analysis and path analysis between net photosynthetic rate, transpiration rate and their related physiological and ecological factors were made respectively. The net photosynthetic rate of P. tabulaeformis and P. orientalis leaves showed two peaks during daytime. The transpiration rate of P. tabulaeformis and P. orientalis leaves manifested two peaks and one peak during daytime respectively. Three peaks of water use efficiency were observed in P. tabulaeformis and P. orientalis during daytime. The average diurnal net photosynthetic rate and water use efficiency of P. tabulaeformis were higher than those of P. orientalis, but the diurnal average transpiration rate of P. tabulaeformis was lower than that of P. orientalis. The diurnal variation of net photosynthetic rate of P. tabulaeformis and P. orientalis leaves had significant correlations with stomatal conductance, intercellular carbon dioxide concentration and light intensity. Stomatal conductance and intercellular carbon dioxide con- centration were the main factors affecting the net photosyuthetie rate of P. tabulaeformis and P. orientalis. The affecting ability of stomatal conductance on P. tabulaeformis was higher than that of intercellular carbon dioxide concentration, and the effect of intercellular carbon dioxide concentration on P. orientalis was more obvious than that of the stomatal conductance. The diurnal variation of transpiration rate of P. tabulaeformis aud P. orientalis leaves had significant correlations with stomatal conductance, light intensity, leaf temperature, relative humidity and vapor pressure deficit. Stomatal conductance, leaf temperature and relative humidity were the main physiological and ecological factors affecting transpiration rate of P. tabulaeformis. The stomatal conductance showed the greatest effect

关 键 词：油松 侧柏 净光合速率 蒸腾速率 

分 类 号：Q945.79[生物学—植物学]