CO_2摩尔分数升高对兴安鹿蹄草光合生理特性的影响  

Effects of Elevated CO_2 Concentration on Photosynthetic Physiological Characteristics of Pyrola dahurica(H.Andr.) Kom.

作　　者：崔大练[1] 马玉心[1] 蔡体久[2] 

机构地区：[1]浙江海洋学院,舟山316000 [2]东北林业大学

出　　处：《东北林业大学学报》2013年第1期94-99,共6页Journal of Northeast Forestry University

基　　金：国家星火计划(2011GA700182)

摘　　要：兴安鹿蹄草是北方针阔混交林的指示植物,对CO2的升高敏感而直接。在人工控制CO2摩尔分数梯度条件下,分别测量了兴安鹿蹄草老叶与新叶从4—9月份的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和叶面饱和蒸气压亏缺(Vp,d,l)对连续CO2摩尔分数增大的响应。结果表明:兴安鹿蹄草老叶与新叶随着CO2摩尔分数的升高其净光合速率也随之升高,兴安鹿蹄草老叶的CO2饱和点为1 300μmol.mol-1,新叶的CO2饱和点为700μmol.mol-1;5月份的净光合速率明显高于4、6月份的,6—9月份兴安鹿蹄草新叶净光合速率差异不显著。兴安鹿蹄草老叶与新叶在不同月份随着胞间CO2摩尔分数的升高,气孔导度呈现不同的变化规律,蒸腾速率的大小与气孔导度的大小呈显著的正相关;各个月份兴安鹿蹄草叶片饱和蒸汽压亏缺几乎不随胞间CO2摩尔分数的变化而变化,但各个月份差异较大;兴安鹿蹄草老叶与新叶在各个月份随着CO2摩尔分数的升高水分利用效率(WU,E)都表现出逐渐增高的趋势,其中5月份的WU,E明显高于其他各个月份的。Pyrola dahurica （ H. Andr. ） Kom. is an indicative plant of broad-leaved mixed forest in the north, and sensitive to the increase of CO2. Under artificial control of COz mole fraction gradient, we measured the net photosynthetic rate （ Pn ） , transpiration rate （ Tr） , stomata] conductance （G） and leaf the surface saturated vapor pressure deficit （ Vp, d, ） in old ]eaves and new ]eaves as a response to continuous increase of CO2 mole fraction from April to September. The results showed that ： the net photosynthetic rate increases with the increase of CO2 mole fraction in old leaves and new leaves of P. dahurica. The CO2 saturation point is 1 300/.Lmo[ ~ tool-1 in old [eaves and 700 I^mo] ~ tool-1 in new leaf of P. dahurica. The net photosynthetic rate in May is significantly higher than that in April and June. The difference of the net photosyn- thetic rate is not significant in new leaf from June to September. Stomata] conductance in old and new leaves presents a dif- ferent variation with intercellular CO2 mole fraction increasing in different months, and the size of the transpiration rate has positive correlation with the size of stomata] conductance significantly. The wane of leaves saturation vapor pressure deficit almost is not various with the ceil intercellular CO2 mole fraction in different months, but the difference of each month is quite different. The water use efficiency （ Wu, E ） shows a trend of gradual increasing with the increase of CO2 mole fraction in old leaves and new leaves in different months, and the water use efficiency （ WU, E ） in May is significantly higher than that in other months.

关 键 词：兴安鹿蹄草 光合特性 CO2胁迫 

分 类 号：Q945.75[生物学—植物学]