CO_2浓度升高对湿地松针叶蒸腾特性和水分利用效率的影响  

Responses of Transpiration Characteristics and Water Use Efficiency of Pinus Elliottii Leaf to Elevated CO_2 Concentration

作　　者：龚伟[1] 宫渊波[1] 胡庭兴[1] 陈林武[2] 张发会[2] 王景燕[1] 朱志芳[2] 

机构地区：[1]四川农业大学生态林业工程省级重点实验室,四川雅安625014 [2]四川省林业科学研究院,四川成都610081

出　　处：《水土保持学报》2005年第5期178-182,共5页Journal of Soil and Water Conservation

基　　金：国家"十五"科技攻关项目:长江上游低山丘陵区水源涵养型植被建设技术研究与示范(2001BA510B02-03)部分内容;四川省森林培育重点学科建设项目

摘　　要：在不同CO2浓度下,测定了湿地松上年生针叶和当年生针叶净光合速率(Pn)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、气孔导度(Gs)和叶面饱和水汽压亏缺(Vpdl)随光照强度的变化。结果表明:Ci和Vpdl随光照强度增强而减小;Gs,Pn和Tr均随光照强度增强而增大,在达到光饱和点后Gs和Pn随光照强度增强而逐渐减小;WUE随光照强度增强呈先增大,达到最大值后又逐渐减小。Ci,Vpdl随CO2浓度升高而增大;Gs和Tr随CO2浓度升高而减小;Pn和WUE在CO2浓度为4001 200μmol/mol时随CO2浓度升高而增大,当CO2浓度升高至1 600μmol/mol时,Pn和WUE减小;同时,随着CO2浓度升高,上年生针叶光饱和点提高。To determine how transpiration characteristics and water use efficiency of Pinus elliottii respond to elevated CO2 concentrations, LI-6400 Portable Photosynthesis System was used to examine the changes of the net photosynthesis rate （Pn） , transpiration rate （Tr） , intercellular CO2 concentration （Ci） , stomatal conductance （Gs） and vapor deficit at the leaf surface （Vpdl） of 1-year-old leaf and 0-year-old leaf with light intensity under different CO2 concentration. The results showed that with enhanced light intensity, Ci and Vpdl decreased; Gs, Pn and Tr increased first, then Gs and Pn gradually decreased after leaf got to light saturation point ; WUE also increased first, but it gradually decreased after it reach max value. With elevated CO2 concentration, Ci and Vpdl increased ; Gs and Tr decreased ; Pn and WUE increased when CO2 concentration elevated from 400 to 1 200 μmol/ mol, but Pn and WUE decreased when CO2 concentration elevated to 1 600 μmol/mol ; at the same time, the light saturation point of 1-year-old leaf elevated.

关 键 词：湿地松 蒸腾特性 水分利用效率 CO2浓度升高 

分 类 号：S791.189[农业科学—林木遗传育种] Q945.1[农业科学—林学]