马占相思叶片液汁碳同位素甄别率和水分利用效率

被引：8

作者：

孙谷畴

赵平

蔡锡安

曾小平

刘晓静

饶兴权

王华

机构：

[1] 中国科学院华南植物园鹤山丘陵综合试验站

来源：

生态学杂志 | 2008年 / 04期

基金：

广东省自然科学基金;

关键词：

碳同位素甄别率; 水分利用效率; 叶片液汁光合产物;

D O I：

10.13292/j.1000-4890.2008.0122

中图分类号：

Q945 [植物生理学];

学科分类号：

0903 ;

摘要：

利用PMS压力室压取叶片液汁并借助稳定碳同位素质谱仪测定碳同位素比率,分析了马占相思(Acacia mangium)叶片液汁光合产物的甄别率(Δ)和估测了水分利用效率。结果表明:阴天马占相思林冠层日平均空气CO2的碳同位素比率(δa)为-7.57‰±1.41‰,晴天则为-8.54‰±0.67‰;阴天叶片液汁的光合产物碳同位素比率(δp)日变化呈鞍型,而晴天则从早上至黄昏逐步降低;晴天δp与叶片/空气水汽压亏缺(D)明显呈负相关,阴天的δp变化相对较小;δp随叶片水势(Ψ)降低而降低,显示水分胁迫引起δp降低;叶片液汁的D和经气体交换法获得的细胞胞间(Pi)和外界(Pa)CO2分压之比呈正相关,测定结果与理论上碳同位素相关扩散和生化分馏相一致。分析结果显示,田间马占相思空气CO2经气孔扩散的稳定同位素效应a=4.6‰,有关Pi的净固定的稳定碳同位素效应b=28.2‰。认为液汁碳同位素甄别率是外围空气CO2进入光合产物的净甄别率,由叶片液汁Δ估测的水分利用效率与气体交换法所得结果相一致(R2=0.86,P<0.001)。本文所采用的叶片液汁光合产物测定即时Δ以及计算水分利用效率的方法,可减少田间条件下环境因素明显变化对水分和碳同位素的影响,该方法有助于进一步开展由植株至冠层扩展的碳和水分平衡的生理生态研究。

引用

页码：497 / 503

页数：7

共 28 条

[1]

Stomatal response to humidityin common bean(Phaseolus vulgaris):Implication formaximum transpiration rate,water use efficiency and pro-ductivity. Comstock J,Ehleringer J. Australian Journal Plant Physiology . 1993

[2] CAPE GRIM ISOTOPE MEASUREMENTS - A PRELIMINARY ASSESSMENT [J].

FRANCEY, RJ .

JOURNAL OF ATMOSPHERIC CHEMISTRY, 1985, 3 (02) :247-260

[3]

An Introduction of Environ-mental Biophysics. Campbell GS,Norman JM. . 1998

[4]

Carbon isotope discrimination and photosynthesis. Farquhar G D,Ehleringer J R,Hubick K T. Annual Review of Plant Physiology . 1989

[5]

Correlation between carbonisotope ratio and micro-habitat in desert plants. Ehleringer JR,Cooper TA. Oecologia . 1986

[6]

Carbon-13variations in plants and the relation-ship between carbon-13and carbon-14variations in nature. Craig H. Journal of Geophysical Research . 1954

[7]

Carbon isotopediscrimination measured concurrently with gas exchange toinvestigate CO2diffusion in leaves of higher plant. Evans JR,,Sharkey TD,Berry JA,et al. Austral-ian Journal ofPlant Physiology . 1986

[8]

Corre-lation between the carbon isotope discrimination in leafstarch and sugars of C3plants and the ratio of intercellularand atmospheric partial pressured of carbon dioxide. Brugnoli E,,Hubick KT,von Caemmerer S,et al. Plant Physiology . 1988

[9]

Cape Gm isotope measurements:A prelimi-nary assessment. Francey RT. Journal of Atmospheric Chemistry . 1985

[10]

Importance of short-term dynamics in carbon isotope ratio of ecosystem respira-tion(δ13CR)in Mediterranean oak woodland and linkage toenvironmental factors. Werner C,Unger S,Pereir J,et al. NewPhytologist . 2006

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