LONG-TERM RELATIONSHIPS AMONG ATMOSPHERIC CO2, STOMATA, AND INTRINSIC WATER USE EFFICIENCY IN INDIVIDUAL TREES
LONG-TERM RELATIONSHIPS AMONG ATMOSPHERIC CO2, STOMATA, AND INTRINSIC WATER USE EFFICIENCY IN INDIVIDUAL TREES
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DOI：
10.3732/ajb.0800410
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发表时间：
2009-10-01
影响因子：
3
通讯作者：
Mukunda, Sharda
中科院分区：
文献类型：
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作者：
Miller-Rushing, Abraham J.;Primack, Richard B.;Mukunda, Sharda
叶片水平对大气二氧化碳（CO2）浓度增加的反应可能对水和碳循环产生重大影响。我们调查了是否气孔密度，保卫细胞长度，和内在水分利用效率（iWUE）的27个单独的树木生长在阿诺德植物园在波士顿。在过去的100年里，马萨诸塞州对不断变化的环境条件做出了反应。我们研究了从1893年到2006年收集的74个标本馆标本，从三个属-槭（枫树），栎（橡树），鹅耳枥属（角树）。在此期间，全球平均大气CO2浓度增加了约29%（86 ppm），波士顿的气温上升了1.8摄氏度。气孔密度与保卫细胞长度呈负相关。虽然气孔密度下降，保卫细胞长度随着时间的推移而增加，这些变化并不依赖于CO2浓度的变化幅度。内在WUE没有随时间变化显着。我们的研究结果表明，iWUE可能不会响应CO2浓度的变化，在个别树木的生命周期，可能是因为补偿气孔密度和保卫细胞大小的变化。我们提供了一个方法的例子，可以使研究人员区分遗传和塑料对长寿树木的全球变化的反应。
Leaf-level responses to increases in atmospheric carbon dioxide (CO2) concentrations could have large implications for water and carbon cycles. We investigated whether stomatal density, guard cell length, and intrinsic water use efficiency (iWUE) of 27 individual trees growing at the Arnold Arboretum in Boston. Massachusetts have responded to changing environmental conditions over the last 100 years. We examined leaves from 74 herbarium specimens collected from three genera-Acer (maples), Quercus (oaks), and Carpinus (hornbeams)-from 1893 to 2006. During this period, global average atmospheric CO2 concentrations increased by approximately 29% (86 ppm), and temperatures in Boston increased by 1.8 degrees C. Stomatal density and guard cell length were negatively correlated in oaks and hombeams. Although stomatal density declined and guard cell length increased over time, the changes were not dependent on the magnitude of changes in CO2 concentrations. Intrinsic WUE did not change significantly over time. Our findings suggest that iWUE may not respond to changes in CO2 concentrations over the lifetimes of individual trees, possibly because of compensating changes in stomatal density and guard cell size. We provide an example of a method that can enable researchers to differentiate between genetic and plastic responses to global change in long-lived trees.