Limited acclimation in leaf anatomy to experimental drought in tropical rainforest trees.
Limited acclimation in leaf anatomy to experimental drought in tropical rainforest trees.
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DOI：
10.1093/treephys/tpw078
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发表时间：
2016-12
期刊：
影响因子：
4
通讯作者：
Mencuccini M
中科院分区：
文献类型：
--
作者：
Binks O;Meir P;Rowland L;da Costa AC;Vasconcelos SS;de Oliveira AA;Ferreira L;Mencuccini M
据预测，在包括亚马逊河流域在内的一些热带地区，干旱期未来将变得更加频繁和严重，可能导致生产力下降、树木死亡率上升和储存碳排放增加。在热带地区进行了一项长期（12年）的穿透性降雨排除（TFE）实验，通过检查以下叶片特征，我们检验了树木产生适应于科普更高水平水分胁迫的叶片的假设：面积、厚度、单位面积叶重、叶脉密度、气孔密度、栅栏叶肉厚度、海绵叶肉厚度和两层表皮厚度，气孔体积和栅栏和海绵叶肉的平均细胞大小。我们还测试叶片解剖的差异是否与观察到的差异干旱诱导的死亡率的反应类群之间是一致的，并寻找叶片解剖，叶水关系和气体交换参数之间的关系。我们的数据表明，树木不产生叶片，更旱型响应12年的土壤水分亏缺。然而，干旱处理确实导致近轴表皮厚度（TFE：20.5 ± 1.5 µm，对照：16.7 ± 1.0 µm）和内腔体积（TFE：2.43 ± 0.50 mm3 cm−2，对照：1.77 ± 0.30 mm3 cm−2）增加。抗旱性和干旱敏感类群之间没有一致的差异，虽然干旱敏感性状态和干旱处理之间发生的栅栏叶肉厚度（P = 0.034）和叶腔体积（P = 0.025）的相互作用。对水分亏缺的有限反应可能反映了叶片形态、水分关系和光合特性之间的紧密协调。这表明，在这些方面的植物解剖在这些类群中的可塑性很小，和叶性状的表型可塑性可能不会促进亚马逊河流域树木的驯化，以预测未来减少旱季水的可用性。
Dry periods are predicted to become more frequent and severe in the future in some parts of the tropics, including Amazonia, potentially causing reduced productivity, higher tree mortality and increased emissions of stored carbon. Using a long-term (12 year) through-fall exclusion (TFE) experiment in the tropics, we test the hypothesis that trees produce leaves adapted to cope with higher levels of water stress, by examining the following leaf characteristics: area, thickness, leaf mass per area, vein density, stomatal density, the thickness of palisade mesophyll, spongy mesophyll and both of the epidermal layers, internal cavity volume and the average cell sizes of the palisade and spongy mesophyll. We also test whether differences in leaf anatomy are consistent with observed differential drought-induced mortality responses among taxa, and look for relationships between leaf anatomy, and leaf water relations and gas exchange parameters. Our data show that trees do not produce leaves that are more xeromorphic in response to 12 years of soil moisture deficit. However, the drought treatment did result in increases in the thickness of the adaxial epidermis (TFE: 20.5 ± 1.5 µm, control: 16.7 ± 1.0 µm) and the internal cavity volume (TFE: 2.43 ± 0.50 mm3 cm−2, control: 1.77 ± 0.30 mm3 cm−2). No consistent differences were detected between drought-resistant and drought-sensitive taxa, although interactions occurred between drought-sensitivity status and drought treatment for the palisade mesophyll thickness (P = 0.034) and the cavity volume of the leaves (P = 0.025). The limited response to water deficit probably reflects a tight co-ordination between leaf morphology, water relations and photosynthetic properties. This suggests that there is little plasticity in these aspects of plant anatomy in these taxa, and that phenotypic plasticity in leaf traits may not facilitate the acclimation of Amazonian trees to the predicted future reductions in dry season water availability.
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DOI：
10.1111/nph.13927
发表时间：
2016-07
期刊：
The New phytologist
影响因子：
--
作者：
Binks O;Meir P;Rowland L;da Costa AC;Vasconcelos SS;de Oliveira AA;Ferreira L;Christoffersen B;Nardini A;Mencuccini M
通讯作者：
Mencuccini M
影响因子：
7.3
作者：
Buckley, Thomas N.
通讯作者：
Buckley, Thomas N.
影响因子：
2.6
作者：
Boughalleb, Faycal;Hajlaoui, Hichem
通讯作者：
Hajlaoui, Hichem
影响因子：
2.7
作者：
Allen, Craig D.;Breshears, David D.;McDowell, Nate G.
通讯作者：
McDowell, Nate G.
影响因子：
30.7
作者：
Boisier, Juan P.;Ciais, Philippe;Guimberteau, Matthieu
通讯作者：
Guimberteau, Matthieu