Winkel Anders, Visser Eric J W, Colmer Timothy D, Brodersen Klaus P, Voesenek Laurentius A C J, Sand-Jensen Kaj, Pedersen Ole
School of Plant Biology, The University of Western Australia, Crawley, 6009, Western Australia, Australia.
Freshwater Biological Laboratory, Department of Biology, University of Copenhagen, Universitetsparken 4, 3rd floor, 2100, Copenhagen, Denmark.
Plant Cell Environ. 2016 Jul;39(7):1537-48. doi: 10.1111/pce.12717. Epub 2016 May 12.
Traits for survival during flooding of terrestrial plants include stimulation or inhibition of shoot elongation, aerenchyma formation and efficient gas exchange. Leaf gas films form on superhydrophobic cuticles during submergence and enhance underwater gas exchange. The main hypothesis tested was that the presence of leaf gas films influences the distribution of plant species along a natural flood gradient. We conducted laboratory experiments and field observations on species distributed along a natural flood gradient. We measured presence or absence of leaf gas films and specific leaf area of 95 species. We also measured, gas film retention time during submergence and underwater net photosynthesis and dark respiration of 25 target species. The presence of a leaf gas film was inversely correlated to flood frequency and duration and reached a maximum value of 80% of the species in the rarely flooded locations. This relationship was primarily driven by grasses that all, independently of their field location along the flood gradient, possess gas films when submerged. Although the present study and earlier experiments have shown that leaf gas films enhance gas exchange of submerged plants, the ability of species to form leaf gas films did not show the hypothesized relationship with species composition along the flood gradient.
陆生植物在洪水期间的生存特征包括对茎伸长的刺激或抑制、通气组织的形成以及高效的气体交换。在淹没期间，叶气膜在超疏水角质层上形成，增强水下气体交换。所检验的主要假设是叶气膜的存在影响植物物种沿自然洪水梯度的分布。我们对沿自然洪水梯度分布的物种进行了实验室实验和实地观察。我们测量了95个物种叶气膜的有无以及比叶面积。我们还测量了25个目标物种在淹没期间的气膜保留时间以及水下净光合作用和暗呼吸。叶气膜的存在与洪水频率和持续时间呈负相关，在很少被洪水淹没的地点，拥有叶气膜的物种比例最高可达80%。这种关系主要由禾本科植物驱动，所有禾本科植物无论在洪水梯度上的田间位置如何，在淹没时都具有气膜。尽管本研究和早期实验表明叶气膜增强了淹没植物的气体交换，但物种形成叶气膜的能力与沿洪水梯度的物种组成并未呈现出假设的关系。
