Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China.
Water Management and Systems Research Unit, USDA-ARS, Fort Collins, CO 80526, USA.
Sci Adv. 2019 Feb 13;5(2):eaav1332. doi: 10.1126/sciadv.aav1332. eCollection 2019 Feb.
Water must be transported long distances in tall plants, resulting in increasing hydraulic resistance, which may place limitations on the maximum plant height ( ) in a given habitat. However, the coordination of hydraulic traits with and habitat aridity remains poorly understood. To explore whether modifies the trade-off between hydraulic efficiency and safety or how water availability might influence the relationship between and other hydraulic traits, we compiled a dataset including and 11 hydraulic traits for 1281 woody species from 369 sites worldwide. We found that taller species from wet habitats exhibited greater xylem efficiency and lower hydraulic safety, wider conduits, lower conduit density, and lower sapwood density, which were all associated with habitat water availability. Plant height and hydraulic functioning appear to represent a single, coordinated axis of variation, aligned primarily with water availability, thus suggesting an important role for this axis in species sorting processes.
在高大的植物中，水必须被长距离运输，从而导致水力阻力不断增加，这可能会限制给定栖息地中植物的最大高度。然而，水力特征与 和生境干旱之间的协调仍然知之甚少。为了探讨 是否改变了水力效率和安全性之间的权衡，或者水分供应情况如何影响 和其他水力特征之间的关系，我们编译了一个数据集，其中包括来自全球 369 个地点的 1281 种木本植物的 和 11 个水力特征。我们发现，来自湿润生境的较高物种表现出更高的木质部效率和更低的水力安全性、更宽的导管、更低的导管密度和更低的边材密度，所有这些都与生境水分供应有关。植物高度和水力功能似乎代表了一个单一的、协调的变异轴，主要与水分供应有关，因此表明该轴在物种分类过程中起着重要作用。
