Data from: More than iso/anisohydry: hydroscapes integrate plant water‐use and drought tolerance traits in ten eucalypt species from contrasting climates

The iso/anisohydric continuum describes how plants regulate leaf water potential and is commonly used to classify species drought response strategies. However, drought response strategies comprise more than just this continuum, incorporating a suite of stomatal and hydraulic traits. Using a common garden experiment, we compared and contrasted four metrics commonly used to describe water use strategy during drought in ten eucalyptus species comprising four major ecosystems in eastern Australia. We examined the degree to which these metrics were aligned with key stomatal and hydraulic traits related to plant water use and drought tolerance. Species rankings of water use strategy were inconsistent across four metrics. A newer metric (Hydroscape) was strongly linked to various plant traits, including the leaf turgor loss (TLP), water potential at stomatal closure (Pgs90), leaf and stem hydraulic vulnerability to embolism (PL50 and Px50), safety margin of hydraulic segmentation (HSMHS), maximum stomatal conductance (gsmax) and Huber value (HV). In addition, Hydroscape was correlated with climatic variables representing the water availability at the seed source site. Along the continuum of water regulation strategy, species with narrow Hydroscapes tended to occupy mesic regions and exhibit high TLP, PL50 and Px50 values and narrow HSMHS. High gsmax recorded in species with broad hydroscapes were also associated with high HV. Despite a 4‐fold difference in Hydroscape area, all species closed their stomata prior to the onset of hydraulic dysfunction, suggesting a common stomatal response across species that minimises embolism risk during drought. Hydroscape area is useful in bridging stomatal regulation, hydraulic architecture and species drought tolerance, thus providing insight into species water use strategies.
Usage notes
Li et al. FE-2018-01132_Raw data_1
This file contains the response of percentage loss of xylem conductivity to water potential for stem and leaf, as well as stomatal conductance response to water potential during dehydration for ten species.
Li et al. FE-2018-01132_Raw data_2
This file includes predawn and midday leaf water potential for ten species during drydown.

等水-非等水调节连续体（iso/anisohydric continuum）阐释了植物如何调控叶片水势，该指标常被用于划分物种的干旱响应策略。然而，物种的干旱响应策略远不止这一连续体范畴，还涵盖了一系列气孔与水力性状。
本研究依托同质园试验，对澳大利亚东部四大主要生态系统中的10种桉树开展分析，对比了4种常用于描述干旱期间水分利用策略的指标；并探究了这些指标与植物水分利用及耐旱性相关的核心气孔、水力性状的匹配程度。
不同指标下的物种水分利用策略排序存在不一致性。
一项新兴指标——Hydroscape与多种植物性状显著相关，包括叶片膨压丧失点（TLP）、气孔关闭时的水势（Pgs90）、叶片与茎部栓塞水力脆弱性（PL50与Px50）、水力分割安全边际（HSMHS）、最大气孔导度（gsmax）以及胡伯值（HV）。
此外，Hydroscape还与反映种源地水分可获得性的气候变量显著相关。
在水分调节策略的连续谱中，Hydroscape较窄的物种多栖息于湿润生境，且表现出较高的TLP、PL50与Px50值，同时水力分割安全边际较窄；而Hydroscape较宽的物种往往具有较高的最大气孔导度，且胡伯值也偏高。
尽管不同物种的Hydroscape面积相差达4倍，但所有物种均在水力功能障碍发生前完成气孔关闭，这表明跨物种存在统一的气孔响应机制，可降低干旱期间的栓塞风险。
Hydroscape面积可有效联结气孔调控、水力结构与物种耐旱性，从而为解析物种水分利用策略提供新视角。

使用说明
Li等人 FE-2018-01132_原始数据_1
该文件包含10个物种的茎、叶木质部导水率损失百分比随水势的变化关系，以及脱水过程中气孔导度随水势的响应数据。
Li等人 FE-2018-01132_原始数据_2
该文件包含10个物种在干旱过程中的黎明前与正午叶片水势数据。