Data from: The coordination of dehydration tolerance and avoidance in oaks is mediated by leaf habit across a precipitation gradient
Data files
Dec 16, 2025 version files 11.46 KB
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Oak_DADT.csv
10.27 KB
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README.md
1.19 KB
Abstract
Forests worldwide are increasingly impacted by drought due to climate change, prompting plants to adapt through dehydration tolerance (DT) and avoidance (DA), two distinct physiological strategies. However, how these strategies are coordinated in response to varying precipitation remains unclear. To address this gap, we investigated key hydraulic traits associated with DT and DA in eleven oaks (Quercus spp.) across a broad precipitation gradient (498-1793 mm yr-1) in China. Specifically, we measured three DT traits: water potential at 50% loss of hydraulic conductivity (ΨP50), leaf turgor loss point water potential (ΨTLP), and wood density (WD), as well as four DA traits: water potential at stomatal closure (Ψclose), minimum leaf conductance, branch capacitance, and leaf-to-sapwood area ratio (AL:AS). When analyzed collectively, most traits showed no significant relationship with precipitation or aridity. However, distinct patterns emerged when data were analyzed by leaf habit. In evergreens, trait variation was largely and independently explained by mean annual precipitation (MAP), with stronger DT (lower ΨP50 and ΨTLP, higher WD) and enhanced DA (smaller AL:AS) under drier conditions. In contrast, deciduous species showed weaker DT (higher ΨP50) but stronger DA (higher Ψclose and lower AL:AS) as precipitation decreased, with much variance driven by interactions between MAP and mean annual temperature (MAT). Notably, DT and DA traits were strongly correlated in evergreens but weakly associated in deciduous species. Our results show that evergreen oaks rely on both DT and DA strategies for drought adaptation, whereas deciduous species primarily depend on DA mechanisms. Considering DT alone is insufficient, and incorporating multiple DA strategies is essential for a mechanistic framework to understand forest responses. We highlight the need to integrate leaf habit and complementary drought strategies into predictive models and climate-resilient forest management practices.
Dataset DOI: 10.5061/dryad.gtht76j1s
Description of the data and file structure
Files and variables
File: Oak_DADT.csv
Description: This is the hydraulic trait data derived from Liang et al. (2025, Functional Ecology).
Variables
- Site: Study sites
- Species: Tree species
- Leaf habit: Leaf habit of tree species
- Latitude: Latitude (°)
- Longitude: Longitude (°)
- DBH: Diameter at breast height (cm)
- Height: Tree height (m)
- Psi_P50: Water potential at 50% loss of xylem conductivity (MPa)
- Psi_close: Water potential at stomatal closure (MPa)
- Psi_TLP: Water potential at leaf turgor loss point (MPa)
- WD: Wood density (g cm-3)
- Cbranch: Branch capacitance (RWC MPa-1)
- gmin: Minimum leaf conductance (mmol m-2 s-1)
- Al:As: Leaf-to-sapwood area ratio (m2 cm-2)
- MAT: Mean annual temperature (°C)
- MAP: Mean annual precipitation (mm)
- AI: Aridity index (unitless)
- PET: Potential evapotranspiration (mm)
- VPD: Vapor pressure deficit (kPa)
