Using long-term field data to quantify water potential regulation in response to VPD and soil moisture in a conifer tree.

ABSTRACT: The regulation of vascular water potential (Ψ_stem) by stomata is one of the most dynamic and important behaviours in vascular plants, playing a central role in determining gas exchange and vulnerability to drought. Yet, the species-specific characterization of Ψ_stem regulatory behaviour in response to soil or atmospheric dryness remains elusive. We hypothesize that Ψ_stem regulatory behaviour can only be defined when the combination of both vapour pressure deficit (VPD) and soil water potential (Ψ_soil) effects is considered. To test this hypothesis, we collected a high-resolution time series of Ψ_stem using optical dendrometers from trees of a hardy conifer, Callitris rhomboidea, monitored across multiple highly variable growing seasons.

SUBMITTER: Bourbia I 

PROVIDER: S-EPMC11982795 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature