Axial Variation in Structural and Functional Traits: Advancing Our Understanding of Plant Hydraulic Plasticity

Understanding how trees respond to drought and climatic stress increasingly calls for close collaboration between experts in xylem anatomy and hydraulics. While substantial research effort has been devoted to characterizing xylem plasticity, axial variation in anatomical traits, such as conduit dimensions and pit characteristics, has often been less central in hydraulic studies, even though these gradients may influence embolism resistance and whole-path conductance. Recognizing and quantifying these structural patterns offers a valuable opportunity to strengthen physiological interpretations, enrich mechanistic models, and refine our view of acclimation and species strategies.This Research Topic seeks to encourage a productive exchange between researchers investigating xylem structure and those focused on hydraulic function. By bringing these complementary perspectives together, we aim to inspire improved methodologies, stimulate cross-disciplinary discussion, and promote a more integrated understanding of plant hydraulic behaviour.Aims of the Research Topic:• Bridge anatomical and hydraulic approaches by encouraging studies that jointly quantify axial traits and functional performance.• Promote sampling and experimental designs that explicitly account for axial trait gradients and their potential functional implications.• Clarify patterns of xylem plasticity by separating environmentally driven signals from position-related anatomical variation.• Integrate structural insights into functional models to enhance predictions of whole-plant conductance, drought responses, and carbon–water balance.• Build shared conceptual and methodological foundations that strengthen collaboration among experts in xylem anatomy, plant hydraulics, and modelling.Submissions are welcomed on topics including, but not limited to:• Axial scaling of xylem structure and function, including conduit diameter, pit traits, embolism resistance, hydraulic conductivity, and related properties.• Hydraulic function along the axis and its implications for water transport, tension gradients, embolism dynamics, and drought responses.• Sampling approaches and standardization practices that help distinguish growth-rate or position-driven effects.• Reassessing phenotypic plasticity through distance-from-apex–aware evaluations of environmental influences on xylem traits.• Ecological and evolutionary implications of axial variation, including its integration into models of species strategies, performance, and forest resilience.By cultivating dialogue among experts in xylem anatomy, hydraulics, and modelling, this collection aims to advance a more unified understanding of plant hydraulic architecture. Through interdisciplinary collaboration, we hope to refine how phenotypic plasticity is defined and measured, improve the linkage between structure and function, and ultimately enhance our capacity to forecast how forests will respond to a changing and increasingly variable climate. Topic editors: Anna Lintunen, Giai Petit Source: https://www.frontiersin.org/research-topics/77406/axial-variation-in-structural-and-functional-traits-advancing-our-understanding-of-plant-hydraulic-plasticity