Forest under stress: responses and recovery of water relations across scales during the compound drought in summer 2022
Year: 2026
Type: article
Abstract: The summer of 2022 was characterized by compound soil and atmospheric drought (CSAD; low soil water content, SWC, and high vapor pressure deficit, VPD) in Central Europe, threatening forest carbon sequestration and water balance, yet linked ecosystem- and tree-level hydraulic responses remain poorly resolved. We assessed the response and recovery of water relations of a beech-dominated montane mixed deciduous forest in Switzerland (CH-Lae) to the 2022 CSAD through a series of ecosystem-scale (evapotranspiration, ET; canopy conductance, Gs) as well as tree-scale measurements, including leaf-level (leaf water potential, LWP; stomatal conductance, gs), stem-level (nighttime stem rehydration, NSR) and root-level (root water uptake depth, RWU depth) variables. During peak CSAD, ET and Gs declined by up to 50%, driven primarily by low SWC. Midday and predawn LWP declined significantly. Beech and maple accessed deeper water (> 70 cm), maintaining NSR and gs during CSAD and fully recovering thereafter; spruce and fir relied on shallow water (< 30 cm), showing stronger NSR reductions but still full recovery post-CSAD. Our findings demonstrate that species-specific hydraulic traits drive forest-scale water dynamics under CSAD conditions. Integrating these insights into forest adaptation strategies will be critical for sustaining forests under intensifying compound droughts in the future.
Source: New Phytologist
DOI: 10.1111/nph.71516
Authors: Ankit Shekhar, Anna K. Gilgen, Annika Ackermann, Liliana Scapucci, Sergio Aranda‐Barranco, Anastasiia Bolshakova, Lukas Hörtnagl, Yi Wang, Franziska Richter, Fabio Turco, Ruikun Gou, Luana Krebs, Iris Feigenwinter, Roland A. Werner, Roman Zweifel, Sophia Etzold, Marius Floriancic, Stefan Osterwalder, Mana Gharun, Nina Buchmann
Institutions: Indian Institute of Technology Kharagpur, ETH Zurich, Institute of Agricultural Sciences, Universidad de Granada, York University, Lund University, Swiss Federal Institute for Forest, Snow and Landscape Research, Northwest A&F University, Stanford University, University of Zurich, University of Münster
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Life on land
Open Access status: hybrid
Estimated APC paid: $5,790
Awards: Unravel the changing contributions of abiotic vs. biotic drivers of ecosystem gas exchange under weather extremes, G1356565639, G1540691148, G1603607104, Assessment of formal, natural and social insurances: how to cope best with impacts of extreme events on grasslands for sustainable farming systems?, G7590065177, ICOS-CH Phase 3, COS and below-canopy CO2 fluxes of two Swiss forests: understanding land-atmosphere ecosystem exchange (COCO)
OpenAlex ID: W7208836332