Leaf hydraulic and photosynthetic traits mediate forest-scale resource use efficiencies across the continental United States
Temperate forests play a critical role in global carbon cycling and other ecosystem services, yet their resilience to climatic stresses remains uncertain. We combined physiology, community composition, flux data, and modeling to test a functional trait-based approach to predict forest ecosystem processes. For eight U.S. forests spanning broad precipitation and temperature gradients, we scaled up key leaf functional traits—maximum carboxylation velocity of Rubisco ( V c , m a x ), maximum leaf hydraulic conductance ( K l , m a x ), and turgor loss point (that is, wilting point, π t l p ) to predict gross primary productivity, light-use efficiency, standard and intrinsic water-use efficiency (WUE and iWUE), and their sensitivities to soil drought. In multiple regressions, ecosystem processes were strongly associated with community-weighted mean (CWM) trait values: enhanced productivity was linked with high V c , m a x ¯ , K l , m a x ¯ and π t l p ¯ , whereas high WUE and iWUE were linked with low K l , m a x ¯ and high π t l p ¯ . The CWM functional traits also influenced the sensitivity of ecosystem processes to soil moisture. A causal role of functional traits in driving ecosystem processes alongside climate was supported by parameterizing the LM4.1 vegetation model with CWM functional traits. This study highlights the important role of functional traits in determining forest responses to climate-driven water stress at a continental scale.
Authors
- Joseph Zailaa (ORCID: https://orcid.org/0000-0001-9103-190X)
- Lawren Sack (ORCID: https://orcid.org/0000-0002-7009-7202)
- Lukas J. Magee (ORCID: https://orcid.org/0000-0003-3124-2275)
- Matteo Detto (ORCID: https://orcid.org/0000-0003-0494-188X)
- Nidhi Vinod (ORCID: https://orcid.org/0000-0003-2726-4105)
- Hannes De Deurwaerder (ORCID: https://orcid.org/0000-0002-9287-2062)
- Camila D. De Medeiros (ORCID: https://orcid.org/0000-0002-5822-5603)
- Daniel J. Johnson (ORCID: https://orcid.org/0000-0002-8585-2143)
- Sergey L. Malyshev (ORCID: https://orcid.org/0000-0001-6259-1043)
- Jessica Shue (ORCID: https://orcid.org/0000-0003-3026-5838)
- Bailu Zhao (ORCID: https://orcid.org/0000-0002-1326-4801)
- Katherine C. Cushman (ORCID: https://orcid.org/0000-0002-3464-1151)
- Peter D. Blanken (ORCID: https://orcid.org/0000-0002-7405-2220)
- Sean P. Burns (ORCID: https://orcid.org/0000-0002-6258-1838)
- Marvin G. Browne (ORCID: https://orcid.org/0000-0002-9640-0759)
- Sean M. McMahon (ORCID: https://orcid.org/0000-0001-8302-6908)
- Elena Shevliakova (ORCID: https://orcid.org/0000-0003-4910-2166)
- Jeffrey D. Wood (ORCID: https://orcid.org/0000-0001-6422-2882)
- Anna T. Trugman (ORCID: https://orcid.org/0000-0002-7903-9711)
- David A. Orwig (ORCID: https://orcid.org/0000-0001-7822-3560)
- Anna Jiselle Ongjoco (ORCID: https://orcid.org/0009-0004-0815-5071)
- Christina Mckeown
- Karina Schafer
Institutions
- NSF National Center for Atmospheric Research (US)
- Louisiana State University (US)
- Oak Ridge National Laboratory (US)
- Harvard University (US)
- University of California, Santa Barbara (US)
- NOAA Geophysical Fluid Dynamics Laboratory (US)
- Université de Montpellier (FR)
- Princeton University (US)
- Universidade Federal de Pernambuco (BR)
- Department of Conservation and Recreation (US)
- Yale University (US)
- University of Florida (US)
- UMR Botanique et Modélisation de l’Architecture des Plantes et des végétations (FR)
- High Meadows Environmental Institute (US)
- Smithsonian Environmental Research Center (US)
- University of Missouri (US)
- Virginia Tech (US)
- Stanford University (US)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2026-11-09
- DOI
- https://doi.org/10.1073/pnas.2526434123
- Primary Topic
- Plant Water Relations and Carbon Dynamics
- Type
- article
- Field-Weighted Citation Impact
- 0.00