Document Type
Article
Publication Date
6-12-2026
Department
College of Forest Resources and Environmental Science
Abstract
The magnitude of the terrestrial carbon sink remains a key uncertainty in future climate projections, in part due to poorly understood links between carbon uptake and its allocation to woody biomass in vegetation. Here, in this study, we show that photosynthesis and aboveground growth occur asynchronously across diel to seasonal scales in eight North American oak species. Across 137 tree ring sites, current-year annual growth was insensitive to climate variability after midsummer despite 26 to 36% of annual gross primary productivity (GPP) occurring during this period. Hourly GPP flux and growth measurements at four sites spanning seven site years further demonstrate that wood formation ceases earlier than photosynthesis and is restricted to periods of low atmospheric aridity and temperature. This photosynthesis-growth decoupling intensifies with interannual variability in vapor pressure deficit (r = 0.86, P < 0.05), suggesting that by assuming tight coupling between photosynthesis and woody biomass, current earth system models may overestimate long-term carbon sequestration in forests.
Publication Title
Science Advances
Recommended Citation
Rao, M.,
Pacheco-Solana, A.,
Li, R.,
Oryan, B.,
Jensen, J.,
Rodriguez-Caton, M.,
Voelker, S.,
&
et al.
(2026).
Decoupled carbon assimilation and growth responses to aridity in temperate deciduous oaks.
Science Advances,
12(24).
http://doi.org/10.1126/sciadv.ady7139
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p2/2739
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Version
Publisher's PDF
Publisher's Statement
Copyright © 2026 the Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Publisher’s version of record: https://doi.org/10.1126/sciadv.ady7139