Abstract

Amazon rainforests face intensifying water stress due to increases in vapour pressure deficit and changing hydrological regimes. Embolism resistance (Ψ50) is a critical metric of tree survival under drought conditions, it is defined as a plant’s capacity to resist disruption of xylem water flow due to air bubble formation from water stress. However, measurements of Ψ50 are only available for a limited number of Amazon locations and species. Conversely, data on forest taxonomic composition are abundant across Amazonia, and if Ψ50 is conserved phylogenetically, these data could provide a way to scale-up drought resistance patterns. Here we evaluate Ψ50 measurements across non-flooded Amazonian tree taxa and reveal a moderate phylogenetic signal, with phylogenetic conservatism evident at the family-level. Notably, Fabaceae is amongst the most embolism-resistant tree families in Amazonia. Leveraging the phylogenetic signal we use species composition and tree size data from 448 forest plots across Amazonia to produce a macroecological assessment of Amazonian vulnerability to embolism. The resulting estimate spatial pattern reveals that forests in the Brazilian and Guiana Shield regions, where Fabaceae abundance is high, show strong resistance to embolism. In contrast, tree communities in Western Amazonia appear more vulnerable to embolism, suggesting a reduced capacity to withstand future drought conditions.

Publication Date

2026-02-26

Publication Title

Nature Communications

Volume

17

Issue

1

ISSN

2041-1723

Acceptance Date

2026-02-10

Deposit Date

2026-05-07

Funding

This paper is an outcome of J.V.T.’s doctoral thesis, which was sponsored by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES, finance code 001, GDE 99999.001293/2015-00). J.V.T. was previously supported by the NERC-funded ARBOLES project (NE/S011811/1) and is currently supported by a Birgitta Sintring Foundation (Stipend S2023-0009, Sweden) to J.V.T. and by the Swedish Research Council Vetenskapsrådet (grant no. 2019-03758 to R.M.). Data collection was largely funded by the UK Natural Environment Research Council (NERC) project TREMOR (NE/N004655/1) to D.G., E.G. and O.L.P., with further funds from CAPES - Brasil (GDE 99999.001293/2015-00) to J.V.T. and a University of Leeds Climate Research Bursary Fund to J.V.T. D.G., E.G. and O.L.P. acknowledge further support from a NERC-funded consortium award (ARBOLES, NE/S011811/1). E.G., O.L.P. and D.G. acknowledge support from NERC-funded BIORED grant (NE/N012542/1). O.P. acknowledges support from an ERC Advanced Grant and a Royal Society Wolfson Research Merit Award. R.S.O. was supported by a CNPq productivity scholarship, the São Paulo Research Foundation (FAPESP-Microsoft 11/52072-0) and the US Department of Energy, project GoAmazon (FAPESP 2013/50531-2). M.M. acknowledges support from MINECO FUN2FUN (CGL2013-46808-R) and DRESS (CGL2017-89149-C2-1-R). P.M. acknowledges support from the Royal Society Wolfson Fellowship RSWF_211008 and NERC (NE/W006308/1). E.N.H.C. was supported by NERC Knowledge Exchange Fellowship (grant ref no. NE/V018760/2). K.R. thanks the Aarhus University Research Foundation grant AUFF-E-2023-7-3 to Hanna Tuomisto. K.Y. was funded in part by the Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica (CONCYTEC) and the Programa Nacional de Investigación Científica y Estudios Avanzados (PROCIENCIA) within the framework of the E033-2023-01-BM “Alianzas Interinstitucionales para Programas de Doctorado” contest, grant number (PE501084299-2023). This paper is facilitated by the RAINFOR plot network and its long-term forest records curated at ForestPlots.net. As well as investigators and field leaders included here, we gratefully acknowledge the efforts of several hundred additional botanists, technicians and field assistants who contributed to the installation, measurement and identification of trees across South American forests. RAINFOR and ForestPlots.net have been supported by numerous people and grants since their inception. For their contributions to developing the RAINFOR network and antecedents, we are indebted to our late colleagues Elisbán Armas, Terry Erwin, Thomas Lovejoy, Alwyn Gentry, Sandra Patiño, Antonio Peña Cruz, David Neill and Jean-Pierre Veillon. For financial support we thank the European Research Council (ERC Advanced Grant 291585—‘T-FORCES’), the Gordon and Betty Moore Foundation (#1656 ‘RAINFOR’, and ‘MonANPeru’), the European Union’s Fifth, Sixth and Seventh Framework Programme (EVK2-CT-1999-00023—‘CARBONSINK-LBA’, 283080—‘GEOCARBON’, 282664—‘AMAZALERT), the Natural Environment Research Council (NE/ D005590/1—‘TROBIT’, NE/F005806/1—‘AMAZONICA’, NE/X014347/1—‘AMSINK’), several NERC Urgency and New Investigators Grants, the NERC/State of São Paulo Research Foundation (FAPESP) consortium grants ‘BIO-RED’ (NE/N012542/1), ‘ECOFOR’ (NE/K016431/1, 2012/51872-5, 2012/51509-8), ‘ARBOLES’ (NE/S011811/1, FAPESP 2018/15001-6), Brazilian National Research Council (PELD/CNPq 403710/2012-0), the Royal Society (University Research Fellowships and Global Challenges Award ICA/R1/180100 - ‘FORAMA’), the National Geographic Society (PFA-21-PP029), US National Science Foundation (DEB 1754647) and Colombia’s Colciencias. This manuscript is an output of ForestPlots.net Research Project 19, “ Hydraulic properties of Amazonian trees: spatial variation and consequences for vulnerability to drought”. ForestPlots.net is a meta-network and cyber-initiative developed at the University of Leeds to unite permanent plot records and support tropical forest scientists. We thank A. Levesley, K. Melgaço Ladvocat and G. Pickavance for ForestPlots.net management. We acknowledge the contributions of the ForestPlots.net Collaboration and Data Request Committee (B.S.M., E.N.H.C., O.L.P., T.R.B., B. Sonké, C. Ewango, J. Muledi, S.L.L., L. Qie) for facilitating this project and associated data management. Data curation, partner support, and the development of ForestPlots.net have been funded by grants including NE/B503384/1, NE/N012542/1 - ‘BIO-RED’, ERC Advanced Grant 291585 - ‘T-FORCES’, NE/F005806/1 - ‘AMAZONICA’, NE/N004655/1 - ‘TREMOR’, NE/X014347/1 - AMSINK’, NERC New Investigators Awards, the Gordon and Betty Moore Foundation (‘RAINFOR’, ‘MonANPeru’), ERC Starter Grant 758873 -‘TreeMort’, EU Framework 6, and a Leverhulme Trust Research Fellowship. Open access funding provided by Uppsala University.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Download

Share

COinS