Leaves as bottlenecks: The contribution of tree leaves to hydraulic resistance within the soil−plant−atmosphere continuum

Authors

Brett T. Wolfe, LSU Agricultural Center
Matteo Detto, Smithsonian Tropical Research Institute
Yong Jiang Zhang, University of Maine
Kristina J. Anderson-Teixeira, Smithsonian Tropical Research Institute
Tim Brodribb, University of Tasmania
Adam D. Collins, Los Alamos National Laboratory
Chloe Crawford, LSU Agricultural Center
L. Turin Dickman, Los Alamos National Laboratory
Kim S. Ely, Brookhaven National Laboratory
Jessica Francisco, LSU Agricultural Center
Preston D. Gurry, LSU Agricultural Center
Haigan Hancock, LSU Agricultural Center
Christopher T. King, LSU Agricultural Center
Adelodun R. Majekobaje, LSU Agricultural Center
Christian J. Mallett, LSU Agricultural Center
Nate G. McDowell, Pacific Northwest National Laboratory
Zachary Mendheim, LSU Agricultural Center
Sean T. Michaletz, The University of British Columbia
Daniel B. Myers, LSU Agricultural Center
Ty J. Price, LSU Agricultural Center
Alistair Rogers, Brookhaven National Laboratory
Lawren Sack, University of California, Los Angeles
Shawn P. Serbin, Brookhaven National Laboratory
Zafar Siddiq, Government College University Lahore
David Willis, LSU Agricultural Center
Jin Wu, The University of Hong Kong
Joseph Zailaa, Conservation and Research Center (National Zoo)
S. Joseph Wright, Smithsonian Tropical Research Institute

Document Type

Article

Publication Date

3-1-2023

Abstract

Within vascular plants, the partitioning of hydraulic resistance along the soil-to-leaf continuum affects transpiration and its response to environmental conditions. In trees, the fractional contribution of leaf hydraulic resistance (Rleaf) to total soil-to-leaf hydraulic resistance (Rtotal), or fRleaf (=Rleaf/Rtotal), is thought to be large, but this has not been tested comprehensively. We compiled a multibiome data set of fRleaf using new and previously published measurements of pressure differences within trees in situ. Across 80 samples, fRleaf averaged 0.51 (95% confidence interval [CI] = 0.46−0.57) and it declined with tree height. We also used the allometric relationship between field-based measurements of soil-to-leaf hydraulic conductance and laboratory-based measurements of leaf hydraulic conductance to compute the average fRleaf for 19 tree samples, which was 0.40 (95% CI = 0.29−0.56). The in situ technique produces a more accurate descriptor of fRleaf because it accounts for dynamic leaf hydraulic conductance. Both approaches demonstrate the outsized role of leaves in controlling tree hydrodynamics. A larger fRleaf may help stems from loss of hydraulic conductance. Thus, the decline in fRleaf with tree height would contribute to greater drought vulnerability in taller trees and potentially to their observed disproportionate drought mortality.

Publication Source (Journal or Book title)

Plant Cell and Environment

First Page

736

Last Page

746

Recommended Citation

Wolfe, B., Detto, M., Zhang, Y., Anderson-Teixeira, K., Brodribb, T., Collins, A., Crawford, C., Dickman, L., Ely, K., Francisco, J., Gurry, P., Hancock, H., King, C., Majekobaje, A., Mallett, C., McDowell, N., Mendheim, Z., Michaletz, S., Myers, D., Price, T., Rogers, A., Sack, L., Serbin, S., Siddiq, Z., Willis, D., Wu, J., Zailaa, J., & Wright, S. (2023). Leaves as bottlenecks: The contribution of tree leaves to hydraulic resistance within the soil−plant−atmosphere continuum. Plant Cell and Environment, 46 (3), 736-746. https://doi.org/10.1111/pce.14524