Back to Search
Start Over
Leaves as bottlenecks: The contribution of tree leaves to hydraulic resistance within the soil-plant-atmosphere continuum.
- Source :
-
Plant, cell & environment [Plant Cell Environ] 2023 Mar; Vol. 46 (3), pp. 736-746. Date of Electronic Publication: 2023 Jan 06. - Publication Year :
- 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 (R <subscript>leaf</subscript> ) to total soil-to-leaf hydraulic resistance (R <subscript>total</subscript> ), or fR <subscript>leaf</subscript> (=R <subscript>leaf</subscript> /R <subscript>total</subscript> ), is thought to be large, but this has not been tested comprehensively. We compiled a multibiome data set of fR <subscript>leaf</subscript> using new and previously published measurements of pressure differences within trees in situ. Across 80 samples, fR <subscript>leaf</subscript> 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 fR <subscript>leaf</subscript> for 19 tree samples, which was 0.40 (95% CI = 0.29-0.56). The in situ technique produces a more accurate descriptor of fR <subscript>leaf</subscript> because it accounts for dynamic leaf hydraulic conductance. Both approaches demonstrate the outsized role of leaves in controlling tree hydrodynamics. A larger fR <subscript>leaf</subscript> may help stems from loss of hydraulic conductance. Thus, the decline in fR <subscript>leaf</subscript> with tree height would contribute to greater drought vulnerability in taller trees and potentially to their observed disproportionate drought mortality.<br /> (© 2022 John Wiley & Sons Ltd.)
Details
- Language :
- English
- ISSN :
- 1365-3040
- Volume :
- 46
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Plant, cell & environment
- Publication Type :
- Academic Journal
- Accession number :
- 36564901
- Full Text :
- https://doi.org/10.1111/pce.14524