Addressing controversies in the xylem embolism resistance – vessel diameter relationship

Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones.
We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P50) with hydraulically-weighted vessel diameter (Dh) and tested its link to pit membrane thickness (TPM) and specific conductivity (Ks) on species level.
Embolism-resistant species had thick pit membranes and narrow vessels. While Dh was weakly associated with TPM, the P50 – Dh relationship remained highly significant after accounting for TPM. The interspecific pattern between P50 and Dh was mirrored by a link between P50 and Ks, but there was no evidence for an intraspecific relationship.
Our ...,
This dataset is a supplement to Isasa et al. (2023) Addressing controversies in the xylem embolism resistance – vessel diameter relationship (DOI: 10.1111/nph.18731) with the raw data for the 20 temperate angiosperm tree species discussed in this manuscript. The dataset contains vulnerability curve parameters measured with the flow-centrifuge method, measurements of maximum specific conductivity obtained with a XylEm Plus device, as well as wood anatomical parameters from light microscopy (vessel diameter) and transmission electron microscopy (pit membrane characteristics). A detailed description of the measurement methods can be found in the original manuscript.
For a description of the variable names of the provided variables including context about their measurement and the corresponding units, please see the README document (“README.md”).
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The data file is provided in a .csv format and can be opened with spreadsheet software such as LibreOffice or Microsoft Excel.