Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • S. S. Paligi - , University of Würzburg (Author)
  • R. M. Link - , Chair of Forest Botany, University of Würzburg (Author)
  • E. Isasa - , University of Würzburg (Author)
  • P. Bittencourt - , University of Exeter (Author)
  • J. S. Cabral - , University of Würzburg, University of Birmingham (Author)
  • S. Jansen - , Ulm University (Author)
  • R. S. Oliveira - , State University of Campinas (Author)
  • L. Pereira - , Ulm University (Author)
  • B. Schuldt - , Chair of Forest Botany, University of Würzburg (Author)

Abstract

The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.

Details

Original languageEnglish
Pages (from-to)1171-1185
Number of pages15
JournalPlant biology
Volume25
Issue number7
Publication statusPublished - Dec 2023
Peer-reviewedYes

External IDs

PubMed 37703535
ORCID /0000-0003-0588-3757/work/170587658

Keywords

Keywords

  • Drought tolerance traits, flow-centrifuge, method comparison, plant pneumatics, Pneumatron, transport, vulnerability curve, xylem embolism resistance