Do 2H and 18O in leaf water reflect environmental drivers differently?

Lucas A. Cernusak*, Adrià Barbeta, Rosemary T. Bush, Rebekka Eichstaedt, Juan Pedro Ferrio, Lawrence B. Flanagan, Arthur Gessler, Paula Martín-Gómez, Regina T. Hirl, Ansgar Kahmen, Claudia Keitel, Chun Ta Lai, Niels C. Munksgaard, Daniel B. Nelson, Jérôme Ogée, John S. Roden, Hans Schnyder, Steven L. Voelker, Lixin Wang, Hilary Stuart-WilliamsLisa Wingate, Wusheng Yu, Liangju Zhao, Matthias Cuntz

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

We compiled hydrogen and oxygen stable isotope compositions (δ2H and δ18O) of leaf water from multiple biomes to examine variations with environmental drivers. Leaf water δ2H was more closely correlated with δ2H of xylem water or atmospheric vapour, whereas leaf water δ18O was more closely correlated with air relative humidity. This resulted from the larger proportional range for δ2H of meteoric waters relative to the extent of leaf water evaporative enrichment compared with δ18O. We next expressed leaf water as isotopic enrichment above xylem water (Δ2H and Δ18O) to remove the impact of xylem water isotopic variation. For Δ2H, leaf water still correlated with atmospheric vapour, whereas Δ18O showed no such correlation. This was explained by covariance between air relative humidity and the Δ18O of atmospheric vapour. This is consistent with a previously observed diurnal correlation between air relative humidity and the deuterium excess of atmospheric vapour across a range of ecosystems. We conclude that 2H and 18O in leaf water do indeed reflect the balance of environmental drivers differently; our results have implications for understanding isotopic effects associated with water cycling in terrestrial ecosystems and for inferring environmental change from isotopic biomarkers that act as proxies for leaf water.

Original languageEnglish (US)
Pages (from-to)41-51
Number of pages11
JournalNew Phytologist
Volume235
Issue number1
DOIs
StatePublished - Jul 2022

Keywords

  • evaporative enrichment
  • isotopic biomarker
  • leaf water
  • relative humidity
  • stable isotopes

ASJC Scopus subject areas

  • Physiology
  • Plant Science

Fingerprint

Dive into the research topics of 'Do 2H and 18O in leaf water reflect environmental drivers differently?'. Together they form a unique fingerprint.

Cite this