Details

Autor(en) / Beteiligte

• Duvert, Clément
• Barbeta, Adrià
• Hutley, Lindsay B.
• Rodriguez, Leidy
• Irvine, Dylan J.
• Taylor, Andrew R.

Titel

Cavitron extraction of xylem water suggests cryogenic extraction biases vary across species but are independent of tree water stress

Ist Teil von

• Hydrological processes, 2024-02, Vol.38 (2), p.n/a

Ort / Verlag

Hoboken, USA: John Wiley & Sons, Inc

Erscheinungsjahr

2024

Link zum Volltext

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Cryogenic vacuum distillation (CVD) is a widely used technique for extracting plant water from stems for isotopic analysis, but concerns about potential isotopic biases have emerged. Here, we leverage the Cavitron centrifugation technique to extract xylem water and compare its isotopic signature to that of CVD‐extracted bulk stem water as well as source water. Conducted under field conditions in tropical northern Australia, our study spans seven tree species naturally experiencing a range of water stress levels. Our findings reveal a significant deuterium bias in CVD‐extracted bulk stem water when compared to xylem water (median bias −14.9‰), whereas xylem water closely aligned with source water (median offset −1.9‰). We find substantial variations in deuterium bias among the seven tree species (bias ranging from −19.3‰ to −9.1‰), but intriguingly, CVD‐induced biases were unrelated to environmental factors such as relative stem water content and predawn leaf water potential. These results imply that inter‐specific differences may be driven by anatomical traits rather than tree hydraulic functioning. Additionally, our data highlight the potential to use a site‐specific deuterium offset, based on the isotopic signature of local source water, for correcting CVD‐induced biases. This paper addresses the drivers of the deuterium bias associated with cryogenic vacuum distillation (CVD) of stem water. Using the Cavitron centrifugation technique to extract xylem water and compare its isotopic signature to that of CVD‐extracted bulk stem water, we find substantial variations in deuterium bias among seven tree species under field conditions. Interestingly, the deuterium bias exhibits no correlation with environmental factors such as relative stem water content and drought stress (as estimated by pre‐dawn leaf water potentials).