Harwood, Richard, Cernusak, Lucas A., Drake, John E., Barton, Craig V.M., Tjoelker, Mark G., and Barbour, Margaret M. (2024) Isotopic steady state or non-steady state transpiration? Insights from whole-tree chambers. Tree Physiology, 44 (11). tpae125.

Preview

PDF (Published Version) - Published Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (1MB) | Preview

Abstract

Unravelling the complexities of transpiration can be assisted by understanding the oxygen isotope composition of transpired water vapour (δE). It is often assumed that δE is at steady state, thereby mirroring the oxygen isotope composition of source water (δsource), but this assumption has never been tested at the whole-tree scale. This study utilized the unique infrastructure of 12 whole-tree chambers enclosing Eucalyptus parramattensis E.C.Hall trees to measure δE along with concurrent temperature and gas exchange data. Six chambers tracked ambient air temperature and six were exposed to an ambient +3 °C warming treatment. Day time means for δE were within 1.2‰ of δsource (−3.3‰) but varied considerably throughout the day. Our observations show that E. parramattensis trees are seldom transpiring at isotopic steady state over a diel period, but transpiration approaches source water isotopic composition over longer time periods.

Item ID:	85268
Item Type:	Article (Research - C1)
ISSN:	1758-4469
Copyright Information:	© The Author(s) 2024.
Funders:	Australian ResearchCouncil (ARC)
Projects and Grants:	ARC DP170104267, ARC DP140103415
Date Deposited:	29 Apr 2025 03:10
FoR Codes:	31 BIOLOGICAL SCIENCES > 3108 Plant biology > 310806 Plant physiology @ 100%
SEO Codes:	28 EXPANDING KNOWLEDGE > 2801 Expanding knowledge > 280102 Expanding knowledge in the biological sciences @ 100%
Downloads:	Total: 1 Last 12 Months: 1
	More Statistics