Leaf conductance decreased under free-air CO<sub>2</sub> enrichment (FACE) for three perennials in the Nevada desert

New Phytologist

By: Robert S. Nowak, Lesley A. Defalco, Carolyn S. Wilcox, Dean N. Jordan, James S. Coleman, Jeffrey R. Seemann, and Stanley D. Smith

A common response of plants to elevated atmospheric CO₂ concentration (CO₂) is decreased leaf conductance. Consequently, leaf temperature is predicted to increase under elevated CO₂.
Diurnal patterns of leaf conductance and temperature were measured for three desert perennials, the C₃ shrub Larrea tridentata, C₃ tussock grass Achnatherum hymenoides and C₄tussock grass Pleuraphis rigida, at the Nevada Desert FACE facility. Measurements were made on ambient and c. 550 µmol mol⁻¹ CO₂ plots through both a wet and dry year.
Reductions in conductance were 35%, 20% and 13% for Pleuraphis, Achnatherum and Larrea, respectively. Decreased conductance occurred throughout the day only for Pleuraphis. Both C₃species had smaller CO₂ effects during dry periods than wet. Leaf temperature did not differ significantly between elevated and ambient CO₂ for any species. Comparisons of blower-control and nonring plots indicated that the FACE apparatus did not confound our results.
All three species exhibited decreased leaf conductance under elevated CO₂, although reductions were not uniform during the day or among years. Nonetheless, leaf energy balance was only minimally changed for these microphyllous desert perennials.

Additional publication details
Publication type	Article
Publication Subtype	Journal Article
Title	Leaf conductance decreased under free-air CO₂ enrichment (FACE) for three perennials in the Nevada desert
Series title	New Phytologist
DOI	10.1046/j.1469-8137.2001.00102.x
Volume	150
Issue	2
Year Published	2001
Language	English
Publisher	Wiley
Contributing office(s)	Western Ecological Research Center
Description	10 p.
First page	449
Last page	458
Google Analytic Metrics	Metrics page