Leaf Stomatal Traits of Trees in Relation to Gas Exchange

 

Variation in Leaf Stomatal Traits of 28 Tree Species in Relation to Gas Exchange along an Edaphic Gradient in a Bornean Rain Forest.

by Russo S.E., Cannon W. L., Elowsky C., Tan S., Davies, S. J. (2010)

  1. Sabrina E. Russo2,3,6,
  2. Whitney Logan Cannon2,
  3. Christian Elowsky4,
  4. Sylvester Tan3,5 and
  5. Stuart J. Davies3

Author Affiliations


  1. 2School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588 USA

  2. 3Center for Tropical Forest Science–Arnold Arboretum Asia Program, Harvard University, Cambridge, Massachusetts 02138 USA

  3. 4Center of Biotechnology, University of Nebraska, Lincoln, Nebraska 68588 USA

  4. 5Forest Research Centre, Sarawak Forestry Corporation, Kuching, Sarawak, Malaysia

in American Journal of Botany, 97, 1109-1120. –

http://dx.doi.org/10.3732/ajb.0900344 – 

CrossRefPubMed – 

http://www.amjbot.org/content/97/7/1109

ABSTRACT

Premise of the study: Quantifying variation in functional traits associated with shifts in the species composition of plant communities along resource gradients helps identify environmental attributes important for community assembly. Stomates regulate the balance between carbon assimilation and water status in plants. If environmental attributes affecting photosynthetic water-use efficiency govern species distribution along an edaphic gradient, then adaptive variation in stomatal traits of plant species specializing on different soils should reflect belowground resource availability.

Methods: We tested this hypothesis by quantifying stomatal trait variation in understory saplings of 28 Bornean tree species in relation to gas exchange and water-use efficiency (WUE).

Key results: Comparisons between congeneric specialists of the more fertile, moister clay and the less fertile, well-drained sandy loam revealed little evidence of similar shifts in stomatal traits across genera, nor was stomatal pore index correlated with gmax, Amax, or WUE (Amax/gmax or Δ13C), suggesting that stomates may be overbuilt in these shaded juveniles. Amax was higher on sandy loam, likely due to higher understory irradiance there, but there were no other significant differences in gas exchange or WUE.

Conclusions: Despite substantial diversity in stomatal anatomy, there were few strong relationships between stomatal, photosynthetic, and WUE traits in relation to soil resources. Routine differences in water availability therefore may not exert a dominant control on the distributions of these Bornean tree species. Furthermore, the clades represented by these 12 genera may possess alternative functional designs enabling photosynthetic WUE that is sufficient to these humid, understory environments, due to whole plant-functional integration of stomatal traits with other, unmeasured traits influencing gas exchange.

 

Advertisements

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s