Tag: Cernusak L. A.

An optimal stomatal model

 

Optimal stomatal behaviour around the world

by Lin Y.-S., Medlyn B. E., Duursma R. A., Prentice I. C., Wang H., Baig S., Eamus D., Resco de Dios V., Mitchell P., Ellsworth D. S., Op de Beeck M., Wallin G., Uddling J., Tarvainen L., Linderson M.-L., Cernusak L. A., Nippert J. B., Ocheltree T. O., Tissue D. T., Martin-StPaul N. K., Rogers A., Warren J. M., De Angelis P., Hikosaka K., Han Q. et al. (2015)

in Nature Climate Change5,459–464(2015)doi:10.1038/nclimate2550

http://www.nature.com/nclimate/journal/v5/n5/full/nclimate2550.html?WT.ec_id=NCLIMATE-201505

nclimate2550-f1
Figure 1: Climatic space covered by the Stomatal Behaviour Synthesis Database, shown as mean temperature during the period with daily mean temperatures above 0 °C and moisture index. – Coloured circles represent climatic space for the database, with different colours indicating different plant functional types. Grey hexagons represent global climatic space for which vegetation is present. – http://www.nature.com/nclimate/journal/v5/n5/carousel/nclimate2550-f1.jpg

Abstract

Stomatal conductance (gs) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of gs in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of gs that allow predictions of stomatal behaviour are lacking.

Here, we present a database of globally distributed gs obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model1 and the leaf and wood economics spectrum2, 3.

We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of gs across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.