A test of the optimality approach to modelling canopy properties and CO₂ uptake by natural vegetation

STANISLAUS J. SCHYMANSKI, MICHAEL L. RODERICK, MURUGESU SIVAPALAN, LINDSAY B. HUTLEY & JASON BERINGER

Plant, Cell and Environment (2007) 30, 1586–1598 doi: 10.1111/j.1365-3040.2007.01728.x

Abstract

Photosynthesis provides plants with their main building material, carbohydrates, and with the energy necessary to thrive and prosper in their environment.We expect, therefore, that natural vegetation would evolve optimally to maximize its net carbon profit (NCP), the difference between carbon acquired by photosynthesis and carbon spent on maintenance of the organs involved in its uptake. We modelled NCP for an optimal vegetation for a site in the wet-dry tropics of northAustralia based on this hypothesis and on an ecophysiological gas exchange and photosynthesis model, and compared the modelled CO₂ fluxes and canopy properties with observations from the site. The comparison gives insights into theoretical and real controls on gas exchange and canopy structure, and supports the optimality approach for the modelling of gas exchange of natural vegetation. The main advantage of the optimality approach we adopt is that no assumptions about the particular vegetation of a site are required, making it a very powerful tool for predicting vegetation response to long-term climate or land use change.

Original Publication

Please download from http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-3040.2007.01728.x or send an email to sschym at bgc-jena.mpg.de.

Corrections

Equation (1) in the paper is missing a minus sign. The correct equation should be: J=Jmax*(1-e^(-alpha*Il/Jmax))

Data and Model Code

The data used for the model run was measured as part of the Fluxnet Project and is subject to the Fluxnet data use policy that can be found under http://www.fluxnet.ornl.gov/fluxnet/datapolicy.cfm or http://www.fluxdata.org/DataInfo/default.aspx. Please contact the principal investigator of the Howard Springs site (Dr. Jason Beringer) if you wish to use the data. The contact details and more information about the data and the site can be found under http://www.arts.monash.edu.au/ges/research/climate/fire/index.php.

For the purpose of reproducing the results presented in the associated publication, you can find the data used in the below table. The code used to convert the data and generate the results is given, too. Please note that the code contains additional computations and plots not addressed in the publications. Neither I nor anyone else guarantees the correctness of any of the data offered for download on this site. However, should you encounter problems or have questions, feel free to send an email to sschym at bgc-jena.mpg.de.

You need the software Mathematica by Wolfram or Mathematica Player to view and evaluate the code. Mathematica Player can be downloaded for free from http://www.wolfram.com/products/player.