© 1986 Heron Publishing—Victoria, Canada
Optimal control of gas exchange
Pertti Hari (1), Annikki Mäkelä (2), Eeva Korpilahti (1) and Maria Holmberg (1)
1. Department of Silviculture, University of Helsinki, Unioninkatu 40 B, 00170 Helsinki, Finland / 2. IIASA, A-2361 Laxenburg, Austria /
Summary
A major difficulty in evaluating the optimization theory of leaf gas exchange under conditions of water deficit has been that
of obtaining suitable experimental data. Mathematical solutions to three formulations of optimal stomatal control are presented
which can be tested experimentally. First, it is assumed that the movement of stomata and changes in environmental factors
are slow compared to changes in the internal CO2 concentration. The optimization problem is solved under this assumption, and the procedures for testing the solution experimentally
are described. Second, instantaneous stomatal response is postulated and the solution suggests that very rapid oscillations
provide optimal CO2 uptake. Third, variable stomatal dynamics are postulated and the mathematical solution shown to be similar to that of the
second case. The second and third cases can also be tested empirically.
