Marcus C. Ferraz, Gustavo M. Souza and Carmen P. C. Prado

Many studies in the last years showed that, for a wide variety of plants, stomata apertures exhibits spatial temporal patterns in a phenomena known as patchy stomatal conductance. Many attempts were made to build numerical models to explain this complex behavior, but none were able to explain all of behaviors observed in nature. In this work we discuss some limitations of an hydraulic cellular automaton model proposed by Haefner, Buckley & Mott in 1997 (PC&E,20,1997). Besides considering a more realistic geometry, in which the areola are not hydraulically isolated, as in the original model, we show that small changes in the dynamics of individual stomata can lead to patchy behavior.

Mathematical modeling, non-linear dynamics, patchy stomatal conductance, plant gas exchange, hysteresis.

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