Effects of competition mode on the spatial pattern dynamics of wave regeneration in subalpine tree stands

The effects of competition between individuals (the degree of competitive a symmetry and the intensity of competition; an endogenous biological factor) and the intensity of disturbance (unidirectional prevailing winds in the p resent paper; an exogenous environmental factor) on the spatial pattern dyn amics of wave regeneration in subalpine regions were studied by using a cou pled map lattice model (a lattice model with discrete time, discrete space and continuous state) of plant populations. It was shown by simulation that the wave-shaped spatial pattern of regeneration is more likely to emerge u nder symmetric competition than under asymmetric competition and that the l ikelihood of emergence increases with the intensity of disturbance, It was already shown both theoretically and by held data analysis that Abies under goes symmetric competition and that Betula undergoes asymmetric competition . Therefore, a theoretical explanation can be given as to why the wave-shap ed spatial pattern occurs in Abies forests but not in Betula forests althou gh both the species occur in subalpine regions. Our theoretical study showe d that the interaction between endogenous and exogenous factors determine t he spatial pattern dynamics in relation to the regeneration of plant commun ities. (C) 1999 Elsevier Science B.V. All rights reserved.