Simulation of heathland vegetation dynamics

A computer model, used to simulate changes in heathland composition after fire, is based on simple stochastic representations of establishment, growth, mortality and competition for space. Model parameters - establishment rates, maximum diameters and heights and growth constants - were estimated for Calluna vulgaris, Empetrum nigrum and Erica tetralix on a heathland in the Netherlands where these 3 species are co-dominant. Experiments revealed differences in the strategies of the species, compensatory and synergistic effects, and an instance of competitive mutualism - illustrating the complex community behaviour that can emerge from a relatively simple model. The mature community is not at an uneven-aged equilibrium; natural disturbances, climatic variation and rational management may prevent this. -from Authors