XVI International Botanical Congess

The model PHENOFIT simulates the relative variations of fitness of different tree species. This model is composed of phenological models, a frost injury model and a water stress model. Fitness is defined here as the proportion of ripe fruits an individual is able to produce each year. PHENOFIT was fitted using phenological, frost injury and water stress data for ten American species. Areas defined by a strictly positive predicted fitness according to PHENOFIT were very consistent with the distributions of the species. Compared to the few predictive models of species distribution existing, PHENOFIT is a mechanistic model which does not use the current distributions of species to be fitted. One of the most interesting applications of this model would be to predict the patterns of variation of tree species distribution under changing climate conditions.