Validation of an individual-based model of forest dynamics using self-thinning relationships

Abstract

Self-thinning relationships link mean plant size and plant density for even-aged populations subjected to density-dependent mortality. Because the relationships are expressed at the population or the community level, they constitute a validation test for individual-based models of plant population dynamics. The model proposed here stems from forest gap models of the JABOWA/FORET-type and succeeds the validation test. This validates the growth and mortality individual-based local rules used in most gap models. The result arises in the model because some basic assumptions make density a negative exponential function of time and mean individual size a sigmoid function of time.