SIZE-STRUCTURE-BASED MODELS OF FOREST DYNAMICS TO INTERPRET POPULATION-LEVEL AND COMMUNITY-LEVEL MECHANISMS

Functional size-structure-based models of forest tree population dynamics present a unifying explanation for population-level patterns and tree community organization. Density-dependent regulation can be explicitly replaced by the effect of size-structure-dependent suppression on demographic processes in functional size-structure models. This suppression effect sufficiently explains various patterns reported for crowded even-aged populations. Further, it stabilizes natural forest populations of overlapping generations at a stationary state with balanced recruitment and mortality. The spatial heterogeneity of light resources created by tree size structure offers an opportunity for multiple species to coexist by means of trade-offs between demographic parameters. The energy correlation of tree species diversity at a geographic scale is also attributable to the architectural feature of forests.