Abstract
Oikawa model (1985) was improved to simulate annual variations of dry-matter productions of forests. Spatial information such as tree density and canopy closure were included into the model, and the validity of this model were discussed. In terms of qualitative aspects, several kinds of experimental laws of forest growth such as (1) overshooting of leaf biomass during the process of canopy closure, (2) dependence of overshooting periods on tree density, (3) constant final yield, and (4) linear relationship between leaf life-span and leaf biomass, were well simulated. In quantitative view points, simulation results were also compared with the field observation data by Hachiya et al. (1989) for high density stands of Pinus Densiflora. Annual changes of biomass and primary production rate were simulated well, but litterfall rate was not.
