Estimation of forest-stand net primary productivity using fraction phytomass distribution model

Methods for assessing the primary productivity of the forest stands between various tree species in different environmental conditions are considered. Methods for the primary productivity assessment using data on the phytomass fractions and stand wood stock have been proposed. It is shown that the Zipf-Pareto equation of the relationship between the phytomass of some tree fractions in the stand can be used for a primary productivity estimation of the stock volume. A model analogous to R. Solow’s macroeconomic model has been proposed to describe the processes of the phytomass growth in the forest stand.