Intensive management in European forests in the 20th century resulted in the substitution of the old-growth natural forests with plantations on vast territories. The spatial structure and tree species composition of the planted forests are simplified making the forests vulnerable to diseases and disturbances. The old-growth natural forests that remained in some places can be used as etalon forests for the reconstructed forests in similar environmental conditions. We studied spatial structure, biodiversity indicators and carbon stocks of the old-growth natural forests in the Ukrainian Carpathians in order to set forest management targets for the forest plantations in the region.

Our study presents development of a forest management model based on LP which can be easily integrated into a large-scale dynamic recursive model and contain the instruments providing future consideration for harvesting plans under recursive limitations. We introduce a general structure and simulation algorithm of the model. The forest management algorithm was tested applying historical data of Ukrainian forests. Obtained modeling results demonstrate a correct age class transition. They prove as well adequacy of utilizing benefit losses and delay costs as regulative mechanisms for temporal allocation of forest harvesting. As far as statistic data concerning age structure of Ukrainian forests are not publicly available, FesT was validated by comparing projected forest age structure with results of Global Forest Model (G4M).The comparison shows that the projections of both models are fairly close to each other. The divergence between the results can be explained by difference in forest management modelling approach.