Anamorphic site index curves for Moesian beech ( fagus x taurica popl.) In the region of Zagubica, eastern Serbia

Abstract

Data on average age and height of dominant moesian beech trees from 109 temporary sample plots were used to establish anamorphic site index curves (SI) calculated from seven growth functions (Chapman-Richards, Korf, Korsun, Hosfeld IV, Todorovic, Schumacher and Prodan). The base age for calculation of SI was 100 (SI100)). The guide curve method was applied. For the evaluation of the models, statistical as well as visual examinations were considered. The results showed that all the applied models had a relatively high coefficient of determination (R-2) value, indicating that the models accounted for more than 65% of the variation in the dominant height, which can be considered as large effects. Korsun's function shows the best overall statistics, which makes this model the most suitable for the construction of anamorphic site index curves for the study area. The obtained results are of importance for effective decision making in forest management planning, forest policy, and ecology in Serbia. Namely, regarding the relatively large sample and well-distributed sample units per age and site classes as well as the source of data (temporary sample plots), the developed site index curves and the method of stratifying the sites according to their productivity were performed for the first time in Serbia. Future studies should be performed in order to expand the knowledge on the dominant beech height-age relationships in the studied region using another well-known procedure of site index construction - polymorphic site index curves and stem analysis data.