Tree species richness as the element of structure and diversity in mixed stands of beech and valuable broadleaves

Abstract

In our forest science and forest operations, the tree species richness and diversity of woody species in forest stands are most often evaluated based on the total number of tree species, which is a methodologically partly inadequate approach. For this reason, the quantification and the evaluation of diversity of woody species in mixed forests of beech with valuable broadleaves in the area of the National Park „Đerdap” were analyzed by five different indices of tree species richness: number of species (S index), two indices of the species richness (R1 and R2), expected number of species in the sample with equal numbers of trees (E(S84)), and expected number of species in the sample with equal areas (E(S0,25ha)). The results showed that the level of woody species diversity in forest stands depended on the applied index characterizing the tree species richness. It was concluded that the tree species richness and diversity were the highest in the stands of ecological unit B (E(S84)=8.6 species) and in the stands of ecological unit G (E(S0,25ha)=9.4 species), and they were the lowest in the stands of ecological unit V (E(S84)=5.8 species, E(S0,25ha)=5.5 species).

Keywords

• stand structure
• tree species richness
• beech and valuable broadleaved tree species