Abstract
The relevance of the study is determined by the need to preserve natural values, which are considered the heritage of all mankind, namely the primaeval forests and old-growth beech forests of the UNESCO World Natural Heritage. The aim of the research was to study the state and structure of the beech primaeval forest in the national nature park “Zacharovanyi Krai”. For the study, a permanent sample plot of 1 ha (100×100 m) was laid down in the prevailing forest type – moist pure beech forest. This plot is located in the optimal forest-growing conditions for European beech (Fagus sylvatica L.) within the Vyhorlat-Hutyn volcanic ridge of the Ukrainian Carpathians. It was found that the beech forest stand on the plot is pure in composition and complex in form, characterised by different development phases (age groups by diameter): the first layer stand belongs to the mature age group (senile), the second layer – to the middle-aged group, and the third – to the pole (virginal). It was determined that 95% of the primaeval forest stock is the stock of the first layer, while the share of commercial trees of the first layer is 89% (66% of the total volume of stem wood of trees on the permanent sample plot). The main types of damage in the site are caused by abiotic factors. As a result of such damage, 43 m3‧ha-1 of deadwood was recorded, characterised by all 5 stages of decomposition. Under the canopy of the stand, 10,375 pcs‧ha-1 of undergrowth was recorded, of which the share of beech is 88%. Beech undergrowth is weakly differentiated by age groups: it was recorded only in the group of 7-year-olds and older and well-differentiated by height groups. By age group, undergrowth belongs to the juvenile-immature age state. The herbaceous cover is typical for nemoral forests. The presence of stationary research plots in the National Nature Park “Zakharovanyy Kray” makes it possible to constantly monitor the trends of natural development of the ecosystem – the beech primaeval forest