A change in structural diversity and regeneration processes of the spruce virgin forest in Nefcerka NNR (TANAP) in relation to altitude

This report assesses the structural diversity of the spruce virgin forest in Nefcerka NNR in the Tatra National Park (TANAP). The structure of the virgin forest is evaluated by the indices proposed by Clark & Evans, Fuldner and Jaehne & Dohrenbusch. Concerning the spatial distribution of trees (Clark & Evans index), a statistically significant difference was confirmed between the growth stage and the optimum and the breakdown stages. The influence of altitude on the tendency of concentration of virgin forest trees was also confirmed. In the case of complex diversity evaluation by the Jaehne & Do- hrenbusch index (1997), a statistically significantly different diversity of the spruce virgin forest between the growth stage and the other stages was found. The analysis of the regeneration processes revealed their good dynamics even at an altitude above 1,400 m, and with the ascending altitude (above 1,300 m) the dead wood and knolls of wind-thrown roots have the greater importance as seedbeds.