Structure and dynamics of selected stands of primeval character in the Pieniny National Park

The purpose of this study was to determine changes which occurred during 23 years (1974–1997) in four stands in respect of species composition, structure, developmental stages and phases. In 1997 the Walusiowka stand represented the growing up stage, phase of a multistory structure, and during the study period its volume decreased from 698 to 676 m3/ha.The Przełęcz Sosnow stand was in the growing up stage, phase of a little diversified storied structure and regeneration, and its volume decreased from 696 to 622 m3/ha.The Grodek stand during the entire study period was in the growing up stage, phase of the selection forest structure and regeneration, and its volume increased from 529 to 585 m3/ha.The Facimiech stand in 1997 was in the optimum stage, phase of aging and regeneration, and its volume decreased from 688 to 661 m3/ha.During 1974–1997 the percentage of fir (Abies alba) considerably decreased in three stands (Walusiowka from 46 to 33%, Przełęcz Sosnow from 58 to 36%, Grodek from 42 to 24%).The Facimiech stand was almost a pure fir stand during the entire control period. In the Przełęcz Sosnow stand, due to a rapid mortality of fir and presence of vital trees of beech (Fagus sylvatica) of the growing up and optimum growth generations, the break up stage did not take place but the growing up stage had developed, which indicated the disturbance of the natural cycle of the primeval forest described by Korpel’. A scarce presence of fir upgrowth and prevalence of beech in stands composed of these two species permits to suppose that fir will be retreating in favor of beech.