Characteristics of spread and restoration of Pinus cembra L. in the Chornohora massif of the Ukrainian Carpathians

Abstract

During the previous century, natural stands of Pinus cembra suffered significant losses due to the unreasoned methods of forestry, animal husbandry, cultural traditions of the local population, and the way of land possession in the Carpathian region in the past socio-political realities. The largest losses have occurred in the smallest habitats of P. cembra in the Chornohora massif. The case study in this part of the Carpathians involved changes of demographic parameters of Swiss stone pine population due to restoration succession processes in its habitats. Possible effects of climate change are also considered. Current trends in the population dynamics of Swiss stone pine indicate certain positive changes that have taken place over the past few decades, mainly after the introduction of some environmental regulations. Grazing pressure reduction in the highlands of the Carpathians should also be considered positive. At the same time, its complete cessation may have negative consequences for the restoration of the Swiss stone pine habitats within its former historical boundary. Necessary condition for recolonization of the lost territories by P. cembra is the presence of free niches at the upper forest or subalpine zones, where its ecological and biological advantages over spruce are fully realized. Another important factor is the optimal ratio between the number of Nucifraga caryocatactes and the number of fruit-bearing trees in the "mother" population. The most active recovery of P. cembra occurred at the beginning of the restoration succession in shrubby and herbaceous patches. At present, the intensive spread of Picea abies and Pinus mugo is an obstacle to the expansion of its population range. The impact of climate change on the restoration of Swiss stone pine is not obvious, as prolongation of the growing season enhances competition with other tree species while the timberline raises higher hypsometric levels.