Collective growth patterns reveal the high growing potential of older silver fir trees in a primeval forest in Romania’s Southern Carpathians


  • Sergiu A. HORODNIC University “Ştefan cel Mare”of Suceava, Faculty of Forestry, 13 Universităţii, 720229, Suceava (RO)
  • Cătălin C. ROIBU University “Ştefan cel Mare”of Suceava, Faculty of Forestry, 13 Universităţii, 720229, Suceava (RO)



basal area increment; collective growth patterns; ecological modelling; intraspecific facilitation; old-growth forest


The trees’ ability to respond and adjust to very different growing conditions during their lifespans varies depending on tree species and the site-specific situations. Identifying the underlying mechanisms and the individual drivers that may affect the patterns of tree growth is crucial in ecological and economic terms. How long can forest trees grow and sustain biomass accumulation, with increasing age, is still under debate. In order to determine the factors that influence growth releases for silver fir (Abies alba Mill.) trees in a temperate old-growth forest of Romania's Southern Carpathians, an analysis of radial and basal area growth patterns was initiated. Dendroecological methods were used to reconstruct radial growth both at the individual level, but especially at the group level, in four clusters obtained by a prior k-cluster analysis depending on social status. The study results showed that the growth rate of older trees increases continuously for this species at stand level, even after the typical harvesting age in managed forests. Although the direction and intensity of the climate-growth correlations at individual level were very different, the considered climatic variables explaining little to none of the growth variation, the cumulative response of the analysed trees to climate change is directly correlated with the mean July-August temperature, confirming the capacity of the silver fir to tolerate drought. Our results demonstrate that the trees of the same species are able to obtain together a temporal plasticity in strategies, exceeding the adaptability of individuals considered separately and suggest the positive impact of facilitative intraspecific interactions on forest growth.


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How to Cite

HORODNIC, S. A., & ROIBU, C. C. (2020). Collective growth patterns reveal the high growing potential of older silver fir trees in a primeval forest in Romania’s Southern Carpathians. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 48(2), 1085–1099.



Research Articles
DOI: 10.15835/nbha48211949