White fir (Abies alba) is one of the most productive and ecologically most valuable native European woody plants. In the forestry of the old continent, therefore, great attention is paid to it not only for its forestry value, but also for its repeated death. Experts from the Faculty of Forestry and Wood Sciences at the CULS also contributed to a better understanding of the growth of this tree species.
The study took place in a forest zone extending from the Western Carpathians through central Slovakia to the Low Beskydy Mountains near the border with Ukraine and focused on the period after the culmination of air pollution in Czechoslovakia. The aim was to answer whether the reduction of atmospheric SO2 and NOx concentrations is the main factor for the renewal of growth. Part of the research was to monitor the relationship between climate and growth, as the second variable that may have contributed to accelerated growth.
Tree growth is generally affected not only by nutrients sufficiency, but also by the chemical composition of the air. Polluted air can have both direct and indirect effects. It causes damage to vegetative tissue, alters physiological pathways in tissues or indirectly manifests itself through acidification of the soil and the subsequent release of aluminium and heavy metal ions, thereby blocking the activity of enzymes and thus suppressing plant growth. For trees, these changes are very well known in the growth of annual rings, which scientists measured on 20 dominant trees of four different regions of the Western Carpathians.
Some authors suggest that recent climate change is the most important factor causing increased species growth, while others have suggested that rapid emission reductions over the past 30 years have made a significant contribution to regenerating fir and spruce growth. The results of this study point to a common impact and a combination of both factors. Behind the renewed faster growth of fir in Slovakia is not only a rapid decrease in atmospheric SO2 and nitrogen oxides, but also a significant increase in average temperatures in April, June, July and November.
The results of this research are clear evidence of how humans can easily influence the growth of plants and trees. Therefore, we and our descendants have no choice but to work in our own interest to improve the environment not only for people but also for other organisms.
Ing. Michal Bošeľa, Ph.D.
Ing. Michal Bošeľa, Ph.D., (* 1981) graduated from the Technical University in Zvolen. He received his doctorate in forestry typology in 2011 from the same university. He currently works at the National Forestry Center as a researcher and also works at the Faculty of Forestry and Wood Sciences at the CULS in Prague as a teacher and researcher.
Prepared by: Kateřina Swólová