Accelerated extinction of Quercus robur L. in the park planting “Dubynka” of the National dendrological park “Sofiyivka” of the National Academy of Sciences of Ukraine

Abstract

Aim. Nowadays a sharp deterioration of the phytosanitary state of oak planting “Dubynka” has been stated in the National dendrological park “Sofiyivka”. It caused accelerated extinction of a separate area of a tree stand. Our studyaimed at making an inventory of park planting «Dubynka» to determine its condition and provide recommendations to preservation and restoration of the park structure. Methods. While carrying out inventory works, the author used methodological guidelines for conducting field works on forest inventory in the Polissya region of Ukraine (Storozhuk, 2006), methodological recommendations for inventory, taxing and monitoring of perennial plantations in historical parks of Ukraine (Kosenko et al., 2014). Categories of phytosanitary condition of trees were evaluated on the scale of N. P. Krasyns’kyy in the modification of Yu. Z. Kulahina (Tarabrin et al., 1986). Results. The degradation processes of garden-park phytocenosis had been analyzed on the example of a separate area of the planting “Dubynka “ in the National dendrological park “Sofiyivka”. In the inventory of oak planting «Dubynka » in 2016 and 2018, it was found that the number of trees with dry top had increased by 2,5 times, and dry trees by 15 times. In the park phytocenosis of oak planting “Dubynka “ a threatening dynamics of accelerated dying of trees Q. robur was noted. The presence of single 300-year-old trees of oak in artificially created park planting of the National dendrological park “Sofiyivka” testified to the possible decay of thenatural forest formation of oak, which existed before the construction of the park. Confirmation of fact of mass extinction of oak aged up to 100 years on the example of artificial plantations of the oak of the historical area “Dubynka “ in the National dendrological park “Sofiyivka” had been revealed. It was stated that the oak tree plants at the upper part of the slope of the entire “Dubynka” area was planted repeatedly on the site of oak planting since 1796. A few oak trees remained on the lower slope. Conclusions. It is recommended to create young oak plantations in the area of “Dubynka” to optimize the age structure of garden-park phytocenosis. In turn, it will disrupt the periodicity of mass extinction of one-century oak trees. This action will ensure preservation of the historic garden-park phytocenosis of oak on the “Dubynka” area and improveits aesthetic perception.