The current state of forest ecosystems in the Khosta Yew-Boxwood Grove

In this study, we aimed to assess the current state of forest ecosystems on the Black Sea coast of the Caucasus after the mass mortality of boxwoods. Soil and geobotanical studies were carried out in the Khosta Yew-Boxwood Grove, a convenient proving ground for assessment of the consequences of Cydalima perspectalis expansion. Hierarchical cluster analysis (nearest-neighbour and Euclidean distance methods), One-way ANOVA, and correlation analysis (Euclidean distance matrices for standardised data) were applied to process the soil and vegetation data. An increase in the illumination of the lower forest tiers due to the Buxus colchica destruction resulted in an intensive growth of vegetation cover and the formation of a soddy horizon in soils. These processes contributed to the accumulation of organic matter and high biological activity of the soils. The number of Buxus colchica seedlings was negatively correlated with the vegetation coverage and the number of grass and shrub species, as well as with some biological parameters of the soils. The most intensive seed regeneration of Buxus colchica was observed in forest plots with high crown density in the upper tier, undeveloped vegetation cover, and soddy soil horizon.