Tree Species Biodiversity in Small Ukrainian Towns

Biodiversity is one of the important indicators of ecosystem sustainability, which is less studied in relation to urban areas, particularly Ukraine, and even more so in small towns. Taking the example of three small Ukrainian towns, the biodiversity of tree species is compared in the article. The studied small towns are located in two geographic zones, mixed forests (Polissya) and forest-steppe, and administratively, in Chernihiv and Kyiv regions. An inventory of trees in the residential area of Ukrainka, in the central streets of Novhorod-Siverskyi, as well as in the central part and all streets of Vyshhorod was conducted. Thus, the species richness of trees both between the studied towns and between its central part and the whole territory of the town was compared. The species structure of tree plantings in terms of richness, diversity, dominance, alignment, and similarity was assessed. The obtained results were subjected to cluster and correlation analysis. It was found that the greatest diversity is characteristic for the dendroflora of the whole territory of Vyshhorod, which is the fastest growing town, located closest to the capital. The dendrofloras of small towns were quite similar to each other. The values of similarity indices varied in a wide range: Jacquard’s index from 0.26 to 0.56 and Sørensen index from 0.41 to 0.66. The lowest degree of similarity was found with the dendroflora of the most distant Novgorod-Siverskyi town. Mainly the urban plantings require enrichment of the tree species composition, taking into account their resistance to anthropogenic impacts and climate change.