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The state of seed self-regeneration of woody plants of Kyrylivka Park (Dnipro, Ukraine) in areas with a strong, moderate and non-existent level of recreational load was studied. Floristic methods (estimates of species richness, determination of floristic community and homogeneity),methods of ecological analysis of vegetation, physico-chemical methods of soil analysis, statistical methods are applied. It was establishedfor the first time that in Kyrylivka Park, artificial stands are capable of forming a sufficient amount of viable undergrowth of autochthonous (53.5%) and introduced (46.5%) species. The amount of tree growth of adventitious plants in the areas according to the level of recreational load is distributed as follows: with no load –32.2% of the number of self-regenerating trees, with moderate –41.3%, with strong –89.7%. The indices of species richness of Margalef and Menkhinik of self-regenerating tree species for the site with a strong recreational load turned out to be the largest (at the expense of adventitious species) compared to the sites with a moderate recreational load and without it. The calculated Koch index of biotic dispersion (40.0%) indicates a certain process of floristic homogenization of the tree stand in the investigated territory of the park. The correlation coefficients between the number of self-restored allochthonous and autochthonous tree species for the studied areas with strong, moderate and absent recreational loads are significant (0.90, 0.92 and 0.88 respectively).The need to analyze and forecast the possible remote consequencesof the introduction of alien species in the composition of the dendroflora is emphasized.

Purpose. Biodiversity assessment and clarification of the trend towards homogenization of the dendroflora of the Shevchenko Park (Dnipro, Ukraine). Methods. Floristic methods of research are applied - elucidation of the taxonomic composition and selection of the adventitious fraction of dendroflora, methods of species richness assessment (according to the Menkhinik index and Margalef index), determination of floristic commonality (according to the Jaccard index) and floristic homogeneity (according to the Koch index of biotic dispersion), methods of ecological analysis (by biomorphs and ecomorphs), physical, physicochemical, chemical methods of soil analysis, soil biological activity, statistical methods of data processing (descriptive statistics and correlation analysis). Results. It was established that artificial stands of trees in the Shevchenko Park are capable of forming a sufficient amount of viable undergrowth of autochthonous and introduced (adventurous) species, the ratio of which is 37.0% to 63.0%. The amount of tree growth of adventive sites in the areas according to the level of recreational load is distributed as follows: with no load - 38.5% of the number of self-regenerating trees, with moderate - 68.2%, with strong - 80.5%. The indexes of species richness of Margalef and Menkhinik of self-regenerating tree species for the site with a strong recreational load turned out to be the largest (due to adventitious species) compared to the sites with no and moderate recreational load. Koch index of biotic dispersion is 50.0%. Correlation coefficients between the number of allochthonous and autochthonous tree species that have self-regenerated for the studied areas with strong, moderate and no recreational load are statistically significant (0.73, 0.76, 0.77 respectively). Conclusions. On the territory of the investigated areas of the park, there are 14 tree species capable of seed self-regeneration, which taxonomically belong to 12 genera and 10 families. Of them, 9 adventive species were registered, represented by 9 genera and 7 families with the leading family Sapindaceae. The calculated index of biotic dispersion testifies to the presence of a process of floristic homogenization of the forest stand on the territory of the park. As part of the adventitious fraction of the self-regenerating dendroflora, there is an increased invasion of Ailanthus altissima and the occurrence of such neophyte species as Celtis occidentalis and Acer negundo, which indicates the penetration of alien species into the local flora and a potential threat to natural floristic diversity.

The paper presents the study of the state of seed self-regeneration of woody plants of the Tunelna Balka Tract in the conditions of the city of Dnipro, Ukraine. Three sites with different levels of recreational load (strong, moderate and absent) were studied. The following floristic methods of research were applied – elucidation of the taxonomic composition and selection of the adventitious fraction of dendroflora, methods of species richness assessment (according to the Menkhinik index and Margalef index), determination of floristic commonality (according to the Jacquard index) and floristic homogeneity (according to the Koch index of biotic dispersion), methods of ecological analysis (by biomorphs and ecomorphs), physical, physicochemical, chemical methods of soil analysis, statistical methods of data processing (descriptive statistics and correlation analysis). We determined that in the Tunelna Balka Tract, cultured stands are capable of forming a sufficient amount of viable young plants of autochthonous and introduced (adventurous) species, the ratio of which is 47.4% to 52.6%. The number of young woody advent plants in the areas according to the level of recreational load was distributed as follows: with no load – 38.8% of the number of self-regenerating trees, with moderate – 29.0%, with strong – 69.1%. The Margalef and Menkhinik species richness indices of self-regenerating tree species for the site under heavy recreational load was the lowest compared with the sites subject to no and moderate recreational loads. Evaluation of the qualitative commonality of the species composition of the experimental sites with self-regenerating tree species showed the presence of a trend towards maintaining the diversity of the flora of the sites, which is achieved precisely due to the different level of recreational load. The calculated Koch index of biotic dispersion (26.1%) indicates a sufficiently low level of floristic homogenization in the studied territory of the tract. The correlation coefficient between the number of introduced and self-regenerating autochthonous tree species for the site under no recreational load turned out to be insignificant and weak (0.27), for sites with a moderate and strong level of recreational load – significant and strong (0.96 and 0.91, respectively). Therefore, the studied areas have a low degree of floristic homogeneity, which is confirmed by the low index of floristic commonality. We determined that the species richness of the self-regenerating dendroflora of the studied territory depends on the level of recreational load, and its strong level determines the low species richness. We should emphasize the need to analyze and predict the possible remote consequences of the introduction of alien species in the composition of the dendroflora.