Shamray M. Assessment of the recreational -landscape-forming arboreal resource of urban-territory parks of the steppe zone

The dissertation is devoted to the ecological, floristic characteristics and evaluation of the recreational-landscape-forming arboreal resource of parks of urban territories of the steppe zone. Parks, as a specific type of urban space, are a reflection of cultural traditions in the historical sense and works of garden and park art. They have an important recreational function, and their green areas create comfortable conditions for, in particular, recreation and life in a modern urbanized environment in general. Parks in the urban areas of the steppe zone are characterized by a heterogeneous (and relatively simplified due to the aridity of the climate) taxonomic composition of tree and shrub species, the representatives of which mostly belong to introduced species. In addition, the city's parks belong to its specific functional zones and have a different level of recreational load in them. This determines the urgency of finding out the floristic diversity, self-regeneration of tree species, homogenization of plantings of park territories, which is solved in the presented study. Therefore, one of the functions of the parks is the preservation of biodiversity, since the floristic composition of the parks in terms of the number of species can reach 20–30% of the flora of the region. Ecological value recreational-andscapeforming arboreal resource of parks in the conditions of the steppe grows especially in the summer hot and dry period. In this regard, the presence of the arboreal element of park areas of cities with an uncomfortable summer climate is one of the criteria qualities of urban territory. Research conducted within two functional zones, allocated in accordance with the zoning of urban territories: 1) settlement zone and the urban center of the urban area (Dnipro - Oles Honchar DNU Botanical Garden, Yuri Gagarin Park, Taras Shevchenko Park, park named after Bohdan Khmelnytskyi, green zone of Karuna Street, Amur-Nizhnyodniprovsky district); 2) landscape and recreation area (city of Dnipro - forest park Druzhba, Park of Cossack glory - Kyrylivka, Tunelna Balka tract; city of Primorsk, Zaporizhzhia region - park area of recreation center "Azov") The object of research is tree plantations of parks (with a heterogeneous level of recreational load) of two functional zones of urban areas in the conditions of the steppe. During the work, the following methods were applied: floristic research methods – determination and clarification of the taxonomic composition, selection of the adventitious component of the 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, applied methods of determining soil biological activity, statistical methods of data processing (descriptive statistics, method of multiple comparisons of averages by criterion Tukey, variance and correlation analyses). Taxonomic definitions of plants are given in accordance with modern botanical nomenclature. Soil samples, native and herbized parts of tree and shrub plants served as material for the research . It was established that in the parks of the settlement zone and the city center of the urban area of Dnipro, on test plots with different levels of recreation, stands of trees are represented by 27 species, which are part of 19 genera and 15 families. In terms of quantity, the flora of the studied parks is mostly saturated with representatives of the families Sapindaceae, Salicaceae, Oleacea and Simaroubaceae. The relative number of self-regenerating introducers (park average) ranges from 17.7% (B. Khmelnytsky Park) to 62.4% (T. Shevchenko Park). The number of selfregenerating introducers is higher in the trial areas of the studied parks with a strong level of recreation (from 66.0% to 96.2%). Ailanthus altissima ( family Simaroubaceae ), Acer negundo (family Sapindaceae ), Gleditsia triacanthos, Robinia pseudoacacia (family Fabaceae ), which indicates a constant invasion of alien species into the local flora and a potential threat to natural floristic diversity. The correlation coefficient between the number of native and introduced species is statistically significant and ranges from 0.76 to 0.89 for parks named after T. Shevchenko, botanical garden of DNU named after O. Honchar (together with Gagarin Park) and the green zone of St. Karuna, and for B. Khmelnytsky Park it turned out to be low and statistically insignificant. In the parks of the landscape-recreational urban territory on trial areas with different degrees of recreational load in the conditions of the cities of Dnipro and Primorsk, stands of trees are represented by 34 species belonging to 22 genera and 25 families.