The present study examines the relationships between structure (floristic composition, dendrometric parameters), diversity (diversity and evenness indexes) of urban forest park stands and the ecological (soil fertility, soil moisture), environmental factors (air pollution). The study is based on the forest park stands inventory data, performed from 2012 to 2017 in Kryvyi Rih City, Central Ukraine. The floristic compositions of the urban forest park stands are poor. There are only 23 species that belong to 14 families and 12 genera. More families were represented by at least more than 2% of taxon diversity. While Ulmaceae (2 genera, 4 species-17,39 %), Fabaceae (3 genera, 2 species-17,39 %), Aсеrасеае (1 genera, 4 species-17,39 %) were the most representative families. It was established that at forest park the values of stand density varied from 490 to 660 trees*ha-1 , stem heights were from 26 to 31 m, stem diameters were from 13 to 17 cm, stand basal area were from 32 to 49 m 2 *ha-1 , stand volume were from 200 to 415 m 3 *ha-1. the values of relative stem heights were from 0,63 to 0,82 m*year-1 , relative stem diameters were from 0,31 to 0,43 cm*year-1 , relative stand basal area were from 0,80 to 1,19 m 2 *ha-1 *year-1 , relative stand volume were from 5,45 to 10,28 m 3 *ha-1 *year-1. The varied values of the forest park stands index (Shannon-Wiener diversity index from 0,75 to 1,61, Pielou"s evenness index from 0,53 to 0,86, Simpson"s diversity from 0,24 to 0,60, Margalef"s diversity index from 0,87 to 6,97) indicate the ecological instability of these woody plant communities. Current state of the urban forest park stands determined by the combined influence of ecological (soil fertility, soil moisture) and environmental factors (air pollution).

The actuality of the research is caused by the importance of understanding the laws of natural distribution of woody and shrub plant species on devastated lands of iron ore dumps of Kryviy Rih as a theoretical prerequisite for harmonizing the ecological environment of industrial regions. The aim of the research is to assess the current vital condition of woody and shrub plant species that naturally grow on devastated lands of the iron ore dump from the standpoint of the ecosystem approach. The materials of the work were the results of our own research, which were carried out according to generally accepted methods during 2020–2021 on the territory of Petrovsky waste rock dump of Kryviy Rih iron ore basin. The assessment of the current vital condition was carried out according to the method of V. A. Alekseyev. Presently,   the vegetation on Petrovsky waste rock dump, which is a model for the region, is represented by natural groups, has a fragmented character and is a sparse forest. It has been established that 32 species of woody and shrub plant species (25 genera and 15 families) naturally grow within Petrovsky waste rock dump. The current vital condition of woody and shrub plant species in the dump was assessed as «weakened» (65–71 conventional points by V. A. Alekseyev’s scale). Such numerical values of the vitality of the forest stand are 21–28% lower than the control indicators (natural groupings of Gurivka forest). Our results indicate that the ecological conditions of the devastated lands of Petrovsky waste rock dump are relatively favourable for the growth and development of woody and shrub plant species. It was found that European birch (Betula pendula Roth.), ash-leaved maple (Acer negundo L.) and acacia (Robinia pseudoacacia L.) are quite adapted to the habitat conditions of the dump. The vital condition of these species was assessed as «healthy»: 90–95 conventional points by V. A. Alekseyev’s scale.