ECOLOGICAL AND BIOLOGICAL CHARACTERISTICS OF SHRUBS IN THE URBAN ECOSYSTEMS OF KHERSON (UKRAINE)

Abstract

Inventory of the shrubs species composition in the urban ecosystems in the city of Kherson revealed 129 species belonging to 65 genera, 26 families, 2 classes and 2 divisions. Major families of the studied shrub dendroflora are Rosaceae Juss. (36 species representing 27.9% of the total number of species), Caprifoliaceae Juss. (15 species, 11,6%), Oleaceae Lindl. (15 species, 11,6%), Fabaceae Lindl. (10 species, 7,8%), Berberidaceae Juss. (6 species, 4,7%), Hydrangeaceae Dumort. (4 species, 3,1%). Other families are represented by fewer species. The most represented here are genera Lonicera (10 species, 7,8%), Spiraea and Syringa (8 species both, 6,2%), Cotoneaster (6 species, 4,7%), Berberis (5 species, 3,9%), Viburnum (5 species, 3,9%). The analysis of growth patterns has established 7 types. The group of upright deciduous shrubs (98 species, 76,0%) and upright evergreen shrubs (17 species, 13,2%) are the largest ones. Amongst the life form groups, the woody plants sharply dominate with their share of 94,6%, while the semi-woody plants are represented by 7 species only (5,4%) in the plantation of Kherson. Most plants are upright. The predominant plants are deciduous ones (106 species), while the group of evergreen shrubs are represented by 23 species (17.8%). It is established that according to the geographical structure the species of the South Palaearctic (34 species, 26,4%), European-Mediterranean-Iranian-Turanian (19 species, 14,7%), European (12 species, 9,3%), European-North American (11 species, 8,5%) and Euro-Siberian (11 species, 8,5%) origin dominate. The assessment of winter-hardiness showed the predominance of species resistant to low temperatures (117 species, 90,6% of the total), which little or almost no damage survive the complex of adverse factors in winter. 6 species (4,7%) have been identified as winter-hardy and the same quantity (6 species) as low-winter-hardy plants. The assessment of drought tolerance showed that most shrub species are drought-resistant (105 species, 81,4% of the total species) in landscaping. The number of moderately drought-tolerant species that partially lose their ornamental features during dry periods as well as drought-susceptible species is negligible.