Ornamental woody plants assortment expansion in landscaping the cities of Southern Ukraine

Abstract

In the context of global climate change, increased anthropogenic pressure, the discomfort of urban areas due to air pollution by vehicles and industrial enterprise emissions, landscaping of urban areas is of particular importance. Green spaces in ecosystems perform several environmental functions. Their key functions are sanitary-hygienic, recreational, artistic, and decorative. The sanitary-hygienic function of the woody and herbaceous plants system of the urbanized territories in the south of Ukraine is air purification and ionization, wind regime stabilization, and cooling the urban "heat island"; oxygen saturation of the urban environment; absorption of atmospheric air pollutants; the increase of relative humidity and decrease of its daily and seasonal fluctuations; shading; reducing noise pollution. The plants are biological air and soil filters. In urban areas, they also act as components of landscape architecture that create the natural landscape environment. Therefore, the landscaping issues are relevant to the cities of the south of Ukraine. General landscaping facilities of southern Ukraine were created in the mid-twentieth century. Therefore, the plantations have reached the overmature age and need immediate replacement. Selection of wood species should be made according to several criteria: durability, disease and pest resistance, resistance to harmful substances in the atmosphere, winter hardiness and drought resistance, as well as high decorative qualities. The introduction of evergreen plants is recommended to ensure the seasonal aspect of landscaping. Typically, the local tree species that grow successfully in these conditions are the basis of the introduction. Kherson is located in the dry-steppe subzone of the Steppe zone of Ukraine; therefore, tree vegetation is not characteristic for the urban ecosystem of the city. There are few aboriginal woody plants species. Accordingly, the selection of the principal, as well as the additional assortment of plants under these conditions, is quite a difficult task. The introductions adapted to the conditions of southern Ukraine are mainly used to create parks and gardens.