REPRESENTATIVES OF THE FAMILY SALICACEAE MIRB. IN THE GREEN SPACES OF THE CITY OF KRYVYI RIH (DNIPROPETROVSK REGION)

Abstract

Introduction. To stabilize and optimize the urban environment, it is possible only by maintaining a high level of plant activity. In the system of green spaces of cities, woody plants play the main role in shaping the environment. Among the deciduous woody plants of the temperate zone of the Northern Hemisphere, species of the family Salicaceae Mirb. are among the most used in landscaping. Fast growth, phytoncide qualities, resistance to air pollution and unpretentiousness to soils – all this contributed to the use of Salicaceae in garden and park architecture. The study of their ecological and aesthetic role in modern urban complexes is timely and relevant. Aim. The purpose of our work was to investigate representative species of the family Salicaceae Mirb., used in the landscaping of the city of Kryvyi Rih, as well as their vital state and morphometric characteristics. Methods. The study of the real state of green spaces was carried out by the method of route surveys using the methods of landscape taxation. The degree of spread of a species or a cultivar was determined by the occurrence rate of the species, which was calculated by the ratio of the number of parks (squares) with a given species to the total number of them, expressed as a percentage. The viability of trees was determined according to the scale of viability of tree species in protected plantations by L. Savelyeva. Main results. Among the angiosperms, one of the most abundantly represented in the landscaping of parks and squares of Kryvyi Rih is the family Salicaceae Mirb. In the city’s green spaces, species and cultivars from two genera are widely used. The genus Salix L. is represented by 5 species Salix acutifolia Willd., S. alba L., S. babylonica L., S. exelsa S. G. Gmel., S. fragilis L. and 2 decorative forms of S. alba ‘Vitellina pendula’ Rehd., S. matsudana Koidz. ‘Tortuosa’. At the same time, the genus Populus L., in the green spaces of the city, is represented more widely and includes 9 species: Populus alba L., P. balsamifera L., P. bolleana Lauche, P. deltoides Marsh., P. italica (Du Roi) Moench, P. nigra L., P. simonii Carr., P. tremula L., P. trichocarpa Torr. et Gray and 2 hybrids – P. x berolinensis Dipp., P. x wettsteinii. In the course of research, it was ascertained that willows and poplars in the city’s parks are used unevenly, therefore, according to the degree of distribution, they can be divided into three categories: I category – the most common species that occur in 32-50 landscaping objects (degree of distribution – 27.6-43.1%); II category – moderately common species occurring in 7-20 landscaping objects (prevalence rate – 6–17.2%); ІІІ category – rare species growing in 1-4 landscaping objects (degree of distribution – 0.9-3.5%). The first category includes P. italica (Du Roi) Moench, P. deltoides Marsh., P. bolleana Lauche, P. nigra L. and S. alba ‘Vitellina pendula’ Rehd., which grow in almost half of the studied parks and city parks. According to the predominance of types of plantings, the following series can be built: group plantings → individual specimens → plantings in rows → massifs → alley plantings. The second category includes P. simonii Carr., S. alba L., S. babylonica L., S. matsudana Koidz. ‘Tortuosa’, S. fragilis and P. alba L. The third category consists of rare species: S. acutifolia Willd., S. excelsa S. G. Gmel. and P. tremula L., P. trichocarpa Torr. et Gray, P. balsamifera L. and the hybrid P. x wettsteinii. For the first time, information on the distribution of willows and poplars was studied and summarized in the cultivated coenoses of the Right Bank Steppe of the Dnieper region, using the example of a large industrial city, and their main morphometric characteristics were determined. The obtained data make it possible to improve planning for the use of promising species, hybrids and forms of the family Salicaceae Mirb. with the aim of enriching the value of green spaces of parks and squares in the conditions of the Right Bank Steppe of the Dnieper region. Most representatives of the family Salicaceae Mirb. passed the initial test in the conditions of the introduction area, showed satisfactory adaptability and average points of life status. The exceptions are the poplar cultivars P. ‘Hradizhzka’, P. ‘Sacrau-59’ and P. ‘Keliberdynska’, which at the age of 20 years are in excellent condition and have the highest viability rate.