THE CURRENT ECOLOGICAL STATE OF THE PASTURE ECOSYSTEMS OF THE ILOVLINSKY SANDY MASSIF

The spring features of the Ilovlinsky sandy massif phytocenoses are characterized as follows. 147 species from 24 families have been identified on the flat and sloping low-lying, deep-humus, deep–sea sediments of the sandy steppe of the III above-floodplain terrace. 107 species from 22 families were found on the slightly overgrown bumpy-hilly sands of the II above-floodplain terrace. On the overgrown bumpy-hilly semi-broken sands of the II above-floodplain terrace there were 153 species from 31 families. The summer features of sandy phytocenoses are characterized as follows. 163 species from 27 families were identified on the flat and sloping low-lying, deep-humus, deep–sea sediments of the sandy steppe of the III above-floodplain terrace. 127 species from 25 families were found on the slightly overgrown bumpy–hilly sands of the II above-floodplain terrace. 174 species from 35 families were on the overgrown bumpy-hilly semi-broken sands of the II above-floodplain terrace. The Asteraceae and Poaceae families are distinguished by the largest number of species found, both in spring and summer. The average yield of air-dry phytomass on flat and sloping low–lying, deep–humus, deep-sea sediments of the sandy steppe on the III above-floodplain terrace was 174 g/m2 in May, 388.3 g/m2 in June, 286.7 g/m2 in July, 467.2 g/m2 in August. On the slightly overgrown bumpy-hilly sands on the II above-floodplain terrace, the average yield of air-dry phytomass in May was 278.6 g/m2, in June – 301.6 g/m2, in July – 59 g/m2, in August – 320.8 g/m2. On the overgrown bumpy-hilly semi-broken sands on the II above-floodplain terrace, the average yield of air-dry phytomass in May was 310.3 g/m2, in June – 403.2 g/m2, in July – 145.3 g/m2, in August – 321.7 g/m2. A strong direct dependence of the change in air-dry phytomass (g/m2) and PP (%) of the vegetation cover of the Ilovlinsky sand massif on the hydrothermal coefficient was revealed.