Features of the Biology and Ecology of Elaeagnus angustifolia L. in Southern Ural

摘要

The results of a study of the biological and ecological features of the invasive species Elaeagnus angustifolia L. in the territory of Southern Ural are provided. This species is actively naturalized mainly in river floodplains and around other reservoirs. It is included in the Black Book of Flora of Central Russia and Siberia, and black lists of the Middle Volga region and Voronezh, Orenburg, and other oblasts. The total number in the investigated coenopulations was estimated as 18 000-20 000 specimens. It is naturalized in various types of phytocoenoses, from steppe meadows to halophytic communities. Most of the investigated coenopulations are located in an arid climate with little precipitation. The northernmost coenopopulations are in more favorable natural and climatic conditions. DCA ordination of communities reveal the leading environmental factors: continental climate, moisture, soil acidity, rich soils with nitrogen, and moisture variability. E. angustifolia specimens vary in height from 2 to 8 m. Tall plants are noted mainly on unsalted habitats with sufficient moisture. Lower plants are found in saline or dry habitats. A study of reproductive biology revealed that the highest indicators of fruit parameters are observed in Aslykul, Izobilnoye, and Sol-Iletsk coenopulations, and the minimum indicators of fruit parameters are noted in the Tatarskaya Kargala coenopulation. Regression analysis of the dependence of the nucleus fraction on the fruit weight showed that, with an increase in fruit weight, a decrease in the nucleus fraction is observed. The naturalization of E. angustifolia in river floodplains negatively affect the growth, development, and resumption of native forest-forming species, which leads to irreversible consequences of the degeneration of floodplain forests.