No abstract

Abstract. This paper deals with the morphological variability of plants as well as the composition and structure of Trifolium repens L. coenopopulations as a valuable honey plant, an agricultural plant and the plant which is used in medicine. This plant is rich with ascorbic acid, carotene, contains alkaloids, glycosides and other substances. T. repens coenopopulations with difference in density and structure are formed under the influence of ecological and coenotic conditions. Eleven T. repens coenopopulations in various landscape regions in the Republic of Tatarstan were analyzed. Environmental factors characterizing habitats, plant morphological status by 9 parameters, density and vitality structure of coenopopulations were investigated. The results showed that slightly acidic, fresh soils with an above average mineral content are formed in the subtaiga subzone. In the composition of the broad-leaved subzone, the degree of soil moisture decreases to fresh and periodically dry, the content of mineral nitrogen increases from average in the north to higher than the average in the south, soil acidity, on the contrary, decreases from slightly acidic to neutral. The habitat conditions that developed in the north of the broad-leaved subzone are most optimal for the development of T. repens coenopopulations, because plants in these conditions have the largest biomass parameters. This allows us to recommend collecting T. repens coenopopulations in the north of the broad-leaved subzone for medical purposes.