BELT DISTRIBUTION OF VEGETATION IN THE BASIN OF THE AT-BASHI RIVER OF THE INNER TIEN-SHAN OF KYRGYZSTAN

Geobotanical characteristics of the main types, subtypes, formations and groups of vegetation associations in the section of the altitude profile are given. Kyrgyzstan is a high-mountainous country of Central Asia, which is located in the center of the mountain systems of Tien-Shan and Pamir-Alay. Up to 90% of its territory is raised to absolute heights of more than 1500 m. Vegetation cover of Kyrgyzstan is located in a system of vertical belts. Steppes and meadow-steppes are the most widespread in the At-Bashi river basin. Among them there are bunchgrass steppes and meadow-steppes, dry steppes and meadow-steppes with a significant share of wormwood and drought-resistant motley grasses, as well as mountain meadows. Among mountain meadows there are tall, medium and low grass meadows. High grass meadows, developed in low mountains and middle mountains, in the north and south differ in the species composition of plants. In the northern regions, the following species are of major importance: Dactylis glomerata, Bromus inermis, Elytrigia repens, Brachypodium pinnatum ; representatives of the genera: Poa, Vicia, Thalictrum . The largest share of the steppe vegetation is occupied by plants, which according to the requirements to heat and moisture occupy an intermediate position between desert plants and meadows. The basis of vegetation of steppes is formed by species of genera of turf cereals: Stipa, Festuca , Ptilagrostis with very characteristic hairy and blue-gray leaves. Steppes, unlike deserts and semi-deserts, are characterized by a greater richness of plant species and density of vegetation. Steppes serve as good pastures.