Structure of life forms and ecobiomorphs of plant communities in the Central Ciscaucasia

Abstract

The article analyzes life forms and ecobiomorphs of vegetation of steppe communities, which makes it possible to identify the relationship of plant species of the
community with the environment. The object of the study is the natural herbaceous plant communities of the Central Ciscaucasia. The research years are 2019-2021. It was identified that despite the different habitat conditions of the steppes, they are composed mainly of hemicryptophytes (herbaceous perennials) and therophytes (annual and biennial plants), which  together make 80 percent or more. During the transition from one vegetation zone to another, the structure of life forms of steppe vegetation undergoes a change. Specifically: the proportion of hemicryptophytes increases from 49 (semi-desert) to 70 (86) % (mountain, meadow steppes). The proportion of therophytes in coenosis, on the contrary, decreases from 34% (semi-desert) to 10% (mountain steppes). Analysis of the biomorphological spectrum of
steppe communities vegetation has shown that xerophytes with adaptive traits exist in conditions of constant or seasonal moisture deficiency and temperature excess. Mesophytes live in conditions with sufficient, but not excessive moisture in the soil and moderate temperatures.
Xeromesophytes and mesoxerophytes are more tolerant to moisture and high temperatures and predominate in all types of plant communities, which are considered in the article. Against the background of the continental climate, in addition to abiotic conditions, pasture load (anthropopression) has a significant impact on the structure of life forms and the biomorphological diversity of the vegetation cover of steppe communities. The similarity of the spectrum of life forms and ecobiomorphs of the beard grass steppes with the zonal ones is obvious. Despite the fact that the types of life forms (both beard grass and virgin) clearly correspond to plant zones, the communities are too heterogeneous, which is explained by differences in abiotic conditions and anthropopression in these communities.