Structure of cenothic populations of Adenophora lilifolia (L.) A. DC. in the Southern Urals and the Middle Volga region

Abstract

The study of rare plants at the level of cenothic populations throughout the range greatly contributes to the identification of the features of their biology and ecology. We carried out the identification of the features of the age and spatial structure of the Adenophora lilifolia (L.) A. DC. cenothic populations in the ecological conditions of the steppe, foreststeppe zones of the Middle Volga (Samara region) and the Southern Urals (Republic of Bashkortostan), as well as the mountainous zone of the Southern Urals. Adenophora lilifolia is included in the Red Book of the Samara region (category 3 – a rare species).The study of A. lilifolia populations was carried out in different years on the territory of specially protected territories of different rank. In determining the structure of cenothic populations, standard techniques were used. The studied cenopopulations are located on the fringes of oak-lime, birch, less often maple-linden or aspen forests, sparse forests or forest potholes. The total density of individuals varies from 0.8 to 4.2 specimens/m2. The mean values of the generative fraction in the populations are 81.1 %, the prevalent fraction is 19.3 %. The basic ontogenetic spectrum of A. lilifolia is characterized as centered. Although the share of generative individuals in all cenopopulations is high, the distribution by ontogenetic groups in the two regions differs. The average values of demographic indices indicate a fairly high stability of the species populations. Of the 14 investigated cenopopulations of A. lilifolia, according to the “delta-omega” criterion, most are mature, in addition, transitional and maturing are identified. In general, the state of the populations in the Southern Urals is fairly prosperous. All studied populations in the Samara region have a high anthropogenic load, and the number of individuals in specific habitats is low.