rare species

FEATURES OF THE POPULATION ORGANIZATION OF THE RARE SPECIES CEPHALARIA URALENSIS (MURR.) SCHRAD. ex ROEM. ET SCHULT (DIPSACACEAE, MAGNOLIÓPSIDA) IN THE TRANS-VOLGA AND CIS-URALS REGIONS

Authors: Abramova L. M., Ilyina V. N., Mustafina A. N., Karimova O. A.

The results of our study of 23 natural cenopopulations of Cephalaria uralensis (Murr.) Schrad. ex Roem. et Schult., a rare subendemic species of the Eastern European steppe zone, in the Trans-Volga and Cis-Urals regions (in the territory of Bashkortostan Republic, the Samara and Orenburg regions) are presented. Density indices, features of the age structure and demographic indices were studied and compared. The total density varies from 2.2 to 10.3 ind./m2. The averaged ontogenetic spectrum of C. uralensis is centered.

ON THE DISTRIBUTION OF CAULINIA MINOR (ALL.) COSS. ET GERM. (HYDROCARITACEAE, LILIOPSIDA) ON THE TERRITORY OF THE NIZHNY NOVGOROD REGION

Authors: Birykova O. V., Schestakova A. A., Belyakov E. A., Garin E. V.

The results of our analysis of the Caulinia minor distribution in the Nizhny Novgorod region on the basis of published sources, herbaria samples and the authors’ original data are presented. The species preferring water bodies with well-warmed shoals and high mineralization levels was revealed. The species entering the Red Data Book is justified due to its location on the border of the habitat. It is proposed to promote the rarity status of the species in the region; recommendations on its conservation are given.

ECOLOGICAL-PHYTOCENOTIC ASSESSMENT OF THE POPULATION STATUS OF THE RARE SPECIES DICTAMNUS GYMNOSTYLIS STEV. (RUTACEAE, MAGNOLIOPSIDA) IN THE SOUTHERN URALS

Authors: Abramova L. M., Mustafina A. N.

The results of our ecological-phytocenotic assessment of the natural coenopopulations of the rare (in Bashkortostan Republic) species Dictamnus gymnostylis Steven are given. In the Southern Urals, the species is on the northeastern border of its habitat. The ontogenetic, demographic and vitality structures of 20 coenopopulations were studied, the existence optima were found. The majority of the surveyed coenopopulations of D. gymnostylis have densities within 1 - 10 ind./sq.m and an incomplete ontogenetic spectrum, the basic ontogenetic spectrum being centered.