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The main objective of the study was to evaluate the population characteristics of Betula nana under different anthropogenic influences. The study was conducted in the vicinity of the exploited Šepeta peatland (northeastern Lithuania). The population status of B. nana was determined by comparing the ramet density and morphology (height, branching, and leaf size), the age structure, the number of generative ramets, and their flowering characteristics in four study areas at different distances from the exploited peatlands and in different habitats. Around 20 environmental factors were included in the analysis, covering water levels, peat, and vegetation characteristics. Shading, drainage and increased amounts of nitrogen in the habitats are the main factors contributing to the differences and structure of B. nana cenopopulations. Although taller ramets with larger leaves are observed under the changed conditions as an adaptation to shading, the negative anthropogenic effects in the most affected habitats are reflected in a reduction in the number of flowering ramets, lower vegetative regeneration, and an increase in the number of dead twigs on mature ramets. [ABSTRACT FROM AUTHOR]

The distribution, morphometric and population characteristics of the invasive species Lupinus polyphyllus Lindl. in Republic of Bashkortostan are analyzed. Twenty-five localities of the species are identified and 11 invasive populations are examined in five districts of the republic. It is shown that the main vector of L. polyphyllus invasion is the drift of the species from horticultural crops, and spontaneous species dispersal along the roads is less common. The density of L. polyphyllus plants in cenopopulations ranges from 4.3 to 14.5 ind./m2. The aboveground biomass of the species can reach 1 kg per 1 m2 or more. The proportion of the species in the community ranges from 55.1 to 88.8%; the species dominates in most communities. When introduced into meadow phytocenoses, it forms a derivative community of Lupinus polyphyllus [Arrhenatheretalia elatioris]. It is established that the maximum values of the parameters are typical of populations growing in more favorable moisture conditions. The highest indicators of parameters are noted in the Bulat-Elga and Changakul cenopopulations; the minimum ones are in the Neftekamsk and Urazaevo cenopopulations. One generative shoot gives from 13 to 95 fruits and from 56 to 760 seeds; the total productivity of one plant reaches 4543 seeds. The vitality assessment shows that four cenopopulations are prosperous, one cenopopulation is equilibrium, and six are depressed. An increase in the number of localities of L. polyphyllus in the Cis-Urals of the Republic of Bashkortostan is predicted in the coming years. [ABSTRACT FROM AUTHOR]

Variation in morphometric parameters of the poorly studied rare species Cephalaria uralensis (Murr.) Schrad. ex Roem. et Schult. has been studied at the northern boundary of its range, in the Southern Urals (Bashkortostan). The species in the region grows in four types of steppe communities of the class Festuco-Brometea. Variation in the majority of parameters is within the species reaction norm. The most variable parameters are the numbers of vegetative and generative shoots and the number of inflorescences per shoot. As shown by discriminant analysis, all 16 cenopopulations included in the study significantly differ from each other (Wilks' λ = 0.21), with most of them being morphologically and structurally uniform. The state of local C. uralensis appears to be satisfactory, and this species is not at serious risk for extinction in the territory of Bashkortostan. [ABSTRACT FROM AUTHOR]