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Background. Comparison of ontogenetic indicators of local populations of the yellow flax plant Linum flavum L., rare for the Penza region, was aimed at assessing their current state as the basis for further monitoring and development of measures to protect the species to preserve the biodiversity of the Penza region. Materials and methods. Under the conditions of the protection regime (the natural monument “Urochische Cherdak”) and in the conditions of the restoration of steppe communities on fallow land (the Ukhtinsky steppes tract), the density, numbers, and ontogenetic structure of local populations of yellow flax were studied, as well as the phytocenotic location of the species and its contribution to the structure of communities at different stages restorative succession. Results. In the studied communities of true and meadow steppes, steppe and true meadows, Linum flavum forms a caudex facultative- root-sprouting biomorph. Shows traits of explerence. When the vegetation cover is highly dense, it acts as an assectator with a projective cover of 2–4 %; populations have a low density (2.5 pcs/m2). In disturbed communities it dominates and co-dominates (projective cover 20–25%), increasing the density by an order of magnitude due to individuals of the pregenerative period. Ontogenetic spectra in both cases are two-peaked – with a maximum in juvenile and generative individuals; in weakly disturbed communities, the main contribution to the structure is made by mature and old generative individuals, and in fallows – by juvenile individuals (populations according to the “Δ – ω” classification are transitional and young, respectively). Conclusions. The current state of both local populations is stable. To preserve the population of Linum flavum and other rare species (Salvia verticillata, Senecio schvetzovii, Aster amellus, Gypsophila altissima) in the vicinity of the village. In Ukhtinka village it is rational to limit economic activity by organizing the natural monument “Ukhtinskiye stepi”. |
