Ontogenetic Structure and Population Dynamics of Inula grandis (Asteraceae) in Southern Uzbekistan

This study presents a comprehensive analysis of the ontogenetic structure and demographic characteristics of cenopopulations of Inula grandis (IG), a medicinally important species widely distributed in southern Uzbekistan. The research aims to assess population stability, regeneration capacity, and ecological preferences of the species under varying environmental conditions. A total of five natural cenopopulations were investigated using population-ontogenetic and phytocoenological approaches. The results demonstrated that the ontogenetic spectra of the studied cenopopulations were classified as centralized (CP 1, 3, and 5), bimodal (CP 2), and right-skewed (CP 4), reflecting different population development strategies and levels of stability. In centralized cenopopulations, middle generative (g₂) individuals predominated, accounting for 28–34% of the total population, which indicates stable population structure and active reproductive processes. The bimodal spectrum was characterized by two pronounced peaks corresponding to virginile (v) and old generative (g₃) stages, suggesting asynchronous renewal and uneven age distribution. In contrast, cenopopulations with a right-skewed spectrum were dominated by subsenile (ss) individuals, which may indicate aging populations and reduced regenerative potential. The primary distribution of I. grandis is associated with variegated and red soils, with its ecological optimum occurring at elevations of 900–1750 m a.s.l. The species exhibits well-defined phytocoenotic preferences and reaches its optimum within plant communities such as Prunus bucharica + Inula grandis + Hordeum bulbosum, Artemisia tenuisecta + Inula grandis, and Juniperus seravschanica + Inula grandis. The obtained results provide a scientific basis for assessing the current state of natural populations of I. grandis and can be used to develop strategies for sustainable use and conservation of this valuable medicinal species.