Agrochemical compositions of soils and rhizosphere microorganisms of Rosa potentilliflora Chrshan. et M. Pop. in eastern and central part of Zailiyskiy Alatau

Abstract Background This study focuses on the agrochemical properties of soils and microbial communities in the rhizosphere of the narrowly endemic species Rosa potentilliflora in the mountain ecosystems of the Zailiyskiy Alatau (Kazakhstan). The goal was to evaluate the influence of soil conditions on the composition and activity of rhizosphere microbiomes, as well as to identify key factors shaping their biodiversity. The study examined three distinct locations: Shilisai gorge, Syugaty massif, and Turgen gorge, which differ in altitude, vegetation cover, and soil proporties. Methods The research involved analyzing agrochemical parameters such as humus content, pH, and mineral compounds (bicarbonates and sulfates). Microbiological analysis was conducted to assess the microbial population, focusing on nitrogen-fixing bacteria ( Azotobacter spp.) and actinomycetes ( Coerulescens , Ruber ). The study also explored the correlation between humus content and the abundance of nitrogen-fixing microorganisms. The microbial density was quantified in terms of colony-forming units (CFU) per gram of soil. Results The agrochemical analysis revealed significant differences in humus content (2.08–12.9%), pH (6.97–8.93), and mineral composition. The microbiological analysis indicated high microbial populations (ranging from 2.3 × 10 6 to 3.3 × 10 7 CFU/g), with nitrogen-fixing bacteria Azotobacter spp. dominating (80–94%) and the presence of actinomycetes ( Coerulescens , Ruber ). A positive correlation was found between humus content and the abundance of nitrogen-fixing bacteria ( r = 0.82, p < 0.01), highlighting the importance of organic matter for sustaining microbial activity in the rhizosphere. Conclusions The study demonstrates the adaptive potential of Rosa potentilliflora to extreme conditions in mountain ecosystems and its significant role in forming unique microbial communities. The actinomycete strains identified show considerable biotechnological potential, opening opportunities for the development of bioproducts and sustainable land management strategies. The findings contribute to the understanding of ecological interactions in the rhizosphere of rare plant species and can be applied to biodiversity conservation in Kazakhstan’s mountain ecosystems.