Аннотация:dern climate change. The analysis of stable carbon isotope (δ13С) composition is one of theapproaches to understanding this dynamics. The study was carried out in the landscapes of the southeastern slope and foothills of the Primorskii Range, characterized by contrasting physico-geographical conditions. Climatic parameters, spatial variations in the composition of stable carbon isotopes and their distribution in soil profiles, and soil physicochemical properties controlling carbon dynamics have been analyzed. The soil humus horizons formed in mountainous tundra and steppe landscapes manifest the highestδ13С values (–24.72 and –23.97…–24.75‰); whereas the lowest (–25.61…–27.18‰) values are registeredin the mountainous taiga soils. Based on the calculation of linear dependence between δ13С values and thetotal carbon content in soil, which varies with the depth, the carbon turnover intensity was determinedusing the slope of linear regression. It was revealed that under the contrasting conditions of mountainoustundra and steppe landscapes, the climate (deficiency of heat and moisture) has a significant impact on theintensity of organic matter transformation, blocking the effect of edaphic (soil profile) factors. Under morefavorable climatic conditions of mountainous taiga landscapes, the dynamics of organic matter in soils iscontrolled mainly by edaphic factors