Long-term conservation policy promotes substantial carbon storage in riparian forests of the southern Russian Far East

Riparian forests are among the world's most productive yet vulnerable ecosystems. However, their climate-regulating role, especially in undisturbed regions, remains poorly understood. In these riparian forests, high carbon stocks co-occur with rapid carbon turnover, reflecting the dynamic nature of carbon cycling in natural forest ecosystems. We integrated field measurements of carbon pools and fluxes in riparian forests of the southern Russian Far East, including the development of 14 local allometric equations for biomass assessment, with landscape-scale modeling to quantify their carbon-regulating function. Total ecosystem carbon stocks were high, ranging from 154 to 335 t C ha−¹. A key feature is the dominance of living biomass in the ecosystem carbon pool, accounting for up to 80% in the studied forests. Despite these large stocks, the ecosystem is characterized by high metabolic activity, evidenced by intensive soil respiration (up to 10 t C ha−¹ yr−¹) and rapid litter turnover. Our results indicate that long-term conservation of these forests has contributed to the development of substantial carbon stores in these ecosystems and highlight the importance of maintaining their protected status.