Drivers Affecting the Carbon Budget of Russian Terrestrial Ecosystems (1960–2020): Climate Change, Management, and Disturbances

Russia, the largest country on Earth, spans 17.1 million km² and contains 21% of the world’s forests. Between 1975 and 2020, the country experienced warming at a rate 2.5 times the global average, accompanied by moderate but uneven increases in precipitation. All natural zones of the northern hemisphere are represented within Russia’s borders, and two-thirds of its territory is underlain by permafrost. This permafrost contains over 500 Pg of carbon within the upper 3 meters, including vast stores of methane and hydrates in northern Pleistocene “yedoma” deposits, presenting a potential risk of a "methane bomb" under intensive warming. Climate variability has increased since the mid-1970s, driving changes in natural disturbance regimes, particularly in forests. Additionally, social and economic upheavals following the October Revolution (1917) and the collapse of the Soviet Union (1992) have hindered Russia’s transition to sustainable forest management.Comprehensive land-cover data for Russia have been available since 1960, coinciding with the country’s first forest inventory. Since the 1980s, the widespread use of remote sensing has accelerated the accumulation of information about ecosystem functioning, particularly regarding forests and their biospheric roles. Extensive databases, models, and maps have been developed to improve understanding of carbon budgets. Over the past 30 years, the International Institute for Applied Systems Analysis has advanced a methodology for comprehensive and verifiable carbon accounting (CVCA) for Russia, based on principles of applied systems analysis. This approach integrates diverse datasets—including ground-based and remote sensing data—on terrestrial ecosystems, climate, soils, landscapes, management, and disturbances. The Integrated Land Information System (ILIS), which incorporates a Hybrid Land Cover (HLC) GIS with a 150-meter resolution, serves as the spatial foundation for this methodology. The ILIS-HLC system has resolved key informational and methodological challenges in carbon accounting for Russian forests and enabled the integration of bottom-up (landscape-ecosystem) and top-down (atmospheric inversion) approaches within the CVCA framework.This presentation examines the primary drivers influencing the carbon budget of Russia’s terrestrial ecosystems from 1960 to 2020, with a focus on forests. Key topics include: (1) The impacts of climate change on ecosystem sustainability and productivity. (2) The dynamics of natural and anthropogenic disturbances, particularly wildfires and biogenic factors. (3) The role of management in transitioning Russian forests toward sustainable forest management practices.The analysis shows that Russia’s terrestrial ecosystems have acted as a net carbon sink of 500–600 Tg C/year over the past three decades, largely due to forest ecosystems, though this sink decreased by the late 2010s. The presentation also discusses uncertainties within the CVCA framework and highlights areas requiring further research and refinement.