Mapping soil organic carbon in European forests under future climate scenarios

Forest soils play a critical role in the global carbon cycle and in mitigating greenhouse gas emissions. However, the storage of soil organic carbon (SOC) in European forests and its future dynamics remain unclear. This study applied a digital soil mapping (DSM) approach based on LUCAS soil datasets, using machine learning models to predict SOC’s current and future spatial distribution in European forests. The analysis incorporated sixteen key environmental variables derived from multi-source remote sensing and ecological data, identified through the Boruta feature selection method, highlighting soil properties, climate, and vegetation as the dominant factors shaping SOC distribution. The results revealed that SOC stocks are currently concentrated in northern Europe, the UK, and the Alps, with temperate forests exhibiting a notable increase in SOC stocks as forest age increases. Under the high-emission pathway (SSP585), SOC storage was projected to increase by 2100, particularly in young forests. This study provides a baseline assessment of SOC storage in European forests and insights into its future trends, offering valuable guidance for forest management and carbon sequestration strategies.