Digital soil mapping of soil organic carbon in flat areas based on multi-temporal remote sensing phenological variables.

increased by 0.08, CCC increased by 14.0%). RFRK model simulation results showed that from 2013 to 2023, SOC exhibited an overall increasing trend. There were differences in the magnitude of change across different regions, with the largest increase in the northwest region, reaching 80.6%. In summary, introducing multi-temporal phenological variables in flat areas could improve the accuracy of SOC digital soil mapping and provide a methodological reference for refined mapping of SOC in flat areas.