Dynamic of soil organic carbon pools following afforestation in coastal saline-alkali land: A model-data fusion study

By fusing field chronosequence data with the Biome-BGC model, we uncovered a continuous, long-term trajectory of soil organic carbon (SOC). The most striking finding is a distinct "triphasic" pattern: counterintuitively, afforestation initially causes a net loss of soil carbon for 0-15 years, driven by the decomposition of stable mineral-associated organic carbon (MAOC) due to planting disturbance. After this period, the system enters a phase of sustained accumulation, fueled by the rapid buildup of labile particulate organic carbon (POC) in topsoil and gradual MAOC stabilization in subsoil.