Microbial Community Traits and Necromass Dynamics Shape Soil Carbon Accumulation

. Conversely, inorganic fertilisation induced an oligotrophic 'mining' strategy, in which microorganisms upregulated the degradation of complex organic matter under carbon-limited conditions, restricting sustained SOC accumulation primarily to the MAOC pool. A global meta-analysis of field experiments (0-120 years) corroborated these temporal trajectories across diverse soil types, showing that SOC under organic fertilisation increases in a time-dependent manner, reaching a 77% gain after 80 years (three-fold greater than under inorganic inputs). Overall, organic fertilisation enhances total SOC via POC and MAOC accumulation, whereas inorganic fertilisation mainly increases MAOC. Long-term SOC persistence depends not only on carbon inputs, but also on microbial community traits and necromass dynamics, suggesting that aligning nutrient inputs with these biological mechanisms is critical for sustainable carbon sequestration.