Bacterial functional traits: a key driver of soil organic carbon dynamics during reductive soil disinfestation

) copy number, co-occurrence networks, and functional profiles. The results showed that microbial necromass carbon increased markedly after RSD treatment and accounted for up to 75% of the total SOC. Compared to wheat straw, soybean straw amendment resulted in higher relative abundances of Firmicutes (47.70%), Halobacterota (506.99%), and Euryarchaeota (1671.36%), intensified anaerobic conditions during RSD, improved suppression of aerobic fungi, and preferentially promoted the accumulation of fungal necromass carbon (33.25%). Conversely, the wheat straw treatment induced moderate anaerobic conditions, less pronounced than with soybean straw but stronger than the control, while sustaining higher bacterial abundance and promoting more robust bacterial succession, thereby preferentially leading to accumulation of bacterial necromass carbon (141.74%). These findings underscore the important role of bacteria functional traits in mediating carbon sequestration under anaerobic straw incorporation and provide new insights for optimizing organic amendment strategies in RSD practices to enhance soil carbon sequestration efficiently.