A study compared the roles of mineral and microbial attributes in the accumulation of mineral-associated organic carbon (MAOC) along a weathering gradient in volcanic soils. The research found that mineral preservation, rather than microbial residue production, was the dominant factor in MAOC accumulation. As weathering increased, mineral attributes such as clay content and reactive iron increased, enhancing mineral preservation capacity and thus MAOC accumulation. While microbial contributions to MAOC increased with weathering, mineral weathering strengthened microbial contributions by altering microbial community composition and nutrient availability. The study highlights that mineral weathering enhances long-term soil carbon storage by improving mineral preservation and microbial interactions. The findings suggest that mineral weathering, in conjunction with microbial processes, can effectively boost persistent soil organic carbon pools, offering insights for climate change mitigation strategies.A study compared the roles of mineral and microbial attributes in the accumulation of mineral-associated organic carbon (MAOC) along a weathering gradient in volcanic soils. The research found that mineral preservation, rather than microbial residue production, was the dominant factor in MAOC accumulation. As weathering increased, mineral attributes such as clay content and reactive iron increased, enhancing mineral preservation capacity and thus MAOC accumulation. While microbial contributions to MAOC increased with weathering, mineral weathering strengthened microbial contributions by altering microbial community composition and nutrient availability. The study highlights that mineral weathering enhances long-term soil carbon storage by improving mineral preservation and microbial interactions. The findings suggest that mineral weathering, in conjunction with microbial processes, can effectively boost persistent soil organic carbon pools, offering insights for climate change mitigation strategies.