Mechanistic Insights and Engineering Pathways of Enhanced Rock Weathering for Carbon Neutrality in Mountainous Mine Ecological Restoration

Ecological restoration of abandoned mountainous mines remains challenging because of complex geological conditions, severe substrate degradation, and long-term environmental impacts. Conventional restoration strategies primarily emphasize vegetation establishment and slope stabilization, while the potential contribution of carbon sequestration is often insufficiently considered. Enhanced Rock Weathering (ERW) has recently emerged as a promising negative-emission technology that accelerates the natural weathering of silicate minerals to remove atmospheric CO2 while improving soil quality. This paper synthesizes current knowledge on ERW and proposes a conceptual framework for integrating this technology into the ecological restoration of abandoned mountainous mines. The framework comprises four complementary dimensions: (1) Physical Restoration, utilizing fragmented rock materials to improve slope stability and substrate structure; (2) Acid–Base Neutralization, exploiting alkaline silicate minerals to alleviate acid mine drainage (AMD) and regulate geochemical conditions; (3) Pedogenic Optimization, promoting soil formation, improving soil physicochemical properties, and facilitating CO2 infiltration and mineral carbonation; and (4) Biological Synergy, enhancing plant–microbe–mineral interactions to accelerate weathering processes and support long-term ecosystem development. Drawing on existing evidence, we discuss how the use of on-site waste rock as reactive substrates may simultaneously reduce restoration-related carbon emissions, provide essential mineral nutrients (e.g., Ca, Mg, and K), and enhance carbon sequestration potential. Overall, this synthesis suggests that integrating ERW into abandoned mine restoration has the potential to simultaneously advance ecological rehabilitation and climate-change mitigation. The proposed framework provides a theoretical basis for future experimental validation, field-scale implementation, and the development of low-carbon strategies for sustainable mine restoration.