Mineral carbon pump in the Earth system

The balance between the degradation and preservation of organic carbon (OC) is vital for the modulation of atmospheric CO2 and O2 in the Earth system, which regulates short-term climate as well as oxygenation of the early Earth. The mineral carbon pump (MnCP) was recently proposed to describe how soil minerals enhance the persistence and accumulation of OC, where interactions with minerals stabilize labile OC against microbial degradation (including via sorption, occlusion, aggregation, geopolymerization, and redox reactions).1 Given the widespread occurrence of metal (oxyhydr)oxides and clay minerals in terrestrial and marine environments and building on recent progress in mineral-OC interactions, we suggest that the MnCP occurs across the Earth system, where it plays a key role in OC preservation and hence the global carbon and oxygen cycles (Figure 1).