Dataset for Disentangling the roles of microbial traits and mineral protection in regulating temperature sensitivity of soil carbon decomposition in eroded and depositional agricultural soils

The temperature sensitivity of soil organic carbon decomposition (Q10) governs the fate of soil carbon under global warming. Although water erosion redistributes soil carbon on a scale comparable to that of the terrestrial carbon sink, how erosion reshapes the spatial patterns of Q10 across large regional scales remains elusive due to complex regulatory mechanisms. Here, we quantified erosion-induced changes in Q10 across three major erosion-prone regions in China. We found that, relative to non-eroded controls, erosion increased Q10 by 4.3% in eroded zones but decreased Q10 by 12.7% in depositional zones. In depositional zones, Q10 was jointly regulated by carbon quality and mineral–aggregate protection, whereas in eroded zones, reduced mineral protection shifted the dominant controls to carbon quality and microbial traits. Intensified erosion reduced organic carbon quality, mineral–aggregate protection, and soil C:N ratios, thereby promoting higher bacterial-to-fungal ratios and phenol oxidase activity, which ultimately enhanced Q10. Model projections further indicated that, by 2100, carbon emissions from eroded soils would exceed those from depositional soils by 17.3% and 38.1% under the SSP2–4.5 and SSP5–8.5 scenarios, respectively. These findings highlight the necessity of restoring eroded landscapes for climate mitigation and integrating erosion–carbon feedbacks into Earth system models to improve global carbon predictions.