Contrasting Impacts on Carbon Mineralization Kinetics and Temperature Sensitivity: Role of Exogenous Organic Amendments in Reclaimed Mine Soils

ABSTRACT Application of soil amendments is an effective management strategy to promote the fertility of highly degraded soil. However, information about the soil carbon (C) mineralization and its temperature sensitivity ( Q 10 ) in response to organic amendment sources in mining areas is limited. To address this knowledge gap, we investigated the impact of exogenous C sources (corn stover, cattle manure, and chicken manure) and two temperature regimes (25°C and 35°C) on apparent C mineralization in a 90‐day incubation experiment. Results revealed that exogenous organic amendments induced substantially higher CO 2 fluxes during the first 15 days of incubation relative to the non‐C‐amended control, particularly in corn stover treatments. Cumulative CO 2 production was higher in chicken manure than in cattle manure within the initial few days of incubation, while this trend was reversed at the later stage of incubation. The first‐order model showed that the highest C 0 values were recorded in the corn stover applied treatment. The increased incubation temperature resulted in a greater C mineralization rate for all treatments. Exogenous C inputs reduced the Q 10 value during the 0–30 days incubation period ( p < 0.05) whereas soils with cattle manure sustained the highest Q 10 value for the entire 90 days incubation period. Furthermore, the cattle manure addition treatment maximized enzyme activities and microbial α‐diversity at 25°C, highlighting its strong stimulatory effect on soil biochemical processes. Our study suggests that C mineralization and its temperature sensitivity in mine soil are highly dependent on substrate type and exhibit significant variations throughout the incubation period.