Effective and sustainable management of low-fertility reclaimed soils via reed-based carbon amendments is crucial for environmental nutrient cycling, yet their effects on soil microenvironments and microbial function warrant further exploration. A 60-day incubation experiment evaluated four amendments (reed straw-RS; biochar-RB; biochar-conditioned compost RC1; sediment-biochar co-conditioned compost RC2) at 0%, 5%, 10%, 15% rates on soil properties, organic carbon (C) mineralization, and microbial structure. Results showed that the exogenous carbon addition significantly altered soil physicochemical properties, initially elevating TOC and TN stocks. Following a 60-day incubation, the RC2 treatment exhibited the most pronounced TOC depletion (23.8%, p C0) differed significantly (p Actinobacteriota and Proteobacteria by 26.1% and 4.98%, respectively. Redundancy analysis linked microbial variations to compost treatments, and Cluster of Orthologous Groups (COG) analysis revealed high sensitivity of amino acid transport and metabolism to exogenous C. In conclusion, reed-based amendments improved soil properties and enzyme activities; RS showed a stronger priming effect on C mineralization than RB and composts, with 10% RC2 emerging as a promising amendment.
Liu et al. (Fri,) studied this question.