A novel method for rapidly improving quality and carbon sequestration potential of plough layer damaged soil

PurposeStripping topsoil and transplanting seedlings damage the plough layer, reduce soil quality, and hinder food production. It is therefore urgent to rapidly improve the fertility of such plough layer damaged soils; however, there is a lack of available materials, quality evaluation methods, and application techniques.Materials and methodsUsing moss peat (M), rice husk biochar (R), sawdust biochar (S), vegetable corn husk (C), and microbial inoculants as raw materials, a novel carbon-rich soil improvement materials (CRSIM) were created.Results and discussionThe results showed that when M and R are mixed at mass ratios of 1:1, 2:1, and 3:1, M and S are mixed at a mass ratio of 3:1, mixing with C at a mass ratio of 10:1, and adding microbial inoculant Bacillus subtilis, the high-quality CRSIM can be formed ((M + R)10C1, (2 M + R)10C1, (3 M + R)10C1, and (3 M + S)10C1)), which showed loose texture, high organic matter, and stability. Adding the above four CRSIM to plough layer damaged soil at the ratio of 1 to 8% can significantly reduce the soil bulk density, increase SOC and MBC content and carbon cycling enzyme activity, and change SOC chemical composition. Among them, the most beneficial material was (3 M + R)10C1, which increased wheat yield 5.6 times compared to CK when applied to the soil. In addition, CRSIM significantly influenced bacterial community composition and diversity more than fungi. They had greater strength in microbial carbon sequestration strategies while reducing soil microbial respiration intensity and qCO2, suggesting that these CRSIM favor the development of microbiota that contributes to soil C storage.ConclusionsIn summary, mixing peat and biochar can create a novel CRSIM for plough layer damaged soil, which can improve soil quality and increase soil carbon sequestration.