Combination of Biochar and Phosphorus Solubilizing Bacteria to Improve the Stable Form of Toxic Metal Minerals and Microbial Abundance in Lead/Cadmium-Contaminated Soil

Biochar adsorption and microbial remediation have great potential in the field of soil remediation, but since both are stressed by high concentrations toxic heavy metals when applied alone, combining two may become an effective method. In this study, application effect phosphorus-solubilizing bacteria (PSB) combined with rice husk biochar on Pb/Cd-mixed pollution form differences metal were studied qualitatively quantitatively. Compared contaminated soil, PSB significantly increased pH, carbon phosphorus 9.0%, 299.4% 157.0%. Meanwhile, total microbial, bacterial fungal biomass 92.11%, 103.13% 138.10%. This confirmed that addition nutrients provided good conditions for or native microorganisms to flourish. The extraction results showed stable Pb/Cd + was better than biochar/PSB alone. Combined acid-soluble non-bioavailable fraction 5/15 times 14/5.8 soil. fractions main after (>80%). mainly carbonates phosphate-based minerals (XRD analysis). PCA a GWB model further release pH key passivation short time. combination (phosphorus supply guarantee) (acid-soluble function) can reduce acidification improve nutrients, thus increasing abundance even more non-contaminated