Remediation of Arsenic-contaminated Soil in Northwestern China by Pseudomonas Taiwanensis

Abstract The physiological resistance of Pseudomonas taiwanensis to heavy metals was studied and used to repair heavy metal contaminated water and soil. The results showed that the suitable pH conditions for the growth of P. taiwanensis were 5-9, and the salt tolerance was 6%. The tolerance concentrations for heavy metals As(V) and Mn(II) were 500 mg L-1 and 120 mg L-1, respectively. The strains were enriched by nutrient broth(NB) medium. After logarithmic phase, the bacteria liquid was mixed with ATCCTM#279 medium in proportion, and a certain amount of Mn(II) was added. The results of removing heavy metals As, Pb and Cd in the composite polluted water phase were 22.09%, 30.75% and 35.33%. The molar ratio of manganese and iron will affect the removal efficiency of single pollution heavy arsenic. When the ratio of iron and manganese is 1:5, the highest removal efficiency is 68%. However, when the remediation method is added to the soil, it cannot fix all metals, such as Cu and Zn. This remediation method provides a reference for the practical engineering application of microbial remediation.