Enhancement by <i>Burkholderia contaminans</i> ZCC Combined with Biochar on the Remediation of Arsenic-Contaminated Soil by <i>Pteris vittata</i>.

Abstract

Arsenic pollution is a global environmental challenge, necessitating efficient and sustainable remediation technologies. This study investigates the synergistic effect of the arsenic-resistant bacterium <i>Burkholderia contaminans</i> ZCC (ZCC) and corn stalk biochar (BC) on arsenic-contaminated soil, with <i>Pteris vittata</i> as the remediation plant. Through pot experiments, we evaluated the effects of various BC addition rates (0%, 1%, 5%) and ZCC inoculation on soil pH, plant growth, physiological responses, and arsenic accumulation. Biochar alone significantly increased soil pH (reaching 7.56 in the 5% BC treatment), while <i>B. contaminans</i> ZCC alone had a weaker effect. In combined treatments, pH changes were primarily driven by biochar. The combination of <i>B. contaminans</i> ZCC and BC enhanced <i>P. vittata</i> growth, with the 5% BC + ZCC treatment showing the greatest increase in total plant biomass (2.56 times that of the control) and total chlorophyll content (43.32% higher). This treatment also activated antioxidant systems (increased SOD, POD, and CAT activities), reduced oxidative damage (lower MDA content), and improved osmotic regulation (higher proline content). Notably, <i>B. contaminans</i> ZCC and BC synergistically enhanced arsenic accumulation in the <i>P. vittata</i> plant, with the arsenic content under the 5% BC + ZCC treatment being 2.81 times that of the control. This study demonstrates that the combination of <i>B. contaminans</i> ZCC and BC enhances arsenic remediation through soil improvement and plant growth promotion.