The Remediation Effects of Different Biofertilizers on Bacterial Community in Hg-Contaminated Soil

Abstract

ABSTRACT Guizhou province is the most abundant region of mercury resources in China. The long history of mining activities has resulted in severe mercury (Hg) pollution and endangering both environment and human health. This study investigated the impact of different fertilizers on Hg-polluted soil bacterial community structure. We assumed that (1) fertilizer application would lead to changes in the bacterial community; and (2) the combined application of two fertilizers did not cause additive effects. The results revealed the application of bio-organic fertilizer could significantly enhance the bacterial community diversity. However, the combination of multiple fertilizers did not yield synergistic effects. There were indications of antagonistic interactions between certain fertilizers via competition or inhibitory effects. Additionally, we conducted an experiment in the greenhouse with Brassica Pekinensis and the Hg contents in roots and leaves were measured. Our findings suggested that different fertilizers would change the release fluxes of soil Hg(0). By immobilization of Hg in the soil, fertilizer could promote a healthier and more diverse soil bacterial community. This study provides valuable insights into the influence of different fertilizers on bacterial community in Hg-polluted soil, offering potential directions for further remediation efforts and policies.