The performance of pelletized biochar on the transport of extracellular antibiotic resistance genes in marine aquaculture sediments

The transport of extracellular antibiotic resistance genes (eARGs) in intensive marine aquaculture has become a serious threat to global environmental ecological security and public health within the framework of "One Health". However, the inhibitory effect and mechanism of pelletized biochars (PBCs) on the migration of eARGs in aquaculture sediments remain unclear. This study investigated the inhibitory efficiency of PBCs on the transport of eARGs in marine aquaculture sediments and discussed the influence of salinity changes on the transport performance of eARGs. The results showed that PBCs could effectively inhibit the transport of eARGs, and the order of inhibitory effect was PBC700 > PBC300 > CK. This mechanism mainly relies on the fact that pelletized biochar primarily increases the surface roughness of porous media to provide more adsorption sites, and in combination with π-π interactions and electrostatic forces, significantly inhibits the migration of eARGs. When salinity increased, the inhibitory effect of PBCs on eARGs was enhanced. This study provided theoretical support for the development of functional materials based on pelletized biochars to control the transport of eARGs in marine aquaculture sediments.