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Graphical abstract Highlights • Ag/Bi 4 O 7 /g-C 3 N 4 ternary metal/non-metal Z-scheme heterojunction was prepared. • A photodeposition experiment confirmed Z-scheme heterojunction in Ag/Bi 4 O 7 /g-C 3 N 4. • Ag adhered to g-C 3 N 4 nanosheets, constructing plasmonic metal/semiconductor system. • The visible-light photoreduction of aqueous Cr(VI) is enhanced. • The ternary Ag/Bi 4 O 7 /g-C 3 N 4 nanosheets have favorable cycling stability. Abstract In this paper, we successfully constructed a ternary metal/non-metal nanomaterial which can synergize Z-scheme heterojunction and plasmonic metal/semiconductor for enhancing visible light photoreduction of aqueous Cr(VI). The as-formed ternary metal/non-metal nanomaterial was composed of g-C 3 N 4 nanosheets mutual modified by Ag nanoparticles and Bi 4 O 7. In the ternary nanomaterial, g-C 3 N 4 nanosheets and Bi 4 O 7 fabricated Z-scheme heterojunction, g-C 3 N 4 nanosheets and Ag nanoparticles formed plasmonic metal/semiconductor system, synchronously. The photodeposition experiments were designed to indirect demonstrate the Z-scheme heterojunction via photocatalytic oxidation and reduction deposition reactions, AgNO 3 was used as the electron acceptor and Pb(NO 3) 2 as the electron donor, photocatalytic reduction product and oxidation product were selectively deposited on g-C 3 N 4 nanosheets and Bi 4 O 7 , respectively, revealing the Z-scheme heterojunction was definite formed. In addition, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), UV–vis absorption, and Fourier-transform infrared spectroscopy (FTIR) were studied to indicate that the plasmonic metal/semiconductor system was existent in the ternary nanomaterial. The visible light photoreduction of ternary Ag/Bi 4 O 7 /g-C 3 N 4 nanosheets was evaluated by photoreducing aqueous Cr(VI). The photoreduction results show that the ternary Ag/Bi 4 O 7 /g-C 3 N 4 nanosheets is much higher than the pristine bulk g-C 3 N 4 and g-C 3 N 4 nanosheets. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Biochar impeded the vertical migration of ARPB from top soil to lower soil. • Polyvalent phage targeted inactivation of ARPB along different soil layers. • Biochar amendment with phage therapy synergistically eliminated ARG risk. • Combined treatment maintained the diversity of the bacteria community. Abstract The vertical migration of antibiotic resistance pathogenic bacteria (ARPB) and antibiotic resistance genes (ARGs) in the surface soil-vadose soil system has become a new threat to ecological safety and public health; there is an imperative need to develop an efficient technique for targeted control and inactivation of ARPB in these systems. In this work, undisturbed soil columns (0 ∼ −5 m) were constructed to investigate the impact of biochar amendment or/and polyvalent bacteriophage (ΦYSZ-KK) therapy on the vertical control and inactivation of tetracycline-resistant Escherichia coli K-12 and chloramphenicol-resistant Klebsiella pneumonia K-6. The simultaneous application of polyvalent phage and biochar impeded the vertical migration of ARPB from the top soil to lower soil layers and stimulated the ARPB dissipation in the soil column. After 60-day incubation, levels of ARPB and ARGs decreased significantly in the soil column by magnitudes of 2-6. Additionally, high throughput sequencing indicated that the simultaneous application of biochar and phage clearly maintained the structure and diversity of the soil microbial communities (p < 0.05). This work therefore demonstrates that the application of a biochar/phage combination is an environmentally friendly, efficacious measure for the control and inactivation of ARPB/ARGs in vertical soil column systems. [ABSTRACT FROM AUTHOR]

The emerging mixed contamination of antibiotics and microplastics in greenhouse soil has made the control of antibiotic resistant gene (ARG) transmission a novel challenge. In this work, surfactant sophorolipid was applied to enhance the dissipation of tetracycline (TC) and tet genes in the presence of microplastics in greenhouse soil. During 49 days of incubation, soil bacteria and phages were both found to be the crucial reservoirs of ARGs. Meanwhile, microplastic’s presence significantly inhibited the dissipation of TC and ARGs in the soil. However, sophorolipid application was proved to outweigh the negative impact caused by microplastic existence, and lead to the highest dissipation of soil TC and ARGs. Significant positive correlation was detected between the dissipation rate of water-soluble and exchangeable TC content and bacteria/phage co-mediated ARG levels. This also held true between the two fractions of soil TC and the ratio of ARG level in the bacteria to that in the phages (B ARGs /P ARGs ). The opposite impacts of microplastic presence and sophorolipid amendment on the TC/ARG dissipation found in this work provides new information for understanding ARG transmission between bacteria and phages in the mixed contaminated greenhouse soil. [ABSTRACT FROM AUTHOR]