Field aging alters biochar's effect on antibiotic resistome in manured soil

• Published in: Environmental pollution (1987) 2021-11, Vol.288, p.117719-117719, Article 117719
• Main Authors: Cheng, Jian-Hua, Tang, Xiang-Yu, Su, Jian-Qiang, Liu, Chen
• Format: Article
• Language: English
• Subjects: Aging; Antibiotic resistome; Bacterial composition; Biochar; Soil
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2021.117719

Current understanding of biochar's effect on antibiotic resistance genes (ARGs) in soil is limited, and whether the effect could change after long-term field aging remains largely unknown. In this study, we employed high-throughput quantitative PCR to assess the effect of biochar amendment on soil resistome as affected by three years of field aging. Application of fresh biochar significantly elevated the number and abundance of ARGs in the manured soil, but did not show such effect under pakchoi cultivation. The presence of aged biochar caused a marked reduction of ARGs only in the planted manured soil. Results of principal coordinate analysis and structural equation modeling indicate that biochar's effect on soil ARG profile was changed by field aging through altering soil microbial composition. These results highlight the necessity of considering aging effect of biochar during its on-farm application to mitigate soil antibiotic resistance. [Display omitted] •Fresh biochar amendment resulted in an enrichment of ARGs in unplanted soil.•Pakchoi cultivation increased the number and relative abundance of ARGs.•Aged biochar caused a reduction of ARGs in planted soil.•Biochar aging significantly affected ARG profile by altering soil microbiome.