Contrasting spatial patterns of antibiotics and antibiotic resistance genes in surface sediments along the Yangtze river
- 1School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu province, 221116, China
- 2Corresponding author.
Abstract
Antibiotics and antibiotic resistance genes (ARGs) are emerging contaminants of concern in large-river sediments, yet their spatial covariation across dam-regulated river systems remains poorly understood. To address this question, surface sediments were collected along the main stem of the Yangtze River, covering the upstream reach, the Three Gorges Reservoir (TGR), the middle reach, and the downstream reach. Of the 44 target antibiotics, 35 were detected. Metagenomic analysis of 15 samples with useable sequencing datasets identified 828 putative ARG subtypes, among which 23 representative subtypes were selected for detailed spatial comparison. Tetracyclines accounted for more than 90% of the total antibiotic burden, with mean concentrations decreasing from 82.97 ng/g upstream to 70.81 ng/g in the TGR, and 49.22 ng/g downstream. In contrast, the summed abundance of the 23 selected ARGs was higher downstream (68,867 RPKM) than upstream (48,377 RPKM), demonstrating incomplete spatial concordance between antibiotic residues and the sediment resistome. Exploratory multivariate analyses indicated that ARGs variation was jointly associated with sediment properties, antibiotic residues, microbial communities, and MGEs. The PLS-PM showed positive direct path coefficients from antibiotics (β = 0.390), MGEs (β = 0.334), and sediment properties (β = 0.306) to ARGs. Pseudomonadota- and Nitrospirota-affiliated metagenome-assembled genomes were identified as potential ARGs hosts. Positive associations between ARGs and mobile genetic elements suggested elevated genetic mobility potential within the sediment resistome. Risk assessment identified tetracycline as the principal antibiotic-related ecological concern, with a maximum hazard quotient of 18.9 in the TGR, whereas the evaluated ARGs remained within the lowest potential human-health risk rank. These findings demonstrate contrasting spatial patterns of antibiotics and ARGs along the Yangtze River and identify sediment properties, microbial communities, and genetic mobility potential as important correlates of ARGs variation.
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BibTeX
@article{liang2026contrasting,
title = {{Contrasting spatial patterns of antibiotics and antibiotic resistance genes in surface sediments along the Yangtze river}},
author = {Xu Liang and Wenju Lei and Zhijie Zhang and Jiaxun Guo and Haitang Wang and Yunzhi Qian and Liping Wang and Bo Nie and Shilong He},
journal = {Emerging Contaminants},
year = {2026},
month = oct,
doi = {10.1016/j.emcon.2026.100774},
url = {https://doi.org/10.1016/j.emcon.2026.100774},
note = {CC BY},
}
RIS
TY - JOUR
TI - Contrasting spatial patterns of antibiotics and antibiotic resistance genes in surface sediments along the Yangtze river
AU - Xu Liang
AU - Wenju Lei
AU - Zhijie Zhang
AU - Jiaxun Guo
AU - Haitang Wang
AU - Yunzhi Qian
AU - Liping Wang
AU - Bo Nie
AU - Shilong He
PY - 2026
DA - 2026/10/30
JO - Emerging Contaminants
DO - 10.1016/j.emcon.2026.100774
UR - https://doi.org/10.1016/j.emcon.2026.100774
AB - Antibiotics and antibiotic resistance genes (ARGs) are emerging contaminants of concern in large-river sediments, yet their spatial covariation across dam-regulated river systems remains poorly understood. To address this question, surface sediments were collected along the main stem of the Yangtze River, covering the upstream reach, the Three Gorges Reservoir (TGR), the middle reach, and the downstream reach. Of the 44 target antibiotics, 35 were detected. Metagenomic analysis of 15 samples with useable sequencing datasets identified 828 putative ARG subtypes, among which 23 representative subtypes were selected for detailed spatial comparison. Tetracyclines accounted for more than 90% of the total antibiotic burden, with mean concentrations decreasing from 82.97 ng/g upstream to 70.81 ng/g in the TGR, and 49.22 ng/g downstream. In contrast, the summed abundance of the 23 selected ARGs was higher downstream (68,867 RPKM) than upstream (48,377 RPKM), demonstrating incomplete spatial concordance between antibiotic residues and the sediment resistome. Exploratory multivariate analyses indicated that ARGs variation was jointly associated with sediment properties, antibiotic residues, microbial communities, and MGEs. The PLS-PM showed positive direct path coefficients from antibiotics (β = 0.390), MGEs (β = 0.334), and sediment properties (β = 0.306) to ARGs. Pseudomonadota- and Nitrospirota-affiliated metagenome-assembled genomes were identified as potential ARGs hosts. Positive associations between ARGs and mobile genetic elements suggested elevated genetic mobility potential within the sediment resistome. Risk assessment identified tetracycline as the principal antibiotic-related ecological concern, with a maximum hazard quotient of 18.9 in the TGR, whereas the evaluated ARGs remained within the lowest potential human-health risk rank. These findings demonstrate contrasting spatial patterns of antibiotics and ARGs along the Yangtze River and identify sediment properties, microbial communities, and genetic mobility potential as important correlates of ARGs variation.
SN - 2405-6650
ER -