College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
Environ Int. 2021 Nov;156:106620. doi: 10.1016/j.envint.2021.106620. Epub 2021 May 11.
Agricultural soil is highly susceptible to manure contamination and thus is a potential source for the spread of pathogens and antibiotic resistance genes (ARGs). Routine monitoring fecal contamination in agricultural soil can reduce the manure-derived ARG contaminations. This study investigated the distribution of crAssphage, a highly human-specific indicator of fecal pollution, in agricultural soils in the Yangtze River Delta (YRD) of China, and its potential in serving as an indicator of soil ARGs. CrAssphage was indeed strongly correlated with the abundance of soil ARGs, and particularly tetracycline resistance gene tetW (rho = 0.55, p < 0.01). Meanwhile, with the increasing of crAssphage abundance, the frequency of multiple abundant ARGs is also increased. When the relative abundance of crAssphage in soil samples exceeded 4.94 × 10 copies per copy of the 16S rRNA gene, there would be more than three types of co-existing ARGs. Regional differences in crAssphage and ARGs abundances were observed for samples collected from Zhejiang, Shanghai, Jiangsu, and Anhui in the YRD, indicating different levels of fecal pollution therein. High sewage treatment capacity could contribute to the reduce of fecal pollution and the control ARG transmission in agricultural soils.
农业土壤极易受到粪便污染，因此是病原体和抗生素耐药基因（ARGs）传播的潜在来源。常规监测农业土壤中的粪便污染可以减少粪源 ARG 污染。本研究调查了在中国长江三角洲（YRD）农业土壤中高度特定于人类的粪便污染指示物 crAssphage 的分布及其作为土壤 ARGs 指示物的潜力。 crAssphage 确实与土壤 ARGs 的丰度密切相关，特别是与四环素耐药基因 tetW（rho = 0.55，p < 0.01）。同时，随着 crAssphage 丰度的增加，多种丰富的 ARGs 的频率也会增加。当土壤样品中 crAssphage 的相对丰度超过 16S rRNA 基因拷贝数的 4.94×10 时，会有超过三种共存的 ARGs。从 YRD 的浙江、上海、江苏和安徽采集的样本中观察到 crAssphage 和 ARGs 丰度的区域差异，表明其中存在不同程度的粪便污染。高污水处理能力有助于减少农业土壤中的粪便污染和控制 ARG 传播。
