摘要

    在农业土壤上施用污水污泥（SS）可以帮助满足作物养分需求并增强土壤特性，同时可以再利用有机副产品。但是，SS可能是抗生素抗性基因（ARG）和移动遗传元件（MGE）的来源，导致抗生素抗性传播的风险增加。我们研究了应用热干燥厌氧消化的SS对（i）土壤理化和微生物特性，以及（ii）土壤中85个ARG和10个MGE基因的相对丰度的影响。土壤样品是从经过SS改良的各种农业领域中采集的，这三个因素不同：施药量，施药量和最后施药后经过的时间。与未经改良的土壤相比，经SS改良的土壤中ARG和MGE基因的相对丰度更高，尤其是在SS应用较新的土壤中。一些物理化学参数（即阳离子交换容量，铜浓度，磷含量）与ARG和MGE基因的相对丰度正相关。污水污泥的应用是解释ARGs和MGE基因分布模式的关键因素。土壤原核生物群落中最丰富的30个科目占ARG和MGE基因相对丰度总变异的66％。土壤原核α多样性与ARG和MGE基因的相对丰度呈负相关。我们得出的结论是，用热干燥的厌氧消化的污水污泥改良的农业土壤显示出增加的抗生素耐药性传播风险。

    The application of sewage sludge (SS) to agricultural soil can help meet crop nutrient requirements and enhance soil properties, while reusing an organic by-product. However, SS can be a source of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), resulting in an increased risk of antibiotic resistance dissemination. We studied the effect of the application of thermally-dried anaerobically-digested SS on (i) soil physicochemical and microbial properties, and (ii) the relative abundance of 85 ARGs and 10 MGE-genes in soil. Soil samples were taken from a variety of SS-amended agricultural fields differing in three factors: dose of application, dosage of application, and elapsed time after the last application. The relative abundance of both ARGs and MGE-genes was higher in SS-amended soils, compared to non-amended soils, particularly in those with a more recent SS application. Some physicochemical parameters (i.e., cation exchange capacity, copper concentration, phosphorus content) were positively correlated with the relative abundance of ARGs and MGE-genes. Sewage sludge application was the key factor to explain the distribution pattern of ARGs and MGE-genes. The 30 most abundant families within the soil prokaryotic community accounted for 66% of the total variation of ARG and MGE-gene relative abundances. Soil prokaryotic α-diversity was negatively correlated with the relative abundance of ARGs and MGE-genes. We concluded that agricultural soils amended with thermally-dried anaerobically-digested sewage sludge showed increased risk of antibiotic resistance dissemination.

     https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113772/