摘要

硝酸盐和抗生素/抗生素抗性基因（ARG）的混合污染对农田土壤而言是新出现的环境风险。 这是首次研究过量人为硝酸盐投入在土壤抗生素/ ARGs缺氧耗散中的作用。 在最初10天的培养期间，土壤抗生素的存在显着抑制了土壤中NO3-耗散，N2O产生速率和反硝化基因（DNG）丰度（p <0.05）。相比之下，在第10天和第30天之间，增强的反硝化作用明显促使抗生素含量和ARG丰度下降。在DNG和ARG之间检测到显着负相关，表明DNG活性越高，反硝化作用越显着，抗生素消散和ARG丰度越大。本研究为理解土壤DNG和ARG在增强缺氧反硝化条件下的相互作用提供了重要的知识。

Mixed contamination of nitrate and antibiotics/antibiotic-resistant genes (ARGs) is an emerging environmental risk to farmland soil. This is the first study to explore the role of excessive anthropogenic nitrate input in the anoxic dissipation of soil antibiotic/ARGs. During the initial 10 days of incubation, the presence of soil antibiotics significantly inhibited NO3−dissipation, N2O production rate, and denitrifying genes (DNGs) abundance in soil (p < 0.05). Between days 10 and 30, by contrast, enhanced denitrification clearly prompted the decline in antibiotic contents and ARG abundance. Significantly negative correlations were detected between DNGs and ARGs, suggesting that the higher the DNG activity, the more dramatic is the denitrification and the greater are the antibiotic dissipation and ARG abundance. This study provides crucial knowledge for understanding the mutual interaction between soil DNGs and ARGs in the enhanced anoxic denitrification condition.

https://www.sciencedirect.com/science/article/pii/S0269749116316463