摘要
      秸秆掺入再生土壤已被证明可以增加土壤养分，并有可能有效提高作物产量。然而，哪种掺入模式更有助于控制抗生素抗性基因（ARGs）仍然未知。在本研究中，我们系统地比较了用稻草（RS）和转化产物、生物炭（RSB）和灰烬（RSA）改良的诺氟沙星污染土壤中抗生素耐药性的发生情况。RS显著促进了诺氟沙星的降解（0.0648 d−1，比对照快3倍），而RSB几乎没有作用，RSA阻碍了降解。基于宏基因组分析，RS和RSB在土壤培养结束时显著降低了ARGs的相对丰度（0.1421和0.1991，而对照组为0.2540）。Adonis试验表明，所有改良处理都能显著影响土壤中的微生物群落，而只有RS和RSB能显著影响抗生素耐药性的变化。Procrustes分析证实了微生物群落和ARGs之间的联系。网络分析进一步表明，放线菌的减少是土壤掺入过程中ARGs相对丰度普遍下降的主要原因，而变形菌和拟杆菌在早期阶段负责RS和RSB中ARG的暂时促进。最后，建议科学设置稻草的使用方法，优化生物炭的制备工艺，以同步控制土壤掺入过程中抗生素和ARGs的风险。
Abstract
Straw incorporation into reclaimed soils has been demonstrated to increase soil nutrients and has the potential to efficiently increase crop production. However, which incorporation mode is more helpful in the control of antibiotic resistance genes (ARGs) remains unknown. In this study, we systematically compared the occurrence of antibiotic resistome in norfloxacin contaminated soils amended with rice straw (RS) and the transformation products, biochar (RSB) and ash (RSA). RS significantly promoted the degradation of norfloxacin (0.0648 d−1, 3 times faster than control), whereas RSB had little effect and RSA hindered the degradation. Based on metagenomic analysis, RS and RSB significantly reduced the ARGs relative abundance (0.1421 and 0.1991 compared to 0.2540 in control) at the end of soil incubation. Adonis test indicated that all of amendment treatments significantly affect the microbial communities in soils, whereas only RS and RSB significantly affect the variation of antibiotic resistome. Procrustes analysis confirmed the association of microbial communities and ARGs. Network analysis further revealed that the reduction in Actinobacteria was the main reason for the general decrease of ARGs relative abundance during soil incorporation, whereas Proteobacteria and Bacteroidetes were responsible for temporary promotion of ARGs in RS and RSB at the early stage. Finally, scientifically setting up the usage of rice straw and optimizing the preparation process of biochar are suggested for the synchronous control of the risk of antibiotics and ARGs during soil incorporation.

https://www.sciencedirect.com/science/article/abs/pii/S0045653522039443