Abstract:
Chicken manure (CM) can pose a serious threat to environmental and human health, and need to be managed properly. The compost can effectively treat CM. However, there is limited research on the heavy metals and antibiotic resistance genes (ARGs) during compost CM. In this study, the combined application of reactor and static composting (RSC) was used to produce organic fertilizer of CM (OCM), and heavy metals, ARGs and bacterial community structure was investigated. The results show that RSC could be used to produce OCM, and OCM meet the National organic fertilizer standard (NY/T525-2021). Compared to the initial CM, DTPA-Cu, DTPA-Zn, DTPA-Pb, DTPA-Cr, DTPA-Ni and DTPA-As in OCM decreased by 40.83%, 23.73%, 34.27%, 38.62%, 16.26%, and 43.35%, respectively. RSC decreased the relative abundance of ARGs in CM by 84.06%, while the relative abundance of sul1 and ermC increased. In addition, the relative abundance and diversity of ARGs were mainly influenced by the bacterial community, with Actinobacteria, Firmicutes, and Proteobacteria becoming the dominant phyla during composting, and probably being the main carriers and dispersers of most of the ARGs. Network analyses confirmed that Gracilibacillus, Lactobacillus, Nocardiopsis, Mesorhizobium and Salinicoccus were the main potential hosts of ARGs, with the main potential hosts of sul1 and ermC being Mesorhizobium and Salinicoccus. The passivation and physicochemical properties of heavy metals contribute to the removal of ARGs, with sul1 and ermC being affected by the toal heavy metals. Application of RSC allows CM to produce mature, safe organic fertilizer after 32 d and reduces the risk of rebound from ARGs, but the issues of sul1 and ermC gene removal cannot be ignored.
摘要:
鸡粪会对环境和人类健康造成严重威胁,需要妥善管理。堆肥可以有效地处理CM。然而,关于堆肥过程中重金属和抗生素抗性基因(ARGs)的研究有限。在这项研究中,反应器和静态堆肥(RSC)的联合应用用于生产CM(OCM)有机肥料,和重金属,研究了ARGs和细菌群落结构。结果表明,RSC可用于生产OCM,OCM符合国家有机肥标准(NY/T525-2021)。与最初的CM相比,DTPA-Cu,DTPA-Zn,DTPA-Pb,DTPA-Cr,OCM中DTPA-Ni和DTPA-As下降40.83%,23.73%,34.27%,38.62%,16.26%,和43.35%,分别。RSC使CM中ARGs的相对丰度降低了84.06%,而sul1和ermC的相对丰度增加。此外,ARGs的相对丰度和多样性主要受细菌群落的影响,放线菌,Firmicutes,和变形杆菌成为堆肥过程中的优势门,可能是大多数ARGs的主要携带者和传播者。网络分析证实了芽孢杆菌,乳酸菌,诺卡氏菌病,中根瘤菌和盐生菌是ARGs的主要潜在宿主,sul1和ermC的主要潜在宿主是中根瘤菌和盐藻。重金属的钝化和物理化学性质有助于去除ARGs,sul1和ermC受到重金属的影响。RSC的应用允许CM生产成熟,32天后安全的有机肥,降低了ARGs反弹的风险,但sul1和ermC基因去除的问题不容忽视。