Unveiling changes of microbial community involved in N and P removal in constructed wetlands with exposing to silver nanoparticles
Unveiling changes of microbial community involved in N and P removal in constructed wetlands with exposing to silver nanoparticles
复制标题
DOI：
10.1016/j.jhazmat.2022.128642
复制
发表时间：
2022-03-11
影响因子：
13.6
通讯作者：
Yan, Chun-Ni
中科院分区：
文献类型：
--
作者：
Cao, Chong;Huang, Juan;Yan, Chun-Ni
人工湿地是一种环境友好的污水净化工程系统，具有成本低、维护方便等优点。然而，目前尚不清楚功能微生物对银纳米颗粒（Ag NPs）的氮（N）和磷（P）生物转化的响应。采用高通量测序技术研究了垂直流地下连续水系统中微生物群落的变化，并稳定运行了120天。结果表明，纳米银对土壤NH 4 +-N、TN和TP的去除率分别下降了43.56%、15.7%和22.7%。微生物丰富度指数和组成的影响，和对照湿地丰富Sulfurophyllum，Desulfraculaceae和黄杆菌，而暴露于银纳米颗粒的CWs丰富Desulfosporosinus和Desulfurispora从LEfSe分析。此外，施用银纳米颗粒后，上层土壤硝化功能基因amoA和hao、反硝化功能基因nirK和norB以及磷转化功能基因ppx和phoA/phoD的相对丰度显著下调。银纳米颗粒对功能菌和基因的抑制作用是造成CWs对氮磷污染物去除效果不佳的原因。我们的研究结果提供了一个深入了解的生态毒性银纳米粒子上的CW与N和P的生物转化，并提供了理解的响应硝化细菌，藻类和PAO。
Constructed wetlands (CWs) are environmentally friendly engineered systems to purify wastewater, with lowcost and easy maintenance. However, it is not clear on responses of functional microbes for nitrogen (N) and phosphorus (P) biotransformation in CWs to silver nanoparticles (Ag NPs). The high throughput sequencings were employed to reveal microbial communities in vertical flow subsurface CWs with stable operation for 120 days. The results indicated that NH4+-N, TN and TP removal of soil layer decreased by 43.56%, 15.7% and 22.7% under stress of Ag NPs. Microbial richness index and compositions were affected, and control wetland enriched Sulfurospirillum, Desulfarculaceae and Flavobacterium whereas CWs exposed to Ag NPs enriched Desulfosporosinus and Desulfurispora from LEfSe analysis. Moreover, after dosing Ag NPs, relative abundances of functional genes amoA and hao for nitrification, nirK and norB for denitrification and ppx and phoA/phoD for phosphorus conversions in upper soil were significantly downregulated. Inhibition on functional bacteria and genes of Ag NPs explained poor removal efficiencies of nitrogen and phosphorus pollutants in CWs. Our findings give an insight into ecological toxicity of Ag NPs on CWs with N and P bioconversions and provide the understanding of response of nitrifiers, denitrifies and PAOs.