金属氧化物与非金属氧化物纳米颗粒暴露下人工湿地微生物群落的响应差异OA北大核心CSTPCD

The extensive application of nano-products leads to the wide distribution of nano-particles in different environments,which causes potential ecological risks.Constructed wetland is a sewage ecological treatment system composed of plants,substrates and microorganisms,which inevitably becomes the"sink"of nanoparticles.To compare the ecological effects difference of metal oxide nanoparticles and non-metal oxide nanoparticles on microbial communities in constructed wetlands.The study selected graphene oxide(GO)and copper oxide nanoparticles(CuO NPs)as the objects of the study,and constructed three groups of Iris pseudacorus-constructed wetland ecological treatment systems with vertical flow,including the control group(without nanoparticles),the GO-exposed group and the CuO NPs exposed group.The dynamic response of microbial communities in constructed wetland ecosystems exposed to GO and CuO NPs was investigated.The results of 16S rDNA sequencing showed that the richness and diversity of the microbial community increased under GO and CuO NPs exposure,while the exposure of CuO NPs suppressed the evolutionary diversity of the microbial community.As the dominant phylum,the abundance of Actinobacteria decreased when exposed exposure to pollutants,while the phylum of Proteobacteria showed better adaptability.The microbial community structure responded to different nanoparticle exposures by different mechanisms,e.g.,the class of Actinobacteria and Gammaproteobacteria was suppressed by the pollutants in the abundance,while the dominant genus of Mycobacterium was more tolerant to GO exposures and less tolerant to CuO NPs exposures.According to the classification of the KEGG database,Some metabolic pathways of constructed wetlands are weakened after pollutant exposure.It was also found that Carbohydrate metabolism and Amino acid metabolism showed lower abundance in the CuO NPs exposure treatment group.The above results suggest that CuO NPs may be more ecotoxic to constructed wetlands,and the study also provides a new perspective for nanomaterials to affect the ecological functions of constructed wetlands.