Yan Chunni, Huang Juan, Lin Xiaoyang, Wang Yaoyao, Cao Chong, Qian Xiuwen
Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 211189, China.
Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 211189, China.
J Environ Manage. 2023 May 15;334:117432. doi: 10.1016/j.jenvman.2023.117432. Epub 2023 Feb 8.
Constructed wetlands (CWs) have been expected advantages in emerging pollutant removal, but with less known on their characteristic when treating wastewater containing graphene oxide (GO). In present study, we investigated characteristics of Iris pseudacorus, microorganisms, and pollutant removal in CWs with 60 cm and 37 cm water level (termed HCW and LCW). Plants in LCW had higher chlorophyll content and lower activities of antioxidant enzyme (superoxide dismutase, catalase, peroxidase) as well as malondialdehyde content. Substrate enzyme activities were affected by time and CW type. LCW increased only dehydrogenase activities, while HCW increased catalase, urease, neutral phosphatase, and arylsulfatase activities. Sequencing analysis revealed that microbial community showed higher richness and diversity in LCW, but this dissimilarity could be eased by time-effect. Proteobacteria (25.62-60.36%) and Actinobacteria (13.86-56.20%) were stable dominant phyla in CWs. Ratio of Proteobacteria/Acidobacteria indicated that trophic status of plant rhizosphere zone was lower in LCW. Nitrospirae were enriched to 0.16-0.68% and 0.75-1.42% in HCW and LCW. The enrichment of phyla Proteobacteria and Firmicutes in HCW was attributed to class Gammaproteobacteria and genus Enterococcus. GO transformation showed some reductions in CWs, which could be affected by water depth and substrate depth. Overall, HCW achieved nitrogen and phosphorus removal for 48.78-62.99% and 95.01%, which decreased by 8.41% and 7.31% in LCW. COD removal was less affected reaching 93%. This study could provide some new evidence for CWs to treat wastewater containing GO.
人工湿地（CWs）在去除新兴污染物方面具有预期优势，但在处理含氧化石墨烯（GO）废水时其特性鲜为人知。在本研究中，我们调查了水位分别为60厘米和37厘米的人工湿地（分别称为HCW和LCW）中黄菖蒲、微生物的特性以及污染物去除情况。LCW中的植物叶绿素含量较高，抗氧化酶（超氧化物歧化酶、过氧化氢酶、过氧化物酶）活性和丙二醛含量较低。底物酶活性受时间和人工湿地类型的影响。LCW仅增加了脱氢酶活性，而HCW增加了过氧化氢酶、脲酶、中性磷酸酶和芳基硫酸酯酶活性。测序分析表明，微生物群落的丰富度和多样性在LCW中较高，但这种差异可随时间效应而缓解。变形菌门（25.62 - 60.36%）和放线菌门（13.86 - 56.20%）是人工湿地中稳定的优势菌门。变形菌门/酸杆菌门的比例表明，LCW中植物根际区的营养状况较低。硝化螺旋菌在HCW和LCW中的富集率分别为0.16 - 0.68%和0.75 - 1.42%。HCW中变形菌门和厚壁菌门的富集归因于γ-变形菌纲和肠球菌属。人工湿地中GO的转化有所降低，这可能受水深和底物深度的影响。总体而言，HCW对氮和磷的去除率分别为48.78 - 62.99%和95.01%，在LCW中分别下降了8.41%和7.31%。化学需氧量的去除受影响较小，达到93%。本研究可为人工湿地处理含GO废水提供一些新的证据。
