研究报告
隗岚琳,刘东升,廖雪珂,陈宇琛,严晗璐,陈求稳.垂直潜流人工湿地低温净化效果及其与微生物作用关系[J].环境科学学报,2021,41(10):4039-4048
垂直潜流人工湿地低温净化效果及其与微生物作用关系
- Low temperature purification performance and the microbial activity in the vertical subsurface flow constructed wetland
- 基金项目:国家水体污染控制与治理科技重大专项(No.2017zx07603-004,2017zx07603-005)
- 隗岚琳
- 南京水利科学研究院生态环境研究所, 南京 210029
- 刘东升
- 南京水利科学研究院生态环境研究所, 南京 210029
- 廖雪珂
- 1. 南京水利科学研究院生态环境研究所, 南京 210029;2. 重庆交通大学河海学院, 重庆 400074
- 陈宇琛
- 南京水利科学研究院生态环境研究所, 南京 210029
- 严晗璐
- 南京水利科学研究院生态环境研究所, 南京 210029
- 陈求稳
- 南京水利科学研究院生态环境研究所, 南京 210029
- 摘要:人工湿地净化过程受基质、微生物及植物的多重作用,但有关湿地系统水质净化效果与微生物之间的关联及响应机制的认识较为匮乏.本文针对垂直潜流人工湿地,分析了其低温条件下水质净化效果,通过16S rDNA扩增子测序技术,在OTU水平上利用微生物丰度聚类热图和基于Bray-Curtis距离的NMDS分析,揭示了湿地基质微生物群落结构的时空变化及其与主要水质指标之间的相互作用关系.结果表明,湿地对TN、COD的去除效果较好,但对TP的去除效果不佳.基质微生物群落时空变化显著,与湿地净化效果密切相关,革兰氏阴性菌门类众多和假单胞菌属相对丰度较低,分别是TN去除效果较好和TP去除效果不佳的重要原因.COD、DO是影响微生物群落的主要因子,而氮含量在一定程度上影响脱氮微生物的活跃度.基质微生物在湿地运行2周后,对污染物去除的介导作用稳定,建议设立这一关键时间点,并辅以菌群、碳源投入等措施,提升湿地的净化效果.
- Abstract:Constructed wetland purification is influenced by substrate, microorganisms, and plants. The knowledge of the relationship between the water purification performance of a wetland system and the microbial mechanism is limited. We used a vertical subsurface flow constructed wetland to analyze the water purification under low temperature conditions. Species abundance clustering heat map and Non-metric Multidimensional Scaling (NMDS, Bray-Curtis distance) were used to reveal the temporal and spatial variations of microbial community structure in the constructed wetland and to preliminarily analyze its relationship with the main water quality indexes based on 16S rDNA Amplicon Sequencing. The treatment effect of TN and COD on the vertical subsurface flow constructed wetland were good, whereas that of phosphorus was poor. The microbial community structure showed remarkable changes with time and space in the substance. The large number of Gram-negative phyla and the relatively low number of Pseudomonas were the reasons for the improved TN and the less effective TP removal, respectively. COD and DO are the key impacting indicators for the variation of microbial community. Nitrogen content affected the activity of microorganisms to a certain extent. Indigenous microorganisms had a stable mediating effect on pollutant removal after 2 weeks of operations in the wetlands. Considering critical time point and taking measures, such as microflora and carbon source input, to optimize and improve the purification of the wetland are recommended.