College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China; Institute of New Rural Development of Guizhou University, Guiyang, 550025, China.
College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
Chemosphere. 2022 Aug;301:134761. doi: 10.1016/j.chemosphere.2022.134761. Epub 2022 Apr 28.
Constructed wetlands (CWs) can effectively treat landfill leachate (LL). However, there is limited research on the removal of organochlorine pesticides (OCPs) refractory organics during LL treatment in CWs. In this study, multi-stage subsurface flow CWs was used to treat LL, and the removal fate of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in CWs was investigated. The structural differences between plant roots and substrate microbial communities were compared and the Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway of organic matter was analyzed based on metagenomic analysis. The results showed that substrate adsorption (50.55%-72.74%) and microbial degradation (20.38%-27.89%) were the main ways to remove OCPs. The Proteobacteria occupied a dominant position in the CWs system, among which Betaproteobacteria (34.37%-35.90%) were contained in the substrate, and Alphaproteobacteria (21.19%-23.84%) was a more dominant microorganism in plant roots. Formaldehyde assimilation and serine pathway were the main pathways of methane metabolism. This study provides a reference for the removal mechanism of OCPs to promote the application of CWs technology in LL treatment.
人工湿地（CWs）可以有效处理垃圾渗滤液（LL）。然而，关于 CWs 处理 LL 过程中去除有机氯农药（OCPs）难降解有机物的研究还很有限。本研究采用多级潜流 CWs 处理 LL，考察了 CWs 中六六六（HCH）和滴滴涕（DDT）的去除情况。比较了植物根系和基质微生物群落的结构差异，并基于宏基因组分析分析了有机物的京都基因与基因组百科全书（KEGG）代谢途径。结果表明，基质吸附（50.55%-72.74%）和微生物降解（20.38%-27.89%）是去除 OCPs 的主要方式。CWs 系统中占优势地位的是变形菌门，其中β变形菌门（34.37%-35.90%）存在于基质中，而α变形菌门（21.19%-23.84%）是植物根系中更占优势的微生物。甲醛同化和丝氨酸途径是甲烷代谢的主要途径。本研究为 OCPs 的去除机制提供了参考，以促进 CWs 技术在 LL 处理中的应用。
