Localized intensification of arsenic methylation within landfill leachate-saturated zone.
Sci Total Environ
; 842: 156979, 2022 Oct 10.
Article
en En
| MEDLINE
| ID: mdl-35764148
ABSTRACT
Leachate-saturated zone (LSZ) of landfills is a complicated biogeochemical hotspot due to the continuous input of electron donors and acceptors from the top refuse layer with leachate migration. In this study, the methylation behavior of the arsenic (As) was investigated. The results indicate that As-methylation processes are influenced by temperature fields in LSZ. The dimethylarsinic acid biotransformation capability can be enhanced with an increase in temperature. Microbial diversity, quantification of functional gene (arsM), and co-occurrence network analysis further characterized the drivers of As methylation in LSZ. As-biogeochemical cycle pathways, as well as As-functional gene distribution among different temperature fields, were modeled on the basis of KEGG annotation. Binning analysis was further employed to assemble As-methylated metagenomes, enabling the identification of novel species for As methylation in landfills. Then, 87 high-quality draft metagenome-assembled genomes (MAGs) were reconstructed from LSZ refuse samples; nearly 15 % (13 of 87) belonged to putative As-methylates functional MAGs. Combined with the model of the As-biogeochemical cycle, nine putative functional species could complete methylation processes alone. The findings of this study highlighted the temperature influence on the As-methylation behavior in LSZ and could facilitate the management of As contamination in landfills.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Arsénico
/
Contaminantes Químicos del Agua
/
Eliminación de Residuos
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Sci Total Environ
Año:
2022
Tipo del documento:
Article
País de afiliación:
China