Adsorption and degradation of chlorinated alkanes in landfill cover soil:insights into soil microecology and metabolic dynamics
The vegetation community composition of a landfill in Chongqing was comprehensively investigated for three consecutive years.The results indicated significant differences in the adsorption of chlorinated alkanes by rhizosphere soils from different vegetation.The adsorption amounts of DCM,CF,and CT in the rhizosphere soils were 1.0～5.14mg/gsoil,0.7～3.1 mg/gsoil,and 0.32～3.3mg/gsoil,respectively,with the maximum adsorption being more than three times that of bare soil.Among the vegetation,Rumex and Cynodon dactylon exhibited the highest adsorption of DCM,while Limonium sinuatum and Miscanthus floridulus had the strongest adsorption of CF.The adsorption of chlorinated alkanes by most vegetation rhizosphere soils conformed to the Freundlich model.The results of the biodegradation experiment showed that rhizosphere soils significantly enhanced the biotransformation of CH4,DCE,and CF by soil microorganisms,with enhancement factors reaching up to 20,6,and 7times compared to bare soil.The oxidation rates of all rhizosphere soils showed significant differences from bare soil,with Rumex,Artemisia,and Amaranthus exhibiting the best degradation enhancement.Diversity analysis revealed that the microbial richness in most rhizosphere soils was significantly higher than that in bare soil,and the microbial community structure in different rhizosphere soils varied significantly.The rhizosphere effect induced a shift in dominant methanotrophs from Methylophilaceae to Methylocicrobium,Methylomonadaceae,Methylobacter,Methylobacillus,Methylocystis,and Methylococcus.Metabolomics analysis identified Neopetasitenine as a potential key player in enhancing microbial activity.Mechanistic analysis revealed that the enhanced biotransformation capacity of chlorinated alkanes remained crucial for their reduction.
万方数据
维普
