Evaluating the metabolic functional profiles of the microbial community and alfalfa (Medicago sativa) traits affected by the presence of carbon nanotubes and antimony in drained and waterlogged sediments

• Published in: Journal of hazardous materials Vol. 420; p. 126593
• Main Authors: Cao, Weicheng, Zhu, Rilong, Gong, Jilai, Yang, TingYu, Zeng, Guangming, Song, Biao, Li, Juan, Fang, Siyuan, Qin, Meng, Qin, Lei, Chen, Zengping, Mao, Xiaoqian
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2021
• Subjects: Accumulation; Antimony speciation; Metabolic function; Microbial community; Phytotoxicity; Phytotoxicity; Microbial community; Accumulation; Antimony speciation; Metabolic function
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126593

Antimony (Sb) is the ubiquitous re-emerging contaminant greatly accumulated in sediments which has been revealed risky to ecological environment. However, the impacts of Sb (III/V) on microbes and plants in sediments, under different water management with presence of engineering materials are poorly understood. This study conducted sequential incubation of sediments (flooding, draining and planting) with presence of multiwall carbon nanotubes (MWCNTs) and Sb to explore the influence on microbial functional diversity, Sb accumulation and alfalfa traits. Results showed that water management and planting led to greater impacts of sediment enzyme activities and microbial community metabolic function and bioavailable Sb fractions (defined as sum of acid-soluble fraction and reducible fraction, F1 + F2). Available fractions of Sb (V) showed higher correlation to microbial metabolism (r = 0.933) than that of Sb (III) (r = −0.480) in planting stage. MWCNTs with increasing concentrations (0.011%, w/w) positively correlated to microbial community metabolic function in planting stage whereas resulted in decreasing of Sb (III/V) concentrations in alfalfa, although 0.01% MWCNT led to increase of Sb (V) and decrease of Sb (V) by 50.97% and 32.68% respectively. This study provided information for investigating combined ecological impacts of heavy metal and engineering materials under different water managing sediments. [Display omitted] •0.01% MWCNTs increased Sb (V) by 47.01% but decreased Sb (III) by 49.10% in overlying water.•Available Sb in Sb (V) treatments was highly correlated with MWCNTs concentrations.•Available Sb (V) had higher correlations to microbial metabolism than Sb (III) in planting stage.•Highest enzyme activities and microbial metabolism functions were observed in planting stage.•Sb (III)/Sb (V) posed opposite correlations to biomass and plant Sb concentrations.