Sediment arsenic remediation by submerged macrophytes via root-released O2 and microbe-mediated arsenic biotransformation

Copyright © 2023 Elsevier B.V. All rights reserved..

Arsenic (As)-contaminated water restoration is extremely challenging because As remobilization from sediments can result in episodic or long-term release of As to the overlying water. In this study, by combining high-resolution imaging techniques with microbial community profiling, we examined the feasibility of utilizing the rhizoremediation of submerged macrophytes (Potamogeton crispus) to decrease As bioavailability and regulate its biotransformation in sediments. Results showed that P. crispus considerably decreased the rhizospheric labile As flux to lower than 4 pg cm-2 s-1 from larger than 7 pg cm-2 s-1, suggesting its effectiveness in promoting As retention in sediments. Iron plaques induced by radial oxygen loss from roots decreased the mobility of As by sequestering it. Additionally, Mn-oxides may act as an oxidizer for the oxidation of As(III) to As(V) in the rhizosphere, which can further increase the As adsorption owing to the strong binding affinity between As(V) and Fe-oxides. Furthermore, microbially mediated As oxidation and methylation were intensified in the microoxic rhizosphere, which decreased the mobility and toxicity of As by changing its speciation. Our study demonstrated that root-driven abiotic and biotic transformation contribute to As retention in sediments, which lays a foundation for applying macrophytes to the remediation of As-contaminated sediments.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:449

Enthalten in:

Journal of hazardous materials - 449(2023) vom: 05. Mai, Seite 131006

Sprache:

Englisch

Beteiligte Personen:

Li, Cai [VerfasserIn]
Ding, Shiming [VerfasserIn]
Ma, Xin [VerfasserIn]
Wang, Yan [VerfasserIn]
Sun, Qin [VerfasserIn]
Zhong, Zhilin [VerfasserIn]
Chen, Musong [VerfasserIn]
Fan, Xianfang [VerfasserIn]

Links:

Volltext

Themen:

059QF0KO0R
Aquatic plants
Arsenic
Arsenic cycling
Iron plaque
Journal Article
N712M78A8G
Oxides
Phytoremediation
Research Support, Non-U.S. Gov't
Sediment
Water

Anmerkungen:

Date Completed 07.03.2023

Date Revised 17.03.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jhazmat.2023.131006

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM353081728