Algal-derived dissolved organic matter accelerates mercury methylation under cyanobacterial blooms in the sediment of eutrophic lakes

Copyright © 2024. Published by Elsevier Inc..

Mercury (Hg), especially in the form of methylmercury (MeHg), poses a significant threat to both organisms and the environment due to its extreme toxicity. While methylation process of Hg in sediments has been extensively studied, recognition of its associated risks and mechanisms during cyanobacterial blooms remains limited. This study investigated the distribution characteristics of Hg and MeHg in sediments of Taihu Lake, China. The concentration of Hg and MeHg varied within the range of 96.0-212.0 ng g-1 and 0.1-0.5 ng g-1, respectively. Higher ecological risks of Hg were found in algal-dominated regions compared to macrophyte areas. The significant correlations observed between Hg, MeHg, and algal-derived dissolved organic matter (ADOM) components C1 and C2 in algal-dominated regions indicate a close association between ADOM components and the Hg methylation process. These components are involved in the absorption or complexation of Hg, participate in redox reactions, and modulate microbial activity. The dsrB gene in sulfate-reducing bacteria (SRB) was found to accelerate the metabolic pathways of Hg methylation. These findings indicate that ADOM could enhance the methylation process of Hg during cyanobacterial blooms, which warrants attention.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:251

Enthalten in:

Environmental research - 251(2024), Pt 2 vom: 16. März, Seite 118734

Sprache:

Englisch

Beteiligte Personen:

Wang, Yan [VerfasserIn]
Zhang, Lan [VerfasserIn]
Chen, Xiang [VerfasserIn]
Li, Cai [VerfasserIn]
Ding, Shiming [VerfasserIn]
Yan, Jiabao [VerfasserIn]
Xiao, Jing [VerfasserIn]
Wang, Bin [VerfasserIn]
Xu, Lv [VerfasserIn]
Hang, Xiaoshuai [VerfasserIn]

Links:

Volltext

Themen:

Cyanobacteria
Diffusive gradient in thin films
Dissolved organic matter
Journal Article
Methylmercury
Sediment-water interface
Sulfate-reducing bacteria

Anmerkungen:

Date Revised 19.03.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1016/j.envres.2024.118734

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369835433