1. Denitrification mechanism in oxygen-rich aquatic environments through long-distance electron transfer.
- Author
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Wei, Ming-Zhi, Liu, Jin-Wei, Yang, Qin-Zheng, Xue, An, Wu, Hao, Ni, Jin-Ren, Winter, Lea R., Elimelech, Menachem, and Zhao, Hua-Zhang
- Subjects
CHARGE exchange ,ELECTRON donors ,DENITRIFICATION ,LAKE sediments ,RIVER sediments ,ELECTROPHILES - Abstract
The lack of electron donors in oxygen-rich aquatic environments limits the ability of natural denitrification to remove excess nitrate, leading to eutrophication of aquatic ecosystems. Herein, we demonstrate that electron-rich substances in river or lake sediments could participate in long-distance electron rebalancing to reduce nitrate in the overlying water. A microstructure containing Dechloromonas and consisting of an inner layer of green rust and an outer layer of lepidocrocite forms in the sediment-water system through synergetic evolution and self-assembly. The microstructure enables long-distance electron transfer from the sediment to dilute nitrate in the overlying water. Specifically, the inner green rust adsorbs nitrate and reduces the kinetic barrier for denitrification via an Fe(II)/Fe(III) redox mediator. Our study reveals the mechanism of spontaneous electron transfer between distant and dilute electron donors and acceptors to achieve denitrification in electron-deficient aquatic systems. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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