Dependence of Biotic and Abiotic H2O2 and •OH Production on the Redox Conditions and Compositions of Sediment during Oxygenation

• DOI: 10.1021/acs.est.3c10424
• Publication Date: 2024-02-13T18:51:12Z
• Authors: Na Zhang; Ying Liu; Zhenchen Wan; Yanting Zhang; Wenjing Xie; Peng Zhang; Man Tong; Songhu Yuan
• Keywords: Biotic component

Reactive oxygen species (ROS) production in O2-perturbed subsurface environments has been increasingly documented recent years. However, the constraining conditions under which abiotic and/or biotic mechanisms predominate for ROS remain ambiguous. Here, we demonstrate that mechanism, and abiotic, is determined by sediment redox properties compositions. Upon oxygenation of 10 field sediments, cumulative H2O2 concentrations reached up to 554 μmol/kg within 2 h. The autoclaving sterilization experiments showed could be produced both processes depending on conditions. only process produce significant levels •OH, yield was closely related components, particularly Fe(II) organic matter. bound with matter led high yields •OH production. Sediment contributed appearance groundwater, mechanism producing higher instantaneous than mechanism. These findings reveal conditions, compositions, texture sediments collectively control production, assists identification hotspots understanding distribution utilization subsurface.