Fe-catalyzed sulfide oxidation in hydrothermal plumes is a source of reactive oxygen species to the ocean - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Proceedings of the National Academy of Sciences of the United States of America Année : 2021

Fe-catalyzed sulfide oxidation in hydrothermal plumes is a source of reactive oxygen species to the ocean

Résumé

Historically, the production of reactive oxygen species (ROS) in the ocean has been attributed to photochemical and biochemical reactions. However, hydrothermal vents emit globally significant inventories of reduced Fe and S species that should react rapidly with oxygen in bottom water and serve as a heretofore unmeasured source of ROS. Here, we show that the Fe-catalyzed oxidation of reduced sulfur species in hydrothermal vent plumes in the deep oceans supported the abiotic formation of ROS at concentrations 20 to 100 times higher than the average for photoproduced ROS in surface waters. ROS (measured as hydrogen peroxide) were determined in hydrothermal plumes and seeps during a series of Alvin dives at the North East Pacific Rise. Hydrogen peroxide inventories in emerging plumes were maintained at levels proportional to the oxygen introduced by mixing with bottom water. Fenton chemistry predicts the production of hydroxyl radical under plume conditions through the reaction of hydrogen peroxide with the abundant reduced Fe in hydrothermal plumes. A model of the hydroxyl radical fate under plume conditions supports the role of plume ROS in the alteration of refractory organic molecules in seawater. The ocean’s volume circulates through hydrothermal plumes on timescales similar to the age of refractory dissolved organic carbon. Thus, plume-generated ROS can initiate reactions that may affect global ocean carbon inventories.
Fichier principal
Vignette du fichier
Shaw et al. - 2021 - Fe-catalyzed sulfide oxidation in hydrothermal plu.pdf (920.73 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03366294 , version 1 (05-10-2021)

Identifiants

Citer

Timothy Shaw, George Luther, Richard Rosas, Véronique Oldham, Nicole Coffey, et al.. Fe-catalyzed sulfide oxidation in hydrothermal plumes is a source of reactive oxygen species to the ocean. Proceedings of the National Academy of Sciences of the United States of America, 2021, 118 (40), pp.e2026654118. ⟨10.1073/pnas.2026654118⟩. ⟨hal-03366294⟩
20 Consultations
33 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More