RT journal article
T1 Biogeochemical changes at the sediment–water interface during redox transitions in an acidic reservoir: exchange of protons, acidity and electron donors and acceptors
A1 Corzo Rodríguez, Alfonso
A1 Jiménez Arias, Juan Luis
A1 Torres, E.
A1 García Robledo, Emilio Guillermo
A1 Lara Rallo, Francisco Miguel
A1 Papaspyrou, Sokratis
A2 Biología
A2 Didáctica
K1 Acid mine drainage
K1 Lake
K1 Microscale
K1 Microsensor
K1 Oxic-anoxic interface
K1 Acidity
K1 Iron
K1 Sulfur
K1 Fluxes at the sediment–water interface
K1 Diffusive oxygen uptake
K1 Carbon mineralisation calculations
K1 Huelva
K1 Iberian pyrite belt
K1 Sancho reservoir
AB Redox transitions induced by seasonal changes in water column O2 concentration can have important effects on solutes exchange across the sediment–water interface in systems polluted with acid mine drainage (AMD), thus influencing natural attenuation and bioremediation processes. The effect of such transitions was studied in a mesocosm experiment with water and sediment cores from an acidic reservoir (El Sancho, SW Spain). Rates of aerobic organic matter mineralization and oxidation of reduced inorganic compounds increased under oxic conditions (OX). Anaerobic process, like Fe(III) and sulfate reduction, also increased due to higher O2 availability and penetration depth in the sediment, resulting in higher regeneration rates of their corresponding anaerobic e− acceptors. The contribution of the different processes to oxygen uptake changed considerably over time. pH decreased due to the precipitation of schwertmannite and the release of H+ from the sediment, favouring the dissolution of Al-hydroxides and hydroxysulfates at the sediment surface. The increase in dissolved Al was the main contributor to water column acidity during OX. Changes in organic matter degradation rates and co-precipitation and dissolution of dissolved organic carbon and nitrogen with redox-sensitive Fe(III) compounds affected considerably C and N cycling at the sediment–water interface during redox transitions. The release of NO2                             − and NO3                             − during the hypoxic period could be attributed to ammonium oxidation coupled to ferric iron reduction (Feammox). Considering the multiple effects of redox transitions at the sediment–water interface is critical for the successful outcome of natural attenuation and bioremediation of AMD impacted aquatic environments.
PB Springer International Publishing
SN 1573-515X
YR 2018
FD 2018
LK http://hdl.handle.net/10498/32953
UL http://hdl.handle.net/10498/32953
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 06-nov-2026