Please use this identifier to cite or link to this item:
Title: Exploring the Effects of Organic Matter Characteristics on Fe(II) Oxidation Kinetics in Coastal Seawater
Authors: Santana Casiano, Juana Magdalena 
González Santana, David 
Devresse, Quentin
Hepach, Helmke
Santana González, Carolina 
Quack, Birgit
Engel, Anja
González Dávila, Melchor 
UNESCO Clasification: 251010 Procesos litorales o sublitorales
221003 Cinética química
Keywords: CDOM
Coastal Seawater
Macaronesia, et al
Issue Date: 2022
Project: Efecto de la Acidificacion Oceanica, la Temperatura y El Contenido de Materia Organica en la Persistencia de Fe(Ii) en El Oceano Atlantico 
Our common future ocean in the Earth system ¿ quantifying coupled cycles of carbon, oxygen, and nutrients for determining and achieving safe operating spaces with respect to tipping points 
Journal: Environmental science & technology 
Abstract: The iron(II) oxidation kinetic process was studied at 25 stations in coastal seawater of the Macaronesia region (9 around Cape Verde, 11 around the Canary Islands, and 5 around Madeira). In a physicochemical context, experiments were carried out to study the pseudo-first-order oxidation rate constant (k′, min-1) over a range of pH (7.8, 7.9, 8.0, and 8.1) and temperature (10, 15, 20, and 25 °C). Deviations from the calculated kcal′ at the same T, pH, and S were observed for most of the stations. The measured t1/2 (ln 2/k′, min) values at the 25 stations ranged from 1.82 to 3.47 min (mean 1.93 ± 0.76 min) and for all but two stations were lower than the calculated t1/2 of 3.21 ± 0.2 min. In a biogeochemical context, nutrients and variables associated with the organic matter spectral properties (CDOM and FDOM) were analyzed to explain the observed deviations. The application of a multilinear regression model indicated that k′ can be described (R = 0.921 and SEE = 0.064 for pH = 8 and T = 25 °C) from a linear combination of three organic variables, k′OM = kcal′-0.11∗ TDN + 29.9*bDOM + 33.4*C1humic, where TDN is the total dissolved nitrogen, bDOM is the spectral peak obtained from colored dissolved organic matter (DOM) analysis when protein-like or tyrosine-like components are present, and C1humic is the component associated with humic-like compounds obtained from the parallel factor analysis of the fluorescent DOM. Results show that compounds with N in their structures mainly explain the observed k′ increase for most of the samples, although other components could also play a relevant role. Experimentally, k′ provides the net result between the compounds that accelerate the process and those that slow it down.
ISSN: 0013-936X
DOI: 10.1021/acs.est.1c04512
Source: Environmental Science and Technology [ISSN 0013-936X], v. 56 (4), p. 2718-2728, (Enero 2022)
Appears in Collections:Artículos
Adobe PDF (2,17 MB)
Show full item record


checked on Nov 19, 2023

Page view(s)

checked on Apr 29, 2023


checked on Apr 29, 2023

Google ScholarTM




Export metadata

Items in accedaCRIS are protected by copyright, with all rights reserved, unless otherwise indicated.