Variability in the production of organic ligands, by Synechococcus PCC 7002, under different iron scenarios

Samperio-Ramos, Guillermo; Santana‐Casiano, J. Magdalena; González‐Dávila, Melchor

doi:10.1007/s10872-017-0457-6

Cited by 3 publications

(1 citation statement)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Culture studies carried out in laboratories show a high dependence of k′ on the content of DOC. 59,60 However, the same does not occur with oceanic samples 12,23 presumably because the dilution factor in the ocean may be important.…”

Section: Resultsmentioning

confidence: 99%

Exploring the Effects of Organic Matter Characteristics on Fe(II) Oxidation Kinetics in Coastal Seawater

Santana-Casiano

González-Santana

Devresse

et al. 2022

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

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 k cal ′ at the same T, pH, and S were observed for most of the stations. The measured t 1/2 (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 t 1/2 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 = k cal ′ −0.11* TDN + 29.9*b DOM + 33.4*C1humic, where TDN is the total dissolved nitrogen, b DOM 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.

show abstract