Mathieu Pédrot

TL;DR: In this paper, controlled incubations of a wetland soil were performed under oxic and anoxic conditions to investigate the extent to which the following processes account for this phenomenon: i) production of organic metabolites by microbes during soil reduction, ii) release of organic matter (OM) from Mn- and Fe-oxyhydroxides that undergo reductive dissolution, and iii) desorption of OM from soil minerals due to pH changes.

TL;DR: Himic substances are a major control of REE speciation and REE fractionation patterns as well since the humic substance/metal ratio was the key parameter controlling the REE pattern shape.

TL;DR: Results suggest that, in wetlands but also elsewhere where mixed organic matter-Fe colloids occur, Fe nanoparticles closely associated with organic matter represent a bioavailable Fe source much more accessible for microfauna than do crystallized Fe oxyhydroxides.

TL;DR: In this article, anoxic and oxic wetland soil incubation experiments, combined with analyses of soil solutions sampled from a natural wetland during a reduction event, are used to test the possibility that rare earth elements (REE) could be used as a tool to identify the soil phases contributing to trace metal solubilization.

TL;DR: In this article, the effect of Fe on humic acid binding was investigated by coupling laboratory experiments and modeling calculations using PHREEQC/Model VI, showing that Fe has the same relative affinity for carboxylic and phenolic HA sites as LREE and HREE, respectively.