Organic matter character as a critical factor determining the fate and stability of its association with iron in sediments

0562700 - BC 2023 RIV DE eng J - Článek v odborném periodiku
Osafo, Nana O.A. - Jan, Jiří - Valero Soriano, Astolfo Enrique - Porcal, Petr - Petrash, Daniel A. - Borovec, Jakub
Organic matter character as a critical factor determining the fate and stability of its association with iron in sediments.
Journal of Soils and Sediments. Roč. 22, č. 6 (2022), s. 1865-1875. ISSN 1439-0108. E-ISSN 1614-7480
Grant CEP: GA MŠMT(CZ) LM2015075; GA MŠMT(CZ) EF16_013/0001782; GA ČR(CZ) GJ19-15096Y; GA ČR(CZ) GA19-00113S; GA MZe(CZ) QK1810161; GA MZe(CZ) QK22020179
Institucionální podpora: RVO:60077344
Klíčová slova: freshwater reservoir * redox reactivity * sequential extraction * PARAFAC * UV-vis
Obor OECD: Marine biology, freshwater biology, limnology
Impakt faktor: 3.6, rok: 2022
Způsob publikování: Omezený přístup
https://link.springer.com/article/10.1007/s11368-022-03207-x

Purpose Complexes of organic matter (OM) with iron (Fe) oxyhydroxides (OM-Fe) prevent/reduce microbial degradation and enhance its stabilization in soils and sediments. Missing in most studies regarding the quality of OM-Fe complexes is in this study addressed by optical method characterization using absorbance and fluorescence, which is a unique approach in combination with sequential extraction methods. This study finds the quality of OM which promotes the stability of the OM-Fe aggregates with respect to the rate of redox dissolution of Fe mineral phases. Methods Sediment samples from a mesotrophic freshwater reservoir were sequentially extracted to distinguish Fe oxyhydroxides solubility at different dissolution times. This allowed us to assess the OM-Fe association with easily reducible Fe-bearing minerals vs. more stable yet reducible fractions. The quality of the sequentially extracted DOM associated with different redox reactivity mineral phases was evaluated by UV-Vis and fluorescence spectroscopy using a parallel factor analysis (PARAFAC) model. Results Humic-like substances render soluble and labile OM-Fe associations, while non-humic substances enhance the stability of such associations under reducing conditions. In anoxic sediments, non-humic substances are stabilized in the OM-Fe associations. Conclusion This study described the fate of OM-Fe in anoxic sediments by coupling sequential extractions with UV-Vis and fluorescence spectroscopy characterization. This is a new reliable and simple approach for evaluating the stability of OM-Fe aggregates in sediments, soils, and/or wastewater treatment sludge.
Trvalý link: https://hdl.handle.net/11104/0336772