Factors affecting organic matter association with iron under reducing conditions

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F25%3A00641820" target="_blank" >RIV/60077344:_____/25:00641820 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60076658:12310/25:43910553

Výsledek na webu

<a href="https://link.springer.com/article/10.1007/s11368-025-04146-z" target="_blank" >https://link.springer.com/article/10.1007/s11368-025-04146-z</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s11368-025-04146-z" target="_blank" >10.1007/s11368-025-04146-z</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Factors affecting organic matter association with iron under reducing conditions

Popis výsledku v původním jazyce

Purpose: The stability of organic matter (OM) in freshwater sediments is largely determined by its interactions with iron (Fe) oxyhydroxides, which play a crucial role in carbon (C) and Fe cycling, and in regulating nutrient dynamics in soils and sediments. However, under anoxic conditions, different solubility patterns can be observed for reasons that are not yet fully understood. This study aims to elucidate the influence of OM source, concentration, pH, and association mechanisms (coprecipitation vs. sorption) on OM-Fe stability. Methods: Four natural OM sources (NOM) were used to form OM-Fe associations. These sources were used for coprecipitation and sorption of dissolved OM (DOM) onto Fe oxyhydroxides at pH 5 and 7. The experiment was carried out with four different DOC: Fe molar ratios. The stability of the products was evaluated by monitoring the dissolution kinetics of sodium dithionite and the release of Fe2+, dissolved organic carbon (DOC), and changes in DOM composition. Results: Coprecipitation was more efficient than sorption for DOC retention in Fe oxyhydroxides, especially at higher DOC: Fe ratios. Dissolution was about four times slower for coprecipitated OM-Fe compounds than for sorbed ones. For all NOM sources and mechanisms, amidic (proteinaceous) OM fractions were more stable, while aromatic, phenolic, and cellulosic OM were more soluble. Typha biomass showed the highest amidic fraction, while peat was the lowest. Conclusion: These results highlight the role of OM composition in OM-Fe stability and its impact on the stabilization of Fe in freshwater sediments. The trophic level of the aquatic ecosystem and the proportion of the littoral zone can significantly affect the Fe cycle.

Název v anglickém jazyce

Factors affecting organic matter association with iron under reducing conditions

Popis výsledku anglicky

Purpose: The stability of organic matter (OM) in freshwater sediments is largely determined by its interactions with iron (Fe) oxyhydroxides, which play a crucial role in carbon (C) and Fe cycling, and in regulating nutrient dynamics in soils and sediments. However, under anoxic conditions, different solubility patterns can be observed for reasons that are not yet fully understood. This study aims to elucidate the influence of OM source, concentration, pH, and association mechanisms (coprecipitation vs. sorption) on OM-Fe stability. Methods: Four natural OM sources (NOM) were used to form OM-Fe associations. These sources were used for coprecipitation and sorption of dissolved OM (DOM) onto Fe oxyhydroxides at pH 5 and 7. The experiment was carried out with four different DOC: Fe molar ratios. The stability of the products was evaluated by monitoring the dissolution kinetics of sodium dithionite and the release of Fe2+, dissolved organic carbon (DOC), and changes in DOM composition. Results: Coprecipitation was more efficient than sorption for DOC retention in Fe oxyhydroxides, especially at higher DOC: Fe ratios. Dissolution was about four times slower for coprecipitated OM-Fe compounds than for sorbed ones. For all NOM sources and mechanisms, amidic (proteinaceous) OM fractions were more stable, while aromatic, phenolic, and cellulosic OM were more soluble. Typha biomass showed the highest amidic fraction, while peat was the lowest. Conclusion: These results highlight the role of OM composition in OM-Fe stability and its impact on the stabilization of Fe in freshwater sediments. The trophic level of the aquatic ecosystem and the proportion of the littoral zone can significantly affect the Fe cycle.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10503 - Water resources

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Soils and Sediments

ISSN

1439-0108

e-ISSN

1614-7480

Svazek periodika

25

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

17

Strana od-do

3117-3133

Kód UT WoS článku

001589968200001

EID výsledku v databázi Scopus

2-s2.0-105018645009