Redox dynamics and metal cycling in the carbonate-buffered sediment–water interface of the ferruginous and sulfatic Lake Medard, Czech Republic
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F25%3A00638660" target="_blank" >RIV/60077344:_____/25:00638660 - isvavai.cz</a>
Alternative codes found
RIV/60076658:12310/25:43910785 RIV/00025798:_____/25:10169514
Result on the web
<a href="https://pubs.geoscienceworld.org/sepm/jsedres/article-abstract/95/4/707/653835/Redox-dynamics-and-metal-cycling-in-the-carbonate?redirectedFrom=fulltext" target="_blank" >https://pubs.geoscienceworld.org/sepm/jsedres/article-abstract/95/4/707/653835/Redox-dynamics-and-metal-cycling-in-the-carbonate?redirectedFrom=fulltext</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.2110/jsr.2024.155" target="_blank" >10.2110/jsr.2024.155</a>
Alternative languages
Result language
angličtina
Original language name
Redox dynamics and metal cycling in the carbonate-buffered sediment–water interface of the ferruginous and sulfatic Lake Medard, Czech Republic
Original language description
Lake Medard (LM), a post-mining lake in the Czech Republic with stratified, sulfate- and iron-rich bottom waters, serves as a natural laboratory to study sediment–water-interface (SWI) dynamics where steep aqueous redox gradients are present. This study investigates the interplay of redox conditions, microbial activity, and sedimentary processes, revealing that short-term Eh fluctuations (80–100 mV) in the bottom water significantly mobilize rare earth elements (REE) and influence the partitioning of other redox-sensitive elements such as vanadium (V) and arsenic (As) from reactive iron (Fe)- and manganese (Mn)-oxyhydroxides during early diagenesis. While carbonate phases like siderite primarily retain their REE signatures, they can incorporate REE released during these redox shifts. Spectroscopic analyses confirms the presence of FeOOH polymorphs (goethite and lepidocrocite) in organo-mineral aggregates in the upper sediments. Sequential extractions shows that under stronger reducing conditions (Eh ≈ –190 mV), As predominantly associates with carbonates, shifting to Fe(III)-oxyhydroxides at higher Eh (≈ –80 mV). Isotope analyses (d13C) indicate that the bulk sediment carbonate is detrital, sourced from Miocene strata. Authigenic pyrite in LM sediments exhibits d34Spy values (–35.1 to –23.0%), reflecting microbial sulfate reduction. However, the accumulation of the byproduct sulfide, and thus pyrite stabilization, is limited by the low availability of labile organic substrates and the reoxidation of sulfide by Fe(III)-oxyhydroxides. These findings highlight the sensitivity of geochemical signals in sediments to subtle redox shifts and improve our interpretation of ancient deposits formed under dynamic water column redox conditions.
Czech name
—
Czech description
—
Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10511 - Environmental sciences (social aspects to be 5.7)
Result continuities
Project
<a href="/en/project/GJ19-15096Y" target="_blank" >GJ19-15096Y: Microbially induced iron, nitrogen and phosphorus co-recycling and transient decoupling in aqueous ferruginous ecosystems</a><br>
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of Sedimentary Research
ISSN
1527-1404
e-ISSN
1938-3681
Volume of the periodical
95
Issue of the periodical within the volume
4
Country of publishing house
US - UNITED STATES
Number of pages
16
Pages from-to
707-722
UT code for WoS article
001666225000002
EID of the result in the Scopus database
2-s2.0-105013135169