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Published on: September 11, 2016
Different Ferromanganese Concretion Morphologies Host Distinct Microbial Communities and Metal Accumulation Patterns
Renata Majamäki1, Joonas Wasiljeff1, Lotta Purkamo1
1Geological Survey of Finland (GTK), Espoo, Finland.
Environmental Microbiology
|July 23, 2026
Summary
Microbes significantly impact metal accumulation in different shapes of ferromanganese concretions. Distinct microbial communities in these seafloor formations influence nutrient and metal cycling.
Area of Science:
- Marine Geology
- Geomicrobiology
- Biogeochemistry
Background:
- Ferromanganese (Fe-Mn) concretions are key seafloor deposits.
- Microbial roles in metal accumulation are suggested but not fully understood.
- Concretion morphotypes and their associated microbial communities require detailed investigation.
Purpose of the Study:
- To investigate microbial influence on trace metal and rare-earth element cycling in Baltic Sea Fe-Mn concretions.
- To characterize microbial communities across distinct concretion morphotypes (crust, discoidal, spheroidal).
- To assess the impact of microbial activity on metal enrichment and release.
Main Methods:
- 15-week microcosm incubation experiments with biotic and abiotic treatments.
- Elemental analysis of Fe-Mn concretions.
- Microbial community composition analysis using 16S rRNA sequencing (implied).
Main Results:
- Microbes enhanced metal incorporation in discoidal and spheroidal Fe-Mn concretions.
- Distinct microbial communities were found in crust, discoidal, and spheroidal morphotypes.
- Pseudomonadota dominated, with specific bacteria involved in Fe/Mn cycling, methane oxidation, and nitrogen cycling.
Conclusions:
- Microbial communities vary significantly among Fe-Mn concretion morphotypes.
- These distinct microbial communities play a role in metal enrichment and biogeochemical cycling on the seafloor.
- Understanding these microbial associations is crucial for predicting seafloor processes.
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