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Updated: Jun 8, 2026
07:26
Visualizing Methane-Cycling Microbial Dynamics in Coastal Wetlands
Published on: January 31, 2025
The methane cycle in ferruginous Lake Matano.
S A Crowe1, S Katsev, K Leslie
1Earth and Planetary Sciences, McGill University, Montréal, Québec, Canada.
Geobiology
|September 22, 2010
Summary
In Lake Matano, methane (CH₄) fuels microbial life and carbon cycling, even in iron-rich waters. Methanogens and methanotrophs likely played key roles in ancient Archean oceans.
Area of Science:
- Geomicrobiology
- Biogeochemistry
- Environmental Science
Background:
- Lake Matano, Indonesia, is a unique ferruginous basin with abundant iron oxides.
- Over 50% of organic matter is degraded by methanogenesis, despite high iron.
- High concentrations of methane (CH₄) exist in anoxic bottom waters.
Purpose of the Study:
- Investigate methane cycling and its microbial drivers in Lake Matano.
- Determine the role of methanogenesis and methane oxidation in this iron-rich environment.
- Explore implications for early Earth ecosystems.
Main Methods:
- Analysis of dissolved inorganic carbon (ΣCO₂) and carbon isotopes (δ¹³C).
- Thermodynamic modeling of microbial metabolisms.
- Flux calculations for iron and manganese.
- 16S rRNA gene cloning to identify microbial communities.
Main Results:
- Methane is oxidized near the pycnocline, with evidence of anaerobic oxidation.
- Anaerobic methane oxidation is likely coupled to iron and manganese reduction.
- Methanogens capable of acetoclastic and hydrogenotrophic pathways were identified.
- Methane plays a significant role in carbon cycling in this Fe-rich system.
Conclusions:
- Lake Matano's microbial ecosystems provide insights into potential Archean Ocean conditions.
- Methanogens and methanotrophs may have been crucial components of early Earth's marine ecosystems.
- Iron-rich environments support significant methane cycling and microbial activity.
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