Microbiological Study of Yamal Lakes: A Key to Understanding the Evolution of Gas Emission Craters
Abstract
:1. Introduction
2. Study Area
3. Materials and Methods
3.1. Sample Collection and Characterization
3.2. Analytical Techniques
3.3. Isotopic Composition of Carbon Compounds
3.4. Radiotracer Experiments
3.5. Cell Counts
3.6. DNA Extraction and Sequencing and Read-Centric Analysis
4. Results
5. Discussion
6. Conclusions
- Yamal lakes share similarities with the tundra and boreal lakes located in other areas of the permafrost zone. Slow-flowing microbial processes are characteristic of both types of lakes (GEC and background), which is expected for the cold climate of the studied area. The bacterial communities of both types of studied lakes were dominated by the taxa typically found in thermokarst lakes and other permafrost-affected habitats. Both types of studied lakes were inhabited by aerobic methanotrophs of the genus Methylobacter: the most frequently detected methanotrophs in various freshwater environments, including boreal thermokarst and non-thermokarst lakes. The nitrate-dependent ANME 2d detected in both GEC and background lakes were also found previously in other thermokarst lakes. Methane concentrations in the sediments of background lakes were within the wide range of concentrations known for mesotrophic and dystrophic lakes of the boreal zone, and representatives of methanogenic archaea in background lakes were similar to those found in other boreal basins.
- At the same time, the GEC lakes essentially differed from the background ones by low rates of anaerobic processes (methanogenesis and sulfate reduction), a reliably lower methane concentration, and low diversity and abundance of methanogenic archaea in the sediments. Archaea in the GEC lakes were probably allochthonous microbiota from the surface and active-layer runoff. Thus, GEC lakes could be distinguished from other exogenous lakes based on their weak methanogenic population and activity.
- It can be gingerly assumed that the very slow rates of anaerobic microbial processes indicate a transformation of the newly formed water bodies (i.e., GEC lakes) into real lakes. This may relate not only to GEC lakes, but also to newly formed thermokarst lakes.
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Water Object | Total Concentration of Main Ions, mg∙L−1 | Na+ mg/eq % | Cl− mg/eq % | Ca2+ mg/eq % | HCO3− mg/eq % | DOC mg∙L−1 | t °C Winter/Summer | pH | CH4 μmol∙L−1 Winter/Summer |
---|---|---|---|---|---|---|---|---|---|
GEC lakes | 152–402 | 52–87 | 18–63 | 3–21 | 0–70 | 4.3–50.4 | (−0.08)/12.7 | 6.61–7.96 | 0.04–36.8/0.4–43.2 |
GEC ice walls | 3–201 | 28–78 | 4–48 | 5–52 | 1–65 | 5.6–31.5 | - | - | 0.08–93.7 |
Background lakes | 25–471 | 27–92 | 13–98 | 2–50 | 0–84 | 2.7–14.2 | 1.2/16.9 | 5.7–8.7 | 0.09–341/0–4.5 |
Lake ice | - | - | - | - | - | - | - | - | 0.05–1.84 |
Ponds | 1381–1946 | 47–71 | 87–94 | 11–23 | 0–4 | 7.6–10.9 | - | 5.9–7.43 | - |
Rain | 5.2 | 8–31 | 41–50 | 45–55 | 0.2–0.4 | - | - | - | - |
River | 141–147 | 55–58 | 56–91 | 14 | 6–42 | - | - | - | |
Snow | 4.4–51 | 12–71 | 24–86 | 7–43 | 3–56 | - | - | 5.19–7.52 | - |
Thermocirque | 988 | 45 | 24 | 22 | 66 | 243 | - | 7.6 | - |
Parameter | LK001 | LK015 | GEC-1 | GEC-2 |
---|---|---|---|---|
Geology | IVth coastal-marine plain, clayey-silty deposits, altitude 40–41 m (Baltic) | Concave slope within IVth coastal-marine plain, clayey-silty deposits, altitude 40–43 m (Baltic) | ||
lake surface’s average altitude (Baltic), m | 12.8 | 11.4 | 33 | |
lake area, ha | 37.16 | 9.92 | 0.57 | 1.35 |
lake depth mean/max | 4.4/16.9 | 7.7/23.2 | 2.6/4.9 | 1.0/2.5 |
Coastal lithology | Clay, silt, sand, tabular ground ice covered by talus | Clay, silt, peat, ice wedges, tabular ground ice | Clay, silt, tabular ground ice | |
Leading coastal process | Thermoerosion | Thermodenudation | Coastal thermoerosion | |
DOC, mg∙L−1 (SF/BO) | 3.6/4.2 | 4.6/5.0 | 10.1/10.5 | 5.8 |
Methane, μmol∙L−1 (SF/BO) | 0.25/6.1 | 0.13/62.8 | 16/21 ± 0.2 | 0.42 |
Water temperature | 1.4–2.0 | 1.3–3.1 °C | 0.2 | 0.3 |
Lake | TNM (103 Cell∙mL−1) | AOF (103 Cell∙mL−1) |
---|---|---|
LK001 | 200 ± 50 | 60 ± 20 |
LK015 | 340 ± 70 | 70 ± 20 |
GEC-1 | 420 ± 70 | 30 ± 10 |
GEC-2 | 150 ± 40 | 25 ± 10 |
Sample | Bottom Water | Bottom Sediments (0–14-cm Depth) | ||||||
---|---|---|---|---|---|---|---|---|
Lake | LK001 | LK015 | GEC-1 | GEC-2 | LK001 | LK015 | GEC-1 | GEC-2 |
Chemoorganotrophic Actinobacteria (% to total 16S rRNA reads) | ||||||||
Ilumatobacter | 9.1 | 8.5 | 15.5 | 11.9 | 0 | 0 | 0.1 | 0.6 |
Ca. “Nanopelagicus” | 10.4 | 7.9 | 0.06 | 0 | 0.01 | 0 | 0 | 0 |
Ca. “Planktophila” | 11.9 | 17.7 | 16.8 | 13.4 | 0.01 | 0.07 | 4.6 | 3.2 |
Betaproteobacteria (% to total 16S rRNA reads) | ||||||||
Methylotrophic | 3.5 | 8.1 | 1.7 | 1.4 | 0.16 | 0.16 | 0.2 | 0.7 |
Involved in N cycle | 5.7 | 1.7 | 0.5 | 1.2 | 0.17 | 0.3 | 4.8 | 0.6 |
Ferrous-iron-oxidizing | 2.0 | 0.7 | 0 | 0.01 | 0.08 | 3.9 | 9.98 | 1.1 |
Chemoorganotrophic | 2.36 | 3.95 | 20.97 | 8.7 | 0.25 | 4.5 | 5.9 | 13.2 |
Sulfur-oxidizing | 0 | 0 | 0.01 | 0 | 0.7 | 3.0 | 0.04 | 0.07 |
Gammaproteobacteria (% to total 16S rRNA reads) | ||||||||
Methanotrophic | 7.6 | 18.0 | 17.9 | 9.1 | 1.04 | 0.3 | 1.8 | 1.05 |
Chemoorganotrophic | 7.0 | 0.03 | 3.5 | 38.2 | 0.01 | 1.9 | 0.1 | 17.8 |
Deltaproteobacteria (% to total 16S rRNA reads) | ||||||||
Sulfate-reducing | 0 | 0 | 0 | 0 | 0.11 | 2.53 | 2.2 | 4.3 |
Sample | Near Bottom Water | Bottom Sediments (0–14-cm Depth) | ||||||
---|---|---|---|---|---|---|---|---|
Lake | LK001 | LK015 | GEC-1 | GEC-2 | LK001 | LK015 | GEC-1 | GEC-2 |
% to Total 16S rRNA Reads | ||||||||
Methanoregula | 0.12 | 0.16 | 0.05 | 0.02 | 22.93 | 15.27 | 0.06 | 0.08 |
Methanosarcina | 0 | 0 | 0.01 | 0 | 0.04 | 0.78 | 2.91 | 0.13 |
Methanosaeta | 0 | 0 | 0 | 0 | 3.61 | 5.69 | 0.64 | 0.01 |
Methanomassiliicoccus | 0 | 0 | 0 | 0 | 1.18 | 0.88 | 0.06 | 0 |
ANME-2d | 0 | 0 | 0 | 0.15 | 1.80 | 0.04 | 2.27 | 0.15 |
Other archaea | 0.63 | 0.77 | 0.12 | 0.29 | 29.49 | 28.14 | 4.83 | 0.29 |
Total archaea | 0.76 | 0.94 | 0.18 | 0.67 | 59.05 | 50.80 | 10.77 | 0.67 |
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Savvichev, A.; Leibman, M.; Kadnikov, V.; Kallistova, A.; Pimenov, N.; Ravin, N.; Dvornikov, Y.; Khomutov, A. Microbiological Study of Yamal Lakes: A Key to Understanding the Evolution of Gas Emission Craters. Geosciences 2018, 8, 478. https://doi.org/10.3390/geosciences8120478
Savvichev A, Leibman M, Kadnikov V, Kallistova A, Pimenov N, Ravin N, Dvornikov Y, Khomutov A. Microbiological Study of Yamal Lakes: A Key to Understanding the Evolution of Gas Emission Craters. Geosciences. 2018; 8(12):478. https://doi.org/10.3390/geosciences8120478
Chicago/Turabian StyleSavvichev, Alexander, Marina Leibman, Vitaly Kadnikov, Anna Kallistova, Nikolai Pimenov, Nikolai Ravin, Yury Dvornikov, and Artem Khomutov. 2018. "Microbiological Study of Yamal Lakes: A Key to Understanding the Evolution of Gas Emission Craters" Geosciences 8, no. 12: 478. https://doi.org/10.3390/geosciences8120478
APA StyleSavvichev, A., Leibman, M., Kadnikov, V., Kallistova, A., Pimenov, N., Ravin, N., Dvornikov, Y., & Khomutov, A. (2018). Microbiological Study of Yamal Lakes: A Key to Understanding the Evolution of Gas Emission Craters. Geosciences, 8(12), 478. https://doi.org/10.3390/geosciences8120478