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When wet Arctic tundra soils begin to freeze in the fall, an unfrozen layer remains between the frozen surface and deeper permafrost layers. This period is known as the zero curtain, as liquid water keeps the temperature of this soil layer near 0 Celsius (C) while latent heat is gradually dissipated. This project investigates the microbes that are metabolically active in the unfrozen layer during the fall zero curtain period and compares this community to that which is active in the late summer at the same depth (10-20 centimeters (cm)). This dataset contains the abundance and taxonomic designation of distinct 16S ribosomal ribonucleic acid (16S rRNA) sequences (operational taxonomic units, OTU's) associated with samples in this study. These data complement the sequences and metadata deposited in GenBank Bioproject PRJNA780202.
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Methyl-coenzyme M reductase alpha subunit (mcrA) transcripts from Arctic tundra soil near Utqiagvik, Alaska, 2018
When wet Arctic tundra soils begin to freeze in the fall, an unfrozen layer remains between the frozen surface and deeper permafrost layers. This period is known as the zero curtain, as liquid water keeps the temperature of this soil layer near 0 Celsius (C) while latent heat is gradually dissipated. This project investigates the methanogenic Archaea that are metabolically active in the unfrozen layer during the fall zero curtain period and compares this community to that which is active in the late summer at the same depth (10-20 centimeters (cm)). This dataset contains the abundance of distinct partial mcrA (Methyl-coenzyme M reductase alpha subunit) gene sequences (operational taxonomic units, OTU's defined at 16% similarity) amplified from messenger ribonucleic acid (mRNA) extracted from soil samples in this study. These data complement the sequences deposited in GenBank (accession numbers OL505703-OL505708).
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- Award ID(s):
- 1702797
- PAR ID:
- 10310647
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Arctic tundra mcrA methanogen microbial community
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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When wet Arctic tundra soils begin to freeze in the fall, an unfrozen layer remains between the frozen surface and deeper permafrost layers. This period is known as the zero curtain, as liquid water keeps the temperature of this soil layer near 0 Celsius (C) while latent heat is gradually dissipated. Significant methane emissions have been observed during this period but the role of concurrent biological production vs escape of stored methane requires more study. This dataset includes dissolved methane concentrations from the active layer (upper 35 centimeters (cm)) of Arctic tundra soils during the fall zero curtain period and in the spring, at the beginning of the thaw period. These data help address the question of biological methane production and storage during the fall.more » « less
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