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SCIENCE

The Claim

Decomposers break down dead organisms and return carbon to soils and the atmosphere.

Verified by Lenz ·

The Short Version

Decomposers are a core part of the carbon cycle. Evidence from major scientific and educational sources shows they break down dead organisms, release carbon to the atmosphere, and contribute carbon to soils through organic matter formation. The exact pathway and proportion vary by environment, but the claim accurately states their general role.

Caveats

  • The proportion of carbon ending up in soil versus the atmosphere varies with temperature, moisture, oxygen, and ecosystem conditions.
  • Under low-oxygen conditions, decomposition can produce methane as well as carbon dioxide.
  • The claim is a general description of the carbon cycle, not a statement that every decomposition event returns carbon equally or simultaneously to both places.

The Receipts

  1. IPCC Special Report on Climate Change and Land (SRCCL) – Chapter 2: Land–Climate Interactions

    IPCC

  2. The role of soil microbes in the global carbon cycle

    Proceedings of the National Academy of Sciences (via NCBI PMC)

  3. Unrevealing the potential of microbes in decomposition of organic matter and agriculture sustainability

    PubMed

  4. DOE Explains... the Carbon Cycle

    U.S. Department of Energy

  5. The Role of Microorganisms in Climate Change: Carbon Cycling and Greenhouse Gas Production

    Allied Academies (Journal article)

  6. Decomposers | Environmental Sciences | Research Starters

    EBSCO Research Starters

  7. The carbon cycle (article) | Ecology

    Khan Academy

  8. CARBON DIOXIDE AND THE CARBON CYCLE

    NOAA Global Monitoring Laboratory

  9. How soil microbes affect the global carbon cycle

    Great Lakes Bioenergy Research Center (University of Wisconsin–Madison & DOE Bioenergy Center)

  10. Recycling the dead

    Science News Explores

+ 8 more sources — see the full list on Lenz

Filed Under

Carbon CycleDecomposers

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