Peatland carbon storage is stabilized against catastrophic release of carbon

November 2, 2011, American Chemical Society

Concerns that global warming may have a domino effect —unleashing 600 billion tons of carbon in vast expanses of peat in the Northern hemisphere and accelerating warming to disastrous proportions — may be less justified than previously thought. That's the conclusion of a new study on the topic in ACS' journal Environmental Science & Technology.

Christian Blodau and colleagues explain that peat bogs — wet deposits of partially decayed plants that are the source of gardeners' peat moss and fuel — hold about one-third of the world's carbon. Scientists have been concerned that might dry out the surface of peatlands, allowing the release into the atmosphere of carbon dioxide and methane (a greenhouse gas even more potent than carbon dioxide) produced from decaying organic matter. To see whether this catastrophic is a realistic possibility, the scientists conducted laboratory simulations studying the decomposition of wet bog peat for nearly two years.

Far from observing sudden releases of greenhouse gases, they found that carbon release and methane production slowed down considerably in deeply buried wet peat, most likely because deeper peat is shielded from exchange of water and gases with the atmosphere. In connection with previous work, the study concluded that "even under moderately changing climatic conditions," peatlands will continue to sequester, or isolate from the atmosphere, their huge deposits of and methane.

Explore further: Storage of greenhouse gasses in Siberian peat moor

More information: Experimental Burial Inhibits Methanogenesis and Anaerobic Decomposition in Water-Saturated Peats, Environ. Sci. Technol., Article ASAP. DOI: 10.1021/es201777u

A mechanistic understanding of carbon (C) sequestration and methane (CH4) production is of great interest due to the importance of these processes for the global C budget. Here we demonstrate experimentally, by means of column experiments, that burial of water saturated, anoxic bog peat leads to inactivation of anaerobic respiration and methanogenesis. This effect can be related to the slowness of diffusive transport of solutes and evolving energetic constraints on anaerobic respiration. Burial lowered decomposition constants in homogenized peat sand mixtures from about 10–5 to 10–7 yr–1, which is considerably slower than previously assumed, and methanogenesis slowed down in a similar manner. The latter effect could be related to acetoclastic methanogenesis approaching a minimum energy quantum of −25 kJ mol–1 (CH4). Given the robustness of hydraulic properties that locate the oxic–anoxic boundary near the peatland surface and constrain solute transport deeper into the peat, this effect has likely been critical for building the peatland C store and will continue supporting long-term C sequestration in northern peatlands even under moderately changing climatic conditions.

Related Stories

Storage of greenhouse gasses in Siberian peat moor

January 29, 2007

Wet peat moorlands form a sustainable storage place for the greenhouse gas carbon dioxide but are also a source of the much stronger greenhouse gas methane. According to Dutch researcher Wiebe Borren, peat moorlands will ...

Peatlands disappearance of concern

November 10, 2006

A report released Friday at a U.N. conference in Kenya indicates clearing peat lands threatens the world's ability to reduce carbon dioxide in the atmosphere.

Nitrogen rain makes bogs contribute to climate change

December 11, 2006

High levels of nitrogenous compounds can make bogs give off more carbon dioxide, thereby adding to the greenhouse effect. This has been shown by the plant ecologist Hakan Rydin in an article published this week in the Proceedings ...

Northern peatlands a misunderstood player in climate change

March 15, 2011

University of Alberta researchers have determined that the influence of northern peatlands on the prehistorical record of climate change has been over estimated, but the vast northern wetlands must still be watched closely ...

Recommended for you

How the Elwha dam removals changed the river's mouth

January 19, 2018

For decades, resource managers agreed that removing the two dams on the Elwha River would be a big win for the watershed as a whole and, in particular, for its anadromous trout and salmon. The dams sat on the river for more ...


Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Nov 02, 2011
We saw a large peat fire in the Arctic this year. I wonder if this is not a warning of what might come.

Perhaps the top layer of peat dries out, burns, and exposes the next layer down. I suppose that might be mitigated by rising ocean levels submerging peat.

Things are complicated....
1 / 5 (2) Nov 02, 2011
As methane is continually released to the atmosphere from such places as rice paddies, the ocean, every lake and stream, your front yard especially after a wet period, every landfill, pastureland etc., Where the hell is it all as the measured concentration is less than 5 ppB? Is the methane converted to CO2 and water when it reacts with Ozone in the atmosphere. We know the ozone is formed by the reaction of O2 and UV radiation. These are all natural reactions of chemistry and physics.
1 / 5 (9) Nov 02, 2011
Great news, but I don't know if I should believe it... the graph looks like a hockey stick... I've heard I should be on the lookout for that...
1 / 5 (1) Nov 02, 2011
1 / 5 (6) Nov 02, 2011
Scientists concerned that global warming might dry out the surface of peatlands

(Reality) is what is; . . .

(Models) are what we thought it would be;

(Computers Models that project the future) are a curse;

When computer projections are mistakenly used as a substitute for reality !

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
5 / 5 (2) Nov 02, 2011
(Computers Models that project the future) are a curse;
When computer projections are mistakenly used as a substitute for reality !
What's your alternative: Ouija boards?
5 / 5 (2) Nov 03, 2011
(Computers Models that project the future) are a curse;
When computer projections are mistakenly used as a substitute for reality !
What's your alternative: Ouija boards?

Naa he uses repulsive neutrons beamed out from his swolen brain.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.