Jumat, 29 Juni 2012

Mushrooms may have stopped coal from forming 300 million years ago

Mushrooms may have stopped coal from forming 300 million years ago

  • Coal stopped forming 300 million years ago
  • Evolution of fungi that digest plants could be reason
  • Discovery could help in creation of new biofuels

By Rob Waugh

PUBLISHED: 07:37 EST, 29 June 2012 | UPDATED: 07:37 EST, 29 June 2012


Mottled bolete mushroom: The researchers believe that the evolution of early fungi may have stopped coal reserves from forming

Mottled bolete mushroom: The researchers believe that the evolution of early fungi may have stopped coal reserves from forming

The arrival of mushrooms may have stopped the formation of coal deposits we burn as fuel today.

This fuel is actually the fossilized remains of plants that lived from around 360 to 300 million years ago.

But at the end of that period, coal stooped forming.

Now scientists believe that the evolution of fungi that 'ate' dead plants may have stopped coal deposits from forming.

The discovery might pave the way for new biofuels.

The evolution of fungi capable of fully digesting plants may have stopped dead plants building up into peat, and then forming coal.

Coal generated nearly half of the roughly four trillion kilowatt-hours of electricity consumed in the United States in 2010, according to the U.S. Energy Information Administration.

The evidence, presented online in the June 29 edition of the journal Science, suggests that the evolution of fungi capable of breaking down the polymer lignin, which hel ps keep plant cell walls rigid, may have played a key role in ending the development of coal deposits.

With the arrival of the new fungi, dead plant matter could be completely broken down into its basic chemical components.

Instead of accumulating as peat, which eventually was transformed into coal, the great bulk of plant biomass decayed and was released into the atmosphere as carbon dioxide.

‘We're hoping this will get into the biology and geology textbooks,’ said Clark University biologist David Hibbett.

‘When you read about coal formation it's usually explained in terms of physical processes, and that the rate of coal deposition just crashed at the end of the Permo-Carboniferous. Why was that? There are various explanations.

'The evolution of white rot fungi could've been a factor â€" perhaps a major factor. Once you have white rot you can break down lignin, the major precursor of coal. So the evolution of white rot is a very important event in the evolution of carbon cycle.’

A fern preserved in coal: This fuel is actually the fossilized remains of plants that lived from around 360 to 300 million years ago

A fern preserved in coal: This fuel is actually the fossilized remains of plants that lived from around 360 to 300 million years ago

The evolution of fungi capable of fully digesting plants may have stopped dead plants building up into peat, and then forming coal

The evolution of fungi capable of fully digesting plants may have stopped dead plants building up into peat, and then forming coal


‘The concept of the invention of an enzyme that can break down the 'unbreakable' is really great,’ said Kenneth Nealson, of the University of Southern California.

‘The idea that a stable (inedible) form of organic carbon can become edible (and thus more difficult to bury over time), changes our perspective not only on global energy storage in the past, but on what it means for present day carbon sequestration and storage, in that sense this idea will have a big impact on our thinking about the past and the present.’

For their study, Hibbett and his colleagues focused on Basidiomycetes, which include mushroom species with the familiar cap-and-stem look that most people associate with fungi.

Basidiomycetes also include brown rot fungi such as the dry rot that can destroy houses by breaking down the cellulose in the construction wood but leave the lignin untouched and white rot fungi of interest to the pulp and paper indus tries that can break down both types of polymers.

The researchers then used molecular clock analyses to track the evolution of the enzymes back through the fungal lineages. The idea is that just as the hands of a clock move at a defined rate around the dial, genes accumulate mutations at a roughly constant rate.

This rate of change allows researchers to work backwards, estimating when two lineages last shared a common ancestor based on the amount of divergence.

The comparative analyses suggested that around 290 million years ago, right at the end of the Carboniferous period, a white rot fungal ancestor with the capacity to break down lignin appeared.

Prior to that ancestor, fungi did not have that ability and thus the lignin in plant matter was not degraded, allowing these lignin-rich residues to build up in soil over time.

 

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Or perhaps it was a major change in the oxygen levels in the atmosphere that changed the sizes of plants and animals! I just don't get the idea that the arrival of fungus only affected the largest plants. If the fungii was that virulent then it would destroy ALL the plants. It would have eaten all the plant vegetation because dead, rotting plant vegetation only comes in one size!!.

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Gummy Puppen, Cambridge, England, 29/6/2012 14:56 ... Unless fat Texans standing on the planet produces enough pressure to turn coal into oil naturally, what has Texas oil wells got to do with coal? Abiotic oil? Just did a quick bit of research, and it says that oil, gas, and coal are created in the mantle of the planet. Can you explain how a fern managed to get into the coal pictured above?

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On a timescale of 1 to 10 million years, who cares. We will be the coal.

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But at the end of that period, coal stooped forming. __________ Stooped?

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Really! Then why are some Texas oil wells replenishing? Why has Russia drilled into the Batholith. Try researching abiotic oil ...

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