Preface.  Coal only formed once on Earth over hundreds of millions of years because they had lignin and cellulose that microbes hadn’t yet evolved to consume. Eventually they did, and today termites, cows and other creatures are able to digest cellulose and lignin by outsourcing the job to microbes in their guts.  But it is still such a  complex process that scientists haven’t been able to copy it, which is why cellulosic ethanol is still not commercial and takes more energy and money to make than is returned.

Coal is still forming today, but will take tens if not hundreds of millions of years to form again, in far smaller amounts than in the Carboniferous period since it is forming from peat rather than hundreds of billions of trees.

Peat accumulates in wet swamps at a rate of about 1 to 3 millimeters (0.04 to 0.12 inch) a year, taking 12-60,000 years to reach three meters (10 feet) thick. To transform this peat layer into coal will take a long time. First it must be buried in a volcanic eruption or by some other means to compress the peat 10-fold  and push the water out.  Then the transformation won’t really get cooking until the peat is buried 3 to 4 kilometers (1.9-2.5 miles) deep where the temperature is over 100°C (212°F ) to set off the chemical reactions that will transform it into coal by compressing it even further and transforming the plant lignin and cellulose into a geopolymer of concentrated carbon. The higher the temperature, the more energy the coal will contain, doubling from lignin, with about the energy of wood, to anthracite, and finally, over a very long time, transform into graphite.

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Financial Sense, Jore, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

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Krulwich R (2016) The Fantastically Strange Origin of Most Coal on Earth. The absence of the tiniest creature can shape the world in the biggest way. National Geographic.

This is a story about trees—very, very strange looking trees—and some microbes that failed to show up on time. Their non-appearance happened more than 300 million years ago, and what they didn’t do, or rather what happened because they weren’t there, shapes your life and mine.

All you have to do is walk the streets of Beijing or New Delhi or Mexico City: If there’s a smog-laden sky (and there usually is), all that dust blotting out the sun is there because of this story I’m going to tell (See the effect of burning coal in one of the world’s most polluted cities).

It begins, appropriately enough, in an ancient forest whose trees “would appear fantastic to us in their strangeness,” write Peter Ward and Joseph Kirschvink in their book A New History of Life.

Some of them were giants: 160 feet tall, with delicate fern-like leaves that sat on top of pencil-thin trunks. This was the age when plants were evolving, climbing higher and higher, using cellulose and a tough fiber called lignin to stay upright. Had you been there, you would have felt mouse-sized. These trees weren’t just odd looking. “One of their strangest traits was their very shallow root system,” write Ward and Kirschvink. “They grew tall and fell over quite easily.”

So imagine, then, these stands of towering, fern-like plants mostly growing in swamps. The air is warm and moist, and the land (Europe, the Americas, and Africa were at the time one continuous mass) is covered by billions of trees that are sucking carbon from the air, growing, aging, dying, falling, and releasing oxygen. This is a world littered with dead trees piling on top of each other.

But when those trees died, the bacteria, fungi, and other microbes that today would have chewed the dead wood into smaller and smaller bits were missing, or as Ward and Kirschvink put it, they “were not yet present.”

Bacteria existed, of course, but microbes that could ingest lignin and cellulose—the key wood-eaters—had yet to evolve. It’s a curious mismatch. Food to eat but no eaters to eat it. And so enormous loads of wood stayed whole. “Trees would fall and not decompose back,” write Ward and Kirschvink.

Instead, trunks and branches would fall on top of each other, and the weight of all that heavy wood would eventually compress those trees into peat and then, over time, into coal. Had those bacteria been around devouring wood, they’d have broken carbon bonds, releasing carbon and oxygen into the air, but instead the carbon stayed in the wood.

We’re talking about a spectacular amount of carbon. Biochemist Nick Lane guesses that the rate of coal formation back then was 600 times the normal rate. Ward and Kirschvink say that 90% of the coal we burn today comes from that single geological period, the Carboniferous period.

And therefore, in a just (and biologically aware) world coal miners everywhere would be doffing their helmets to salute the tardy arrival of those teeny earth creatures, the wood-eating bacteria. By not being there 350 million years ago, and by not arriving for another 60 million years, giant seams of black coal now warm us, light us, and muck up our atmosphere. Equal numbers of environmentalists might spend the day throwing darts at these little guys for showing up so late.

But enough of me talking about them. It’s time for you to take a close look at these amazing wood-eaters. They come in many forms, but I’m choosing microbes called Trichonympha because they’re so tiny, so squirmy, and so, well, crazily busy. They’re single-celled and can be found, yes, inside a termite gut. They look, says photographer Richard Howey (who studies them), like teardrops, or pears “wearing wigs.

I had thought wood-eaters would be mellow, sluggish and a little less clumped together. So I had questions. A web search brought me to Richard Howey in Wyoming, who has written about and photographed Trichonymphawritten about and photographed Trichonympha, and I asked him to take a look at the video so I could pepper him with questions. Which is what I did …

Me: Wow! This is crazy. So much motion!

Richard Howey: Yes, it looks almost like a game of bumper cars.

Me: So why are they so squished together?

RH: I’m not sure. I was really stunned [when you showed this to me]. It seems like Macy’s on Christmas Eve. [Pause.] I know they reproduce at an incredible rate.

Me: What do you mean? Are we watching them having sex?

RH: They might be [laughs]. Their reproductive process is incredibly complicated … [goes on to discuss mating types]

Me: But mostly they’re eating, right?

RH: Oh, definitely. You see those little white crystals jiggling around? Me: Yeah, those shiny, stonelike things? What are those?

RH: Those are little cellulose bits; the termite has chewed and shredded the wood, and now these bits have reached its intestines. The microbes scoop them up …

Me: And once they get them inside?

RH: They produce a dissolving agent that’s going to reduce those bits to starches and sugars that the termite can eat. Me: I like their little wiggly nose-like tops. RH: Those aren’t noses.

Me: Well, heads then …

RH: Actually … They’re kind of like legs. They have little locomotive hairs, flagella, attached there, and that’s how they propel.

Me: It’s weird. It looks like they know where they’re going …

RH: That’s an illusion. I think they just … go. Me: Why don’t they stop? Do they ever rest? RH: No, those flagella are very motile—they keep moving and moving and eating and eating …

Me: That’s it?

RH: That’s what they do. Always.

And we should be oh-so-thankful they do it. Because of them, dead trees get recycled. Soil gets replenished. Smaller organisms get fed. And miners can mine—which is only to say: Sometimes very little creatures make a very big difference.