We often assume that the Amazon tribes have remained unchanged since the dawn of time, but at least some of them are likely to be survivors of urban collapse.
Amazon has almost no natural stone, so all buildings will be constructed from perishable materials and, if abandoned, swiftly reduced to nothing by nature.
We only know the full extent of Mayan civilization because we found the ruined cities of stone in the middle of the jungle. The old Amazonians weren't able to build anything similar, because they lacked stone.
Amazonian civilizations might have disappeared entirely. Interestingly, there is a very ancient voyage record by a certain Francisco Orellana (to be precise: his companion Carvajal), who describes the Amazon as densely settled by organized kingdoms (e.g. having uniformed soldiers). His record was considered fanciful, because "well everyone knows that Amazon is one big rainforest", but it is being reevaluated as accurate.
Kind of wild to think that all these uncontacted tribes could actually be more like post-apocalyptic survivors rather than a glimpse at our distant neolithic past.
The same holds for most surviving hunter-gatherer groups across the world.
Survivorship bias in the extreme. The only survivors are ones in fringe habitats away from the best productive land. We have no view into the larger, richer, more complex cultures that were the norm back then.
They're not survivors any more than anybody else alive today. And their relatives are still on the best productive land, but assimilated into a different culture.
Their cultures are (more or less) survivors from a time when their mode of subsistence was the norm even on (most of) the best productive land. We know majority hunter-gatherer lifestyles have been incredibly diverse, but almost all detailed records deal with people on very marginal land that have all been influenced by industrial societies in more or less direct ways, because those were the only ones still available when people started recording them at least semi-properly. Our window into that past is more like a single discolored piece out of a huge intricate stained-glass window. Judging by the impact that indigenous societies and indigenous philosophy from the Americas had on contemporary European thought in the 18th century, it's not a stretch to assume that we've lost a ton of hard-won and almost irreplaceable data on what makes humans function as they do when part of a society and what alternatives to our modern societies work as well or possibly even better.
The histories often talk about empty or sparsely populated lands. Which in some cases is dramatically different to what archaeology tells us. Either the historians were lying, or the diseases spread faster than the explorers. The jungle will quickly claim abandoned settlements, in merely years.
This reminds me of something I heard archeologists discuss in the "Time Team" series I used to binge. I the UK, when the Roman Empire fell/collapsed, the populace didn't pick up and continue the Roman's tech (bath houses, currency, ...) but simply reverted to pre-roman tech of mud/wood/stone. They left the city to pick up farming again.
From what I've read, this is because the Romans didn't try to integrate the British people into Roman society, in contrast with many other societies they conquered. They kept the populace at an arm's length and lived in enclaves away from the hoi polloi, which meant that most people didn't really benefit that much from the "tech" until the Romans finally left; the monuments, buildings, and fortifications (including, famously, Hadrian's wall and the forum basilica) were used as quarries to extract building materials for what came after.
This applies to most of the American lore about “Indians” as well. The people that nearly all European descent settlers encountered were many generations on from an utter cataclysm of continental plagues that nearly eradicated them, and certainly destroyed what advanced civilization they had pre-Columbus.
The white people didn’t know they were devastating the native Americans, but they were super off-base to judge them as savages when it’s far more accurate to say that the natives who did contact and conflict with the young USA and Canada were more like post-nuclear-holocaust survivors.
I've been reading Indigenous Continent by Pekka Hämäläinen recently, I picked it up now that it is available as a paperback. The history is fascinating and I highly recommend it with the note that I'm ~1/3 of the way through.
Early on in the book he describes the rise of Cahokia and other Mississippian societies in America as tied to the climate in the medieval warm period. And how during the Little Ice age the priestly class could not create good conditions for agriculture, which undermined their power at a time when crops were failing and hunting became a dominant food source.
I initially came across this book due to a Reddit post about the author being a failed child prodigy. My first thought on seeing the table of contents was "damn, this book sounds racist". But it's actually a series of historical accounts in support of Native Americans and their history.
This looks... dubious. The starting point postulating that America was populated by people from the lost continent of Atlantis does not inspire confidence in this account's historical accuracy:
> An origin as a race in some specific place is more probable―most likely, in some region now under the Atlantic Ocean. ... A red-race civilization certainly developed around the north central Atlantic region on both sides of the ocean, and the geographical center of this was in what is now the Sargasso sea, in the middle of the Atlantic ocean, but where tradition on both sides of the ocean places the lost continent of Atlantis.
If they didn't have the weapons (and immunity) to fight them off, they were going to judge them like that no matter what. I seem to recall the story of the Spanish finding Tenochtitlan at its peak, and then destroying it.
> The white people didn’t know they were devastating the native Americans, but they were super off-base to judge them as savages when it’s far more accurate to say that the natives who did contact and conflict with the young USA and Canada were more like post-nuclear-holocaust survivors.
Odds are good they knew (thanksgiving is literally foundational american history, but the Wampanoag were near ended by the end of the century).
But “they’re just savages” makes it much easier to genocide them and steal their land than “they’re survivors of a civilisational collapse”. The US put significant effort in extirpating the tribes from their homelands and exterminating them, this labor was considered so important even the civil war did not stop it (the Long Walk of the Navajos started around the same time as the Siege of Atlanta and the displacement / forced marchs policy outlasted the civil war, the california genocide was basically an ongoing policy from the mid 1840s to the end of the boarding schools and eugenic policies — though most of the direct killing had been achieved by the turn of the century, …).
It's important not to leave out the fact the warfare was two-way. I mean this in an extramoral sense, not taking one "side" or another. It's just too easy to fall into the "settlers exterminating natives because they're in the way" narrative, when that's not what happened.
> It's important not to leave out the fact the warfare was two-way.
I’m pretty sure the Navajos did not send settlers and army on death marches. Nor did the tribes start massive programs of sterilisation, or child removal and cultural destruction. The US did that. The settlers did that. The first governor of California literally stated:
> a war of extermination will continue to be waged between the races until the indian race becomes extinct
Because settlers wanted the place, and natives were in the way. Or could be used for forced labour (see: Act for the Government and Protection of Indians 1850)
> It's just too easy to fall into the "settlers exterminating natives because they're in the way" narrative, when that's not what happened.
Isn’t it? Settlers took over land, and when tribes got inconvenient settlers moved to extermination and called in the army.
The US made a bunch of empty treaties and broke them just as fast, doing nothing or even encouraging the destruction of the lifestyle of numerous tribes.
> The first governor of California literally stated:
Yes, "between the races", not "against the Indians." Because in his eyes, at least some natives were as intent on driving them out as he was them.
> when tribes got inconvenient settlers moved to extermination
To be clear, "inconvenient" usually involved native conducting raids, massacres, rape, and enslavement. Of course, had the settlers not been settling their land, this would not have happened. But I don't think anyone today would see this as an acceptable response to migration. (And it wasn't, solely, the same sorts of low-level clashes were quite normal even before Europeans, who injected themselves into it.)
As a more extreme example, there's great books written about the Comanche empire. Indeed, if people had really seen things this way at the time, there wouldn't have been large numbers of natives assimilating into settler culture, nor would natives have allied with settlers against other natives continually even through the 1800s, when nobody could have argued that how the Americans would behave was unknown. "The settlers broke treaties" is true, but it's also true that natives broke treaties or made treaties that they had no authority to make in the first place, resulting in all sorts of disasters. The story of colonialist expansion in the US is not good vs evil.
> Yes, "between the races", not "against the Indians." Because in his eyes, at least some natives were as intent on driving them out as he was them.
An assertion borne by absolutely nothing at best, and made as the US had just conquered the state and were looking to "pacify" it and fill it with settlers, made by the then holder of ultimate power in the state. Making up "some natives" is clearly equivalent, go off queen.
> To be clear, "inconvenient" usually involved native conducting raids, massacres, rape, and enslavement.
Something the settlers also did routinely and extensively, but hey without an army it apparently doesn't matter.
> But I don't think anyone today would see this as an acceptable response to migration.
People seem to be reacting pretty favourably to Ukraine's response to the current russian "migration".
> The story of colonialist expansion in the US is not good vs evil.
You certainly seem very intent on justifying it through claims that the natives were not innocent so it was OK.
Nowhere did I say or suggest it was OK. I don't find looking at the past through a moralistic lens helps me understand it.
> People seem to be reacting pretty favourably to Ukraine's response to the current russian "migration".
The colonization of America much more closely resembled mass migration and then subsequent cultural conflicts than it did Russia's invasion of Ukraine. It didn't really resemble the latter at all.
> An assertion borne by absolutely nothing at best, and made as the US had just conquered the state and were looking to "pacify" it and fill it with settlers, made by the then holder of ultimate power in the state.
If you mean "conquering" California, you mean taking it from Mexico after the Mexican-American wars, California had already been subject to colonization efforts for almost a hundred years, but even so, I don't think speaking of the US federal government or the state government as "the holder of ultimate power" makes sense. Most people for a long time lived effectively free from any state control.
I mentioned the Comanche - it might be interesting to note that Comanche peaked in power just a decade prior to his term as governor, and they were in every meaningful sense militarily superior to the Americans, Mexicans, and surrounding native groups. They did not have a presence in California, but they're a good counterexample to the idea that natives just couldn't resist settlers - they rapidly acquired guns, horses, and often frankly superior skill in using them, which was frequently exercised. There's no doubt that settler encroachment and fundamentally incompatible ideas of civilization resulted in the pushing out and near-extinction of independent native communities, but it was by no means a sure, given thing. If native groups had united against the settlers and decided to get rid of them, they would have been wiped out.
Was it just migration or taking/stealing land that? If immigrants (or anyone else) today started building a town on some farmer's land violence would occur one way or another. Maybe the land was purchased from the native Americans and I just don't know it?
This almost implies that their civilisation failed of its own accord, rather than it collapsing because 90% of the population were wiped out by introduced plagues/epidemics.
When the entire field of archaeology experts calls someone out as a crank, you should really ask yourself if you have a good reason to know better than them.
Breaking new ground here with the sarcasm as well. If you have a substantive comment to make please do. I don't hate the guy but we have the amazing opportunity to have an actual conversation about facts through the internet, empty remarks aren't necessary here
I think you mean Graham Hancock. He has a couple of very interesting recent podcast appearances also, and was gonna do a debate with a mainstream archeologist (who unfortunately backed out for now due to health issues, but I hope it'll still take place at some point!)
Hancock is a charlatan of the worst sort. He knows the vast majority of what he says is a distortion of the truth at best, and completely fabricated nonsense at worst, yet continues to say it for the money and attention it has afforded him. There are so many strongly compelling pieces of contra-evidence that pretty thoroughly debunk literally all of his claims, yet absolutely nothing in way of any actual hard evidence that supports any of it.
His entire central thesis is essentially "Things are older than what scientific evidence suggest because I think this thing looks like that thing."
The ancient world is a fascinating place full of many rich cultures and interesting stories, and it doesn't need charlatans like Hancock making shit up to make it any more exciting.
Phrasing like 'Now businesses are attempting to capitalise on this ancient method ...' is true, but as others here have noted, this is not a new area of research, or a new area of business.
Can recommend "Burn - Using Fire to Cool the Earth" (2019) by Albert Bates & Kathleen Draper- which looks at various, often surprising, uses for biochar.
> Now there's growing interest in the lessons their methods may hold for societies today
I don't know how to tell this without being condescending, but do you guys even understand how farming works?
The fertile soil is a result of a long process of bringing organic material and ash and depositing it on the field. Exactly the opposite of what we are doing today
When they lived in the rainforest, they would gather whatever leftovers from eating, possibly their feces, decaying matter, and deposit it all on the field. They would keep hunting, they would keep gathering, and all that hunted and gathered material would end up on the field. Maybe they would compost it separately and then drop it on the field, maybe they would drop it on the field and the field would be in effect the composting area. Over hundreds or thousands of years this would create those amazingly fertile fields.
It is very easy to see how this developed. They probably have noticed that if they keep throwing their leftovers or feces in a particular area, everything starts growing better there. The same if you throw out ash. Which they had lots of beacuse they were burning a lot of wood every day, living in the rainforest and not facing energy price hikes. If you have a village and you hunt and gather every day, if you constantly keep burning wood fire and spread it all around your village for thousands of years -- guess what -- whether you planned it or not you will create those fields because I bet nobody would be trucking the garbage far from the village.
The problem is we do not live in the rainforest and we do not have so much organic matter to cover our fields. And the leftovers from what we eat we dump mostly into landfills. Our feces are also escaping the system and are not providing matter back to our fields.
In California, at least, yard waste and kitchen waste are diverted to composting facilities by law, and over half of biosolids (feces) are composted as well.
I imagine (hope!) that the rest of the world will follow. And it's not only about soil fertility. If this waste decomposes in a landfill, it becomes a major producer of methane, which is a potent greenhouse gas.
> imagine (hope!) that the rest of the world will follow.
Which world? The rest of the US? Composting and waste separation is common everywhere in the world. Sewage waste is more problematic as it contains heavy metals and microplastics, but at least in most developt countries very few of that reaches the ocean.
I am totally in favor of collecting organic matter separately and use it in agriculture but one thing I don't understand is this :
Whether it's in a landfill or a field, won't it produce methane just the same when it decomposes ?
No - anaerobic digestion produces more methane; aerobic digestion (lots of air mixed in) favors more CO2 and less methane. Typically, if you have a deliberately anaerobic industrial composting operation, you capture the methane and produce a small amount of power from it. But aerobic digestion is faster and is what I believe most big facilities use. There's still some methane but much less than if you threw the stuff in a landfill.
> I don't know how to tell this without being condescending, but do you guys even understand how farming works?
Not sure why you're being condescending when you're totally uninformed & wrong lol.
> The fertile soil is a result of a long process of bringing organic material and ash and depositing it on the field. Exactly the opposite of what we are doing today
2 minutes of research would tell you that the Terra Preta soil consists of
- tiny, broken pottery shards
- weathered charcoal
- bones/compost/manure
> It is very easy to see how this developed. They probably have noticed that if they keep throwing their leftovers or feces in a particular area, everything starts growing better there. The same if you throw out ash. Which they had lots of beacuse they were burning a lot of wood every day, living in the rainforest and not facing energy price hikes. If you have a village and you hunt and gather every day, if you constantly keep burning wood fire and spread it all around your village for thousands of years -- guess what -- whether you planned it or not you will create those fields because I bet nobody would be trucking the garbage far from the village.
The fact that you keep referring to them as hunter-gatherers when they've clearly developed an advanced fertilizer is hilariously absurd.
I think it would be better if you just red my comment more carefully.
Nowhere I called them "hunter-gatherers". That's something YOU wrote. You took words "hunter" and "gathered" and created in your mind "hunter-gatherer" which is completely different because it has a specific meaning.
People are still hunting and still gathering to this day. This does not make them hunter-gatherers. Hunter-gatherers describe a civilisation that is primarily concerned with hunting because they do not farm anything. These people were clearly farming, but farming does not exclude hunting or gathering.
The pottery, bones, compost and manure do not indicate advanced knowledge of farming. This just describes a dumping ground of a pre-industrial civilisation. That's pretty much all of the garbage they had. And they had to throw it somewhere and that somewhere was around them where the fields were.
I am not saying they didn't have any knowledge, but saying they had advanced knowledge is just jumping to conclusions.
Condescending on the original comment was because the authors could have asked any farmer and would get an explanation of what is happening.
Condescending on a response was because a guy didn't even bother to read my comment and was putting stuff in my mouth that I didn't say. And also because uses condescending language (like "hilariously absurd") when clearly wrong.
Do I think people should be nice to each other? Yeah, I do. But I also believe my self-imposed obligation to being nice to you is conditioned on you following minimum rules. I am not expecting much, really. Like don't say I wrote something which I did not. Or put a minimum effort when writing an article if you expect kind response. If you don't do it, I reserve my right to respond about it the way how I feel.
I believe requiring everybody to be nice to everybody else in every possible situation is not a good way to have an advanced civilisation. I think there was a Black Mirror episode to that effect.
> I think it would be better if you just red my comment more carefully.
> Nowhere I called them "hunter-gatherers". That's something YOU wrote. You took words "hunter" and "gathered" and created in your mind "hunter-gatherer" which is completely different because it has a specific meaning.
Someone who hunts and gathers every day is definitionally a hunter-gatherer, and vice versa. If you didn't mean to call them hunter-gatherers, then perhaps it's you who should be writing your comments more carefully.
> Nowhere I called them "hunter-gatherers". That's something YOU wrote. You took words "hunter" and "gathered" and created in your mind "hunter-gatherer" which is completely different because it has a specific meaning.
> Someone who hunts and gathers every day is definitionally a hunter-gatherer, and vice versa. If you didn't mean to call them hunter-gatherers, then perhaps it's you who should be writing your comments more carefully.
Orellana's voyage down the Amazon river is the subject of one episode of Michael Wood's Conquistadors, a series of travel videos linked below. Orellana described seeing large communities and cities from the river, recording the existence of a large population that had been decimated by the time the wider world ventured into the Amazon.
For laughs I one time gather a bunch of research (from the cutting edge to the practically applied) to do 1) large scale solar distillation for sea water desalination and for ethanol production. Think big arced mirrors focused on liquid salt tubes. 2) very large cannabis fields. If you water it it will grow in the desert without further aid. 3) yeast to turn the leaf materials into ethanol.
Apparently a tiny chunk of Sahara could make a serious dent in energy consumption. (One can of courses also use biomass to make biogas or solid fuel)
Yield is up to 1200 ton per square km. 205.2 ton ethanol per km2 (261 400 liter) 1 539 646 kwh/km2 If we use 100 000 000 barrels of oil per year 162 820 000 000 kwh The farm would be 0.1 million km2, the Sahara is 9.2 million km2, it would take little over 1%, say 2% US total farmland area is 3.6 million km2
Recycling yeast and chemicals gets much better at scale.
We know how to pump crude into container ships but oil is a dangerous substance. Ethanol doesn't require state of the art safety measures, it can just spill, the boats can just sink without horrific consequences. On the contrary.
The process on that scale leaves behind a lot of stuff that will have to be used for something. Seeds and seed oils are very valuable, hempcreed and bio plastics can be used for construction, can make fabrics, clothes, paper etc
One could also make solar biochar and enhance the soil. Hemp by it self enhances the soil. Add some compost and some bio char and you should be able to grow other things too.
The surprising thing to me was that there is a lot of ongoing research for each component of the plot. We kinda know how to do all of it but we also know very little, there is much to learn still.
I seriously doubt that except fresh produce in some hellishly hot desert country large scale agriculture using desalinated water makes sense. Much less so if you don't grow some cash crops but have to process it then transport the final product.
There are almost "miracle plants" like Salicornia which can be watered with sea water, but these do not have growth rates of more picky plants like corn or hemp.
It could be but doesn't have to be energy positive. You cant put sunlight into oil tankers but you can turn it into crops and make stuff from the crops (like ethanol)
"When he plunged the red and gold flag of Spain into the ground on the Paria Peninsula in Venezuela, it marked the beginning of a "great dying". It's been estimated that 56 million indigenous people were killed across the Americas by 1600 – so many, it cooled the Earth's climate."
Oh man,What a piece of bullisht! comming from what was a respected medium in the past like the BBC.
There are some people that believe that millions of people could have died because of the illnesses coming from Europe, that at the same time came Asia and Africa as they are united. To say that those people were killed on purpose is a piece of sht, and propaganda without proof.
Not to mention the 50 million that is absolutely outrageous. Not even the British and North Americans(now US and Canada)native extermination had such high numbers, and that was on purpose("the only good Indian is the dead Indian" founder's fathers quote) and using technology available in almost 20th century.
Spaniards and Portuguese in 1600s were very small numbers and technology was more advanced but not that much. They conquered South America with the help of native tribes, something that is well documented.
And the queen of Spain made native Indians that had baptised by law equal to Spaniards. Something that people in the USA only made in the middle of 20th century with Indians, Mexicans(from conquered territories like California) and black people.
I think you will find the numbers come from 1491 by Charles C. Mann, which is one of the books that kicked off a reexamination of the entire settlement by Europeans of North And South America, and which also goes into the reasons why the native population had little resistance to the European diseases. The climate change theories compete with Volcanic explanations, but there was certainly an impact, the great swarms of the now extinct passenger pigeon for example are believed to be due to the die off.
It wasn´t in some sense on purpose, smallpox blankets aside, the first contacts from Europe spread disease everywhere they went, mortality rates have been estimated at 90% or more. No coherent society survives that kind of event. Francisco de Orellana or somebody on his expedition probably carried the diseases that depopulated the Amazon, and led to it being empty when it was revisited..
And had that not happened. If the native population had been resistant to the new diseases, then the Europeans would have been thrown back, as the first US colonies seem to have been. The technological advantage was certainly there, but would have been impossible to sustain on a sea based invasion across an entire ocean at that time.
A genocide that was accidentally extra effective because you happened to be resistant to a different set of diseases to the other people is still a genocide. They the same playbook as the founding fathers did.
I think this proves that humans can be beneficial to their environment.
Much of what we think of as wild jungle actually isn't. The trees that grow in a jungle have faced selective pressure from animals and humans for thousands of years.
Humans are just better at it, because we garden.
In the case where humans were selecting, and planting trees that produced an edible fruit or nuts . (that also benefitted other animals) it changed the ecology of the forest.
That can't be true. Where Ants build their colonies, they also likely displace or destroy things that were in those places in the ground previously. Ant colonies can be huge. They can span miles.
They also will attack other insects and prey on them. They even sting humans.
And have been used by indigenous people to torture captured prisoners during their conflicts.
Let's say I have a small place in the country, with a vegetable patch and also a compost bin that I'm barely competent to operate. Maybe I also have access to chicken guano. And of course grass clippings, probably containing weeds too.
How do I leverage this to make biochar, and then how do I use the biochar to improve the vegetable patch ?
Making biochar is just heating bio-waste in a container to high temperature, but to not let it actually burn. Like making charcoal, but slightly smaller temperature. Biochar - bio-charcoal.
Make biochar, there are many guides on the interwebs.
Add continuously to you compost bin along with the normal stuff you put in there.
When the compost is done, add it to the garden.
Note the step of adding it to your compost, not to your soil directly.
The charcoal acts like a sponge for water soluble nutrients in the soil; if you add it to the soil directly, it will suck them out of the soil first, temporarily depleting it. Long term it acts as a reservoir, but you want it to go into your garden full.
Making diy biochar imho makes sense if you have dry, wood-ish material (Arundo, bamboo, branches). Otherwise you are likely to produce a lot of smoke for little biochar.
As for the garden organic waste one can tie itself in knots trying to balance this or that. In my experience shallow trench composting works just fine. You do not get a smelly pile leaking fluids, packs of slugs / swarms of flies. No extra work (mixing, distribution).
Earthworms will also thank you.
You may have issue with hardy weeds and rats, so you milage may vary.
One can ferment the weeds in a plastic bag before buring them lowering the chance of spouting, but this is extra and quite smelly work.
One can also dig deeper(+30cm of earth cover). Less chance of weeds and animals digging to snack on a rotten carrot.
From what I remember it was just a tease at the very end of the book (1491).
It seemed to be on the frontier of the research at the time the book was published. They knew about the existence of black earth (terra preta) but were really only speculating about how much human effort and over how much time was involved to create it.
Our volunteer group is creating new urban forests. Digging out invasives and planting natives.
Our soil is terrible. Glacial till (?) and gravel.
In addition to mulch and soil treatments, someone suggested transplanting some dirt from healthy forest areas. Maybe there's fungus, bacteria, or whatever, that will help our new plants. Couldn't hurt, right?
What struck me in the article was the description of re-vegetation from farmed species. I was just checking out the last 100 years of aerial photography here in Sydney and it was frankly shocking how much things have changed and reverted over time. Original forest, then totally denuded, then dense vegetation, then back again over few decades. In a tropical area such as the Amazon I'm sure that you could see a totally cleared area reclaimed by jungle at rates exceeding a meter a month, even a meter a week! One can really appreciate that they didn't build in stone for fun ... anything else would have disappeared the moment they took a break from weeding.
I still have an imaginary bet running with myself that we will eventually discover that Terra preta was the result of some form of pit roasting technique. Dig a hole in a different spot for each celebration.
What is the difference between biochar and charcoal? It would be good to hear what is physically different, as well as what is different in the process
Or jump straight to the science with a meta-analysis - "A global dataset of biochar application effects on crop yield, soil properties, and greenhouse gas emissions" - https://www.nature.com/articles/s41597-023-02867-9
Or the million Youtube vids etc.
Blah blah sequestering CO2, what I like is it's a permanent soil amender, your work in the garden lasts 100 years, plus it's a solution to all carbon rubbish. Not quite got grass clippings sorted yet, but trying to hack a solution. I'd love to know if a solar oven would work.
What is biochar exactly? I see some relationship with the Amazon Dark Earth in the OP - is it the same thing? Related?
EDIT: From the OP:
ADEs have up to 7.5 times more carbon within compared to the surrounding soils. As ADEs accumulate, the carbon becomes trapped underground, where it remains stable for hundreds of years – locking it away and delaying its entry into the atmosphere.
It's not clear why the carbon within ADEs behaves this way, but scientists suspect that it has something to do with "black carbon", also known as "biochar". This key ingredient is made from organic material that has been turned to almost pure carbon at high temperatures, in the presence of little oxygen. The process doesn't emit as much carbon dioxide as charcoal production, but leads to a fine, crumbly black product that has been found in ADEs across the Amazon.
So how much carbon does biochar release? What is the climate impact of it?
> Not quite got grass clippings sorted yet, but trying to hack a solution. I'd love to know if a solar oven would work.
This is awesome work! I hope you write up the results, and even Show HN.
Here is some information from one of the articles linked by the OP
The main technique to create biochar, called pyrolysis, involves charring waste vegetation at low temperatures in an environment with little to no oxygen. “If you starve it of oxygen, then you cannot oxidize a piece of wood to CO2 and water—and you leave a lot of carbon behind,” said Lehmann. The same piece of wood left to rot or burned in normal (oxygen-rich) conditions would release its carbon into the atmosphere within minutes to months. When vegetation is charred, the carbon remains trapped for decades or even centuries. ...
Recent research has found that biochar improves the soil in some contexts and has the most climate mitigation potential of any land-based effort, including agroforestry and afforestation—though Lehmann pointed out that nothing is more effective than keeping forests standing in the first place.
Biochar is charcoal that has been loaded with nutrients. The immense surface area of charcoal provides a concentration of nutrients and refuge for bacteria. I use it to reduce nutrient leaching over winter when we get several feet of rain.
Presumably, if a form of carbon in the soil is inert, then it doesn't do much to help agriculture, although it would be sequestering carbon. Organic matter in the soil will be normally be decomposed fairly quickly by soil bacteria and fungi, and these nutrients will be available to plants; dead plant matter then goes back onto the soil.
Edit: the Nature article linked above said "Biochar incorporation can increase crop yield by ameliorating soil physical structure, improving nutrient availability, and enhancing microbial activities"; whether it does this without decomposing, I'm unclear.
I believe there is also a nutrient capture/retention/release benefit from using biochar… it can keep beneficial compounds from washing away too quickly for a plant to make the most of it.
The biochar can be inert, while still providing a benefit.
wild guess here, but it's probably helping with drainage? much like you'd use perlite, moss, coir, etc. improving nutrient availability not by decomposition, but by facilitating movement of the nutrients
> So how much carbon does biochar release? What is the climate impact of it?
Biochar is carbon negative, it sequesters carbon.
Approximately ~ tree falls down, rots and it all gets turned back to methane -> CO2.
Instead you pyrolysis (burn in low oxygen) the tree, I use the cone dug in ground method. This releases part of the CO2 and also stores a lot of the carbon, as you partly can see when they study 10,000 year old campfires.
Then in theory you save on fertilizer and water as it averages it out and microbes process it better, which also reduces CO2. It also lowers compaction which makes for better plant root systems.
Our local government sewerage (which we are not on) gets turned to biochar and put in fields.
Biochar is a culture, it's beginnings are from the Amazon Dark Earth, I'm more into the science. People always have to talk about peeing on their biochar, sigh.... and they send their biochar off to be tested on how many football fields surface area per cubic inch ie one gram of biochar can have over 12,00 square feet of surface area. I'm not so sure on this, I think it's over maximization. Testing in the garden is good though, so I shouldn't complain.
Do you have room for a small compost pile? Or even a rotating compost bin? Grass clippings are a great add to a bin and they generate a good amount of heat to help the process get going.
Sorry if I was dismissive. Yes, it's fascinating, it's something I've been following for years, so I figured it was common knowledge.
Much more will be coming in the next years with LIDAR tech becoming wide spread. All great river basins in the world sprouted civilizations, why wouldn't the greatest river of all? It's just that it's easier to spot ancient constructions in the desert than beneath the foliage of the densest forest in the world.
https://en.wikipedia.org/wiki/Kuhikugu
https://en.wikipedia.org/wiki/Marajoara_culture
We often assume that the Amazon tribes have remained unchanged since the dawn of time, but at least some of them are likely to be survivors of urban collapse.