Bioc

For 80 leagues of riverbeds (more than 240 miles) the towns and villages stood so close together that there was not usually more than a crossbow shot between them … there were many roads and very fine highways … there were great quantities of food.

- Gaspar De Carvaja, 1541, on the Amazon River.

Just a Legend?

From Gaspar De Carvajal, who accompanied Francisco de Orellana on his voyage across the Amazon rainforest, this account continues to describe an immensely sophisticated civilization. He describes great cities, massive infrastructure projects, centralized states, complex socio-political systems of governance, and enormous swaths of land dedicated to agriculture. He paints a picture far different from that of the Amazon today. His odyssey was the first time Europeans traversed the Amazon River and happened early enough that it was before the smallpox pandemics that ravaged indigenous populations of the Americas had made their impact.?

Explorers and anthropologists who visited the Amazon later in history, post-pandemic, assumed that due to the lack of massive populations of people, he had either been making it up or greatly exaggerating. Many point to the poor quality of the soil as proof that a civilization, millions of people strong, could have never been sustained. But new evidence is telling a different story.

Increasingly, researchers are discovering more and more evidence, from irrigation grids to architecture, all reclaimed by the jungle that the region was vastly more developed than originally thought. But the question still remains, how did they feed themselves? It is a question not so different from the one we are beginning to face today. Decades of industrial agriculture, artificial fertilizers, and a changing climate have eroded our topsoil, and farmers worldwide are facing diminishing returns on their yields.?

Sustaining El Dorado

Ironically, given the immense growth of the Amazon Rainforest, the soil is actually of very poor quality when it comes to agriculture. It is almost impossible to grow anything at scale. Recently, a discovery has finally answered the paradox, and it holds promise to answer our own - Amazonian Dark Earth, or as modern scientists would call it: Biochar.

Researchers are beginning to find areas in the Amazon where the soil is very different from the natural, poor soil of the Amazon. These areas range in size from under an acre to hundreds of acres. The soil found here is extremely rich, dark in color, but most importantly, man-made. The secret to biochar’s richness and its color is simply charcoal. Biochar is when charcoal is buried in and mixed with soil, it is extremely porous, and microscopic passageways run through it within its pores. It is so porous that one gram of charcoal - the size of a pencil tip eraser has more than 9,000 square feet of surface area!

That is where the benefit is found in charcoal. Outside of being made of carbon, the porous nature of charcoal acts as a sponge that absorbs and stores nutrients and water, becoming a reservoir for the crops to take from as needed. With the ability to store nutrients, they are not washed away in the rain, meaning that chemical fertilizers are not needed. As if that isn’t cool enough, the pores also offer refuge for fungi and other microorganisms that the plants, especially their roots, rely on through a range of symbiotic relationships. The increase in the number of microorganisms and their biodiversity results in stronger, healthier, faster-growing, and higher-yielding agriculture.?

Lessons From a Lost History

Biochar is how Amazonian civilizations sustained themselves, and it will play an integral role in how our civilization sustains itself through the Anthropocene. Biochar is not only a way to bolster our agricultural yields, but when created correctly - it is carbon negative. Plants were grown to be converted into biochar sequester carbon. The burning of these plants to create charcoal can generate electricity or heat, and when done correctly, the CO2 from the burn can be captured on-site and put back into the soil, creating a circular lifecycle. The remaining charcoal is then sold to farmers, where it helps create larger and higher-yielding plants, which in turn sequester more carbon. Not only is this possible, but it is profitable!

Creating charcoal at an industrial scale is a carbon-negative, profit-turning business. But the scale does not have to be industrial; charcoal creation is easily made on smaller scales. Subsistence farmers and hobby gardeners can make a difference in their yields and carbon footprint by creating their own charcoal. Biochar can be made from ash leftover from bonfires, wood stoves, and fireplaces as well - mitigating, or in some cases even eliminating the carbon footprint of those midsummer bonfires or cold winter nights by the fire. Biochar is one of many amazing and innovative technologies offering real, tangible, and even profitable solutions to the climate crisis.??

Do you think Biochar is a feasible, large-scale solution to top-soil depletion and chemical agriculture? Vote here