Dispatches: Re-Discovering Terra Preta in Amazonia

News and notes from Pacific Standard staff and contributors.
A deforested region of the Amazon.

For the upcoming May issue of Pacific Standard, staff writer Kate Wheeling traveled to Peru to report on a potentially groundbreaking new application of biochar, a soil amendment rich in carbon. Her feature, “The Great, Chaotic Biochar Experiment” will be made available exclusively to Premium members in the coming weeks. Until then, a behind-the-scenes look at an additional element of her story.

Picture the Amazon rainforest before Christopher Columbus kicked off centuries of exploration and exploitation of the Americas. Did you envision pristine wilderness, unmarred by human hands? For a long time, experts believed the pre-Columbian Americas were sparsely populated and pristine. The acidic soils of the jungle were thought to be too nutrient-poor to support anything more than small, tribal groups, which left little, if any, marks on the landscape. But evidence has been accumulating for some time that more people may have been living in the Americas during this time than in Europe. Some of the earliest was the discovery in the 1950s of pockets of a super-fertile soil dubbed terra preta, or dark earth, throughout the Amazon.

The black soil is a mix of charcoal, microorganisms, minerals, and ceramic shards—indicating that it was no environmental fortune, but a man-made substance. The punishing rains in the region typically wash the soil of nutrients, but many of the deposits of terra preta are hundreds or even thousands of years old, and are still rich in minerals.

Since then, archeologists have unearthed evidence of massive pre-Columbian civilizations in the Amazon that would have been utterly unsustainable given the natural impoverished state of soil in the region—and underneath them all, black soil brimming with broken ceramics. In other words, at one point, large-scale agriculture in the Amazon allowed vast societies to arise and thrive—at least until Europeans and their unfamiliar diseases arrived and wiped out, by some estimates, upwards of 90 percent of the indigenous populations. The use of terra preta was all but forgotten.

Its re-discovery is, in part, what inspired plant ecologist Brenton Ladd to work on a modern-day version of this soil stimulant called biochar. For the upcoming May issue of Pacific Standard, I followed Ladd around the Peruvian jungle for a few days as he attempted to re-introduce biochar to farmers there who, in the centuries since Europeans “discovered” the Americas, have become reliant on slash-and-burn practices, torching hundreds of thousands of acres of forest every year in pursuit of fertile soil. Ladd believes biochar can help break the cycle of poverty for Peruvian farmers, so they can leave what’s left of the Amazon intact.

The idea of a pristine, pre-Columbian Amazon untouched by man may be mostly a myth, but one thing still rings true. The massive Amazonian communities were nothing like modern-day metropolises in their environmental footprint. They rose up within the natural environment, rather than displacing it.

This dispatch originally appeared in The Lede, the weekly Pacific Standard email newsletter for premium members. The Lede gives premium members greater access to Pacific Standard stories, staff, and contributors in their inbox every week. While helping to support journalism in the public interest, members also receive a print magazine subscription, early access to feature stories, and access to an ad-free version of PSmag.com.

Related Posts