Question 18
Read the following article and answer the given subquestions.
Indigenous People May Have Created the Amazon’s ‘Dark Earth’ on Purpose
Indigenous people in the Amazon may have been deliberately creating fertile soil for farming for thousands of years. At archaeological sites across the Amazon River basin, mysterious patches of unusually fertile soil dot the landscape. Scientists have long debated the origin of this “dark earth,” which is darker in color than surrounding soils and richer in carbon. Now, researchers have shown that the indigenous Kuikuro people in southeastern Brazil intentionally create similar soil around their villages. [Edit i] The finding, presented December 16 at the American Geophysical Union meeting, adds evidence to the idea that the Amazonians deliberately manufactured such soil long-ago. [Edit ii] In doing so, these early inhabitants may have inadvertently stored massive quantities of carbon in the soil, says study presenter Taylor Perron, an earth scientist at MIT. [Edit iii] The technique, he says, could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils, helping fight climate change.
The Western world has long viewed the Amazon as a vast wilderness that was relatively untouched before the Europeans showed up. At the center of this argument is the idea that the Amazon’s soil, which is poor in nutrients, precluded its inhabitants from developing agriculture at a scale required to support complex societies. But a slew of archeological finds in recent decades — including the discovery of ancient urban centers in Amazonian areas of modern-day Bolivia — has revealed that people were actively shaping the Amazon for thousands of years before the arrival of the Europeans. Perron and his colleagues reviewed interviews of the Kuikuro people conducted by a Kuikuro filmmaker in 2018. Those conversations revealed that the Kuikuro villagers actively make dark earth — eegepe in Kuikuro — using ash, food scraps and controlled burns. “When you plant where there is no eegepe, the soil is weak,” explained the elder Kanu Kuikuro in one of the interviews. “That is why we throw the ash, manioc peelings and manioc pulp.” [Edit iv] The team found “striking similarities” between dark earth samples from ancient and modern sites, says Perron. Both were far less acidic than surrounding soils — probably thanks to the neutralizing effect of ash — and contained higher levels of plant-friendly nutrients.
These analyses also revealed that dark earth holds twice the amount of carbon as surrounding soils on average. The technique highlights how the ancient people were able to thrive in the Amazon by developing sustainable farming that doubled as a carbon-sequestration technique. With more and more greenhouse gases entering the atmosphere, making dark earth — or something like it — could be a method of mitigating climate change while supporting agriculture in the tropics. “People in the ancient past figured out a way to store lots of carbon for hundreds or even thousands of years,” Perron says. “Maybe we can learn something from that.” Adapted from: Kreier, Freda. “Indigenous People May Have Created the Amazon’s ‘Dark Earth’ on Purpose.” Science News, 05 Jan, 2023, https://www.sciencenews.org/article/indigenous-people-created- amazon-dark-earth.
Punctuate the sentence marked in bold as [Edit iii] correctly to improve the article.
[Edit iii] The technique, he says, could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils, helping fight climate change.
“The technique, he says, could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils, helping fight climate change.”
“The technique he says could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils, helping fight climate change.”
“The technique,” he says, “could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils, helping fight climate change.”
“The technique,” he says could provide a blueprint for developing methods of sustainably locking atmospheric carbon in tropical soils helping fight climate change.”