- For thousands of years, Indigenous people in the Brazilian Amazon have used fire in their farming practices to preserve natural resources and regenerate the soil.
- But a rapidly changing climate and a drier forest have made these fires more difficult to control.
- In Xingu Indigenous Park, native people and researchers are developing alternative management methods to prevent uncontrolled burning, including removal of dry leaves and the use of less flammable plants.
- Drought has reduced the yield of traditional Indigenous crops like sweet potatoes and peanuts.
Since the beginning of time, Indigenous peoples have used signals from nature to guide their way of life. Their calendar is structured by the rhythm of plant growth or rains, which help them choose the best time to plant their crops. But things have changed in recent years.
“The climate has totally changed,” says Yakunã Ikpeng, chief of the Arayo village inside Brazil’s Xingu Indigenous Park. “The rains have been coming late and ending before the normal time. The ipê-amarelo” — Handroanthus chrysotrichus, or golden trumpet tree — “is dropping its flowers later and the cicadas are also singing late.”
Yakunã Ikpeng and his people have noticed that the world’s largest tropical forest is changing. The Amazon is less humid than it was in the past, affecting the climate in the region. Increased deforestation and the spread of urban areas into the forest have resulted in lighter and less frequent rains carried by the so-called flying rivers, the streams of water vapor that the rainforest trees release into the air.
In the past, this humidity helped to control fires, one of the main methods used by Indigenous people in the region for farming. Now it offers little protection against this danger.
The traditional farmers of the Xingu park, Brazil’s oldest Indigenous reserve, practice shifting agriculture. They cultivate different plots of land, moving every two years or so to allow the soil to recuperate and to preserve natural resources and biodiversity. To clear vegetation before planting, they use fire — an ancestral method passed down through the generations that helps to fertilize and aerate the soil. This favors the regeneration of useful plants in secondary forests.
“Despite being considered controversial by some, partial burning favors the accumulation of organic carbon, which is a natural fertilizer,” says forestry engineer Marcus Vinícius Schmidt, who has studied the sustainability of the Amazonian peoples’ farming systems for years. “And Indigenous people have methods for controlling the flames and keep them from spreading.”
Schmidt is the lead author of a recently published paper that looks at traditional forest management practices by Indigenous groups in the Brazilian Amazon. As in other parts of the world, the impacts of climate change on the Amazon have caused Indigenous people to adapt their traditional methods. This became evident in 2010, the year when the largest wildfire ever recorded in Xingu Indigenous Park burned nearly a tenth of its 2.6 million hectares (6.4 million acres). Since then, burns for planting that had previously been easy to control became harder to contain.
In the paper, Schmidt together with other Brazilian researchers and local Indigenous leaders, including Yakunã Ikpeng, assess how an initiative carried out by the Instituto Socioambiental (ISA, or Socioenvironmental Institute) is seeking to develop alternative forest management methods based on local knowledge and adapted to current conditions, aimed at forest regeneration.
“We focused on creating a local model based on Indigenous logic,” Schmidt says. “They are agricultural people with a great deal of knowledge about plants, different types of soil and the resilience of different environments. Our study showed how important it is to consider causes that could be leading to environmental degradation, and to think preventively instead of simply trying to invest in restoration methods based on different logic that doesn’t dialogue with local management.”
The ISA initiative, which began in 2016, tested new fire-prevention methods with the Ikpeng people of the villages of Moygo and Arayo, both located inside Xingu Indigenous Park. For example, fires were traditionally set during the hottest hours of the day, but this practice is no longer feasible. They determined that the best time of day to set fires is late afternoon, and that burns should never be left unsupervised.
“It’s essential to monitor fires these days,” says study co-author Katia Ono, a community spokeswoman and technical adviser in natural resource and fire management at the ISA.
Another tactic is the use of firebreaks. Before burning, leaves are swept away from the area to be planted so they don’t spread the fire. All organic material is removed, creating a void between the flames and the forest in case anything goes wrong. The sweeping also makes access to the areas easier in case there’s a need to put out a fire.
The Indigenous residents of the forest are also using more fire-resistant plants. One example is substitution of the grasses traditionally used to build thatched roofs, which themselves require periodic burning to renew their leaves. Less-flammable palm leaves have now been put into use for making these roofs, which also require no burning to grow, further reducing accidental fire risk.
Pequi and mango trees are also planted together with different yucca varieties to prevent growth of the grasses and form another barrier against spreading flames. While these methods haven’t been studied yet, they are known by locals to reduce fire hazard.
Even residents of the reserve who are not involved in agriculture know to be careful when it comes to fire. Indigenous Wauja, renowned for their pottery, historically let their kiln fires go out on their own. It was the same for others who would cook fish on river and lake banks. But today they’ve had to change their practices to protect the forest. Any sign of smoke or fire must be put out with water, Yakunã Ikpeng says.
“The younger generations don’t know the same forest that their grandparents did,” Ono adds.
Indigenous people have always lived with the certainty that their food would be provided by the soil. The list of the plants they grow is long: dozens of yucca species, peanuts, bananas, papayas, potatoes, yams, corn, cotton, and more.
“The Ikpeng have always been farmers. Their plantations have granted them access to more affordable food of better nutritional quality,” Schmidt says. “But with the local changes intensified by a drier climate, these systems are at risk.”
There’s concern that the soil may not be able to produce food in a drier Amazonian climate. “We have had only four months of rain so far this year,” Yakunã Ikpeng says. “And this isn’t enough to plant. The roots of the sweet potato and peanut dry up. And the banana also doesn’t do well.”
The changes to the climate, driven largely by the demands of urban people, are forcing Indigenous people to adapt to new times and to a less humid forest very different than the one their ancestors lived in.
“Nature has to be studied all over again. And this knowledge base continues to depend on the relationship between different generations,” Ono says. “Part of our work is also to make sure this happens.”
Schmidt, M. V., Ikpeng, Y. U., Kayabi, T., Sanches, R. A., Ono, K. Y., & Adams, C. (2021). Indigenous knowledge and forest succession management in the Brazilian Amazon: Contributions to reforestation of degraded areas. Frontiers in Forests and Global Change, 4. doi:10.3389/ffgc.2021.605925
Banner image of an Ikpeng Indigenous man managing a firebreak in Rawo Ikpeng village, in Brazil’s Xingu Indigenous Park. Image by Pytha Ikpeng.