Forests managed by Indigenous peoples and other local communities in the Amazon region draw vast amounts of planet-warming carbon dioxide out of the atmosphere while the rest of the rainforest has become a net source of the greenhouse gas, a new report has found. 

The discrepancy results from differences in deforestation rates between the two types of land. 

The study from the World Resources Institute, a nonprofit global research organization focused on solving environmental challenges, adds to a growing body of evidence showing that land held by Native peoples and other local communities around the world has better environmental outcomes than government and privately owned land.

The WRI study, published on Jan. 6, marks the first time researchers have quantified the forest carbon benefits of Indigenous territories and land stewarded by local communities in the Amazon region, which spans Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela. 

From 2001 to 2021, forested areas in the Amazon managed by Indigenous communities removed about 340 million more metric tons of carbon from the air each year than they emitted, an amount equivalent to the annual carbon emissions of the states of California and Massachusetts combined. Land managed by other local communities had similar outcomes, researchers found.

All other forested land in the Amazon region was a net source of carbon over the same time period because of high rates of forest loss.

While the main contributors to planetary warming are greenhouse gases released from the burning of fossil fuels, forests can also become a source of carbon dioxide emissions. Trees store carbon dioxide within their leaves, branches, trunks and roots. When they are destroyed through fires or clear-cutting, once-sequestered carbon is released into the atmosphere. In the Amazon region, drivers of deforestation include development from industrial agriculture, cattle ranches, mining, oil extraction and other activities, both legal and illegal.

The WRI report’s findings add an exclamation point to the evidence that Indigenous peoples and local communities are a major force in preserving the Amazon rainforest amid the rapid deforestation on land held privately or by governments.

According to Peter Veit, a co-author of the report and the director of WRI’s Land and Resource Rights Initiative, about 17 to 18 percent of the Amazon has been deforested in the last 50 years. Scientists estimate that once those levels get to 20 to 25 percent, the rainforest will hit an irreversible tipping point from which the region will transform into grasslands and savannah. The change would result in the release of an estimated 123 billion tons of carbon into the atmosphere, kill off thousands of plant and animal species and wipe out hundreds of distinct human cultures tied to the rainforest.

“We are very close to that tipping point,” Veit said. 

The WRI report comes as land not just in the Amazon region but throughout the world is under increasing pressure for food production, resource extraction and other demands linked to human population growth. 

About half of Earth’s land is stewarded by Indigenous and other local communities. Many of those groups have insecure land tenure, making them vulnerable to land theft, appropriation and related violence. Each year, about 200 land defenders, including many Indigenous people, are killed, although that estimate is widely considered an undercount. 

Veit suggests that governments can support Indigenous and local communities in protecting their territories by integrating their efforts into national climate plans, giving them secure title to their land and increasing direct funding to those communities. 

“We’re showing one of many reasons that forests controlled by Indigenous peoples should be valued,” said David Gibbs, a researcher at Global Forest Watch and a co-author of the report. The research, he said, “adds to the list of reasons that we already have to help protect those communities.” 

The Benefits of Local and Indigenous Control

In general, Indigenous peoples and local communities manage their land in a sustainable way based on customs and cultural values that are intertwined with the forest. 

“For Indigenous people and other communities, their land is a primary source of food, medicine, fuelwood and construction materials, as well as employment, income, welfare, security, culture and spirituality,” the report notes. 

That interdependence with intact forests creates an incentive for communities to sustainably manage their lands, Veit says. 

If left alone, most of those communities would continue to live as they have for hundreds of years. But they are increasingly under threat from outside pressures like legal and illegal mining, logging and agriculture, he said. 

While all forest in the Amazon region both stores and emits carbon, Indigenous lands capture more carbon than they emit each year when the entirety of that flux is considered. Veit and Gibbs said their analysis identified which Indigenous territories have higher carbon emissions and found that those communities may face greater pressures from resource extraction.

In Brazil, home to the greatest portion of the Amazon rainforest, the Indigenous communities in forests with the greatest carbon emissions are located in the country’s southeast, an area known as the “arc of deforestation.” In Peru, Indigenous lands that were net sources of carbon were located in regions dominated by gold mining. 

Of all the ways that governments can help communities defend their forestland from incursions that could increase the carbon emissions, Veit said that providing them with secure land title is the most important. 

In Brazil, the demarcation and formal titling of Indigenous peoples’ land stopped under former President Jair Bolsonaro’s administration, which held power from 2019 to 2022. Bolsonaro also defunded governmental agencies tasked with enforcing the rights of Indigenous peoples. Over the course of his presidency, deforestation rates in the country surged.

While obtaining legal title to land is important, the type of legal title communities obtain also makes a difference in their ability to defend their land from incursions by resource extraction and agricultural interests.

In most Amazonian countries, national governments reserve ownership of material that lies below the surface of the land, making it easier for them to grant companies licenses for mining and other extractive activities. 

“When you get security of land, you don’t get security like we do in the United States of all subsurface rights,” Veit said. “Your rights in the Amazon extend 10 inches below the surface and that’s it.” 

Veit has done research comparing the legal authority granted to extractive companies through means such as mining concessions with the legal rights given to landowners like Indigenous communities. 

“They don’t compare,” he said. “The natural resource rights holders have tremendous power to go onto and use land.” Human rights experts have advocated for communities’ gaining greater control over their territories and a right of refusal when governments and businesses seek to engage in resource extraction on or near their land. 

“Many governments around the world still view themselves as the best holders of common property rights to resources,” Veit said. “It’s ridiculous. There’s a real mistrust that communities can manage these important resources despite the evidence that shows that they can.” 

Amazon Emissions in Flux

The WRI report is based in part on a 2021 study in the journal Nature Climate Change that offers one of the best estimates of how much carbon dioxide was emitted by forests and how much they removed from the atmosphere globally in the last 20 years. The paper concluded that, during the 2001 to 2019 study period, forests sequestered about twice as much as they emitted each year—storing about 7.6 billion metric tons per year, or 1.5 times more than the United States emits annually.

The Amazon is a big part of that global equation, but the international team of authors acknowledged in their opening paragraphs how challenging the measurements are at global and regional scales. Emissions and absorption can take place simultaneously within regions, depending on when and where the forests are disturbed and managed, they wrote. 

The carbon fluxes, as scientists call them, also have high seasonal variability, and it’s not easy to distinguish between natural fluctuations and those caused by disturbances like fires and logging. All of that makes it hard to reproduce them in global climate models, although measuring them accurately is “increasingly important for climate policy,” the paper noted.

The scientists found that during the study period, forests in the Brazilian Amazon were a net source of .22 gigatons of carbon dioxide emissions per year but that the forests spanning all nine countries of the greater Amazon River basin (526 million hectares) were a net carbon sink, taking up .10 gigatons of carbon dioxide. By contrast, they noted, the net sink in forests of Africa’s Congo River basin (298 million hectares) was approximately six times stronger than in the Amazon basin.

The main reason is the far lower rate of human disturbance in the Congo River forests, Gibbs said. 

For the new analysis of the Amazon, Gibbs said the team used detailed Indigenous land mapping from the WRI’s LandMark project, which maintains detailed data about where Indigenous communities live and what their boundaries are as well as whether the boundaries are legally recognized by their countries. 

“We can basically put that on top of a map of forest carbon emissions, removals and basically add up what’s going on inside Indigenous lands and Indigenously controlled lands, and outside,” he said. From that, Gibbs said, the analysts were able to “decisively” conclude that “Indigenous lands in the Amazon are very strongly net carbon sinks.”

”There are already a lot of reasons that the world should support Indigenous people, and this, I would say, is one more very clear reason for doing that,” he concludes. “We have specific numbers, specific estimates that say these are some of the carbon benefits of what Indigenous people are doing for the world in terms of mitigating climate change.”