Replanting the Amazon could help save the world’s climate. Here’s why it’s so hard to do

Milton da Costa Junior nosed his pickup through a remote stretch of the western Brazilian Amazon to check on his babies. The nonprofit organization he works for, Rioterra, has planted millions of young trees in the rainforest as part of an effort to reforest woodland decimated by illegal logging and ranching in the area.

As the Toyota lumbered towards a ramshackle wooden bridge on the way back to the town of Machadinho d’Oeste in Rondônia state, Da Costa said two masked men on motorcycles sped past him, then blocked his way.

One of the men drew a revolver, Da Costa said, and delivered a message: Stop planting trees.

Local authorities said the September 2021 incident, which Da Costa outlined in a police report that was reviewed, is being investigated. No suspects have been identified.

Threats are just one of the challenges facing Rioterra and other environmental groups around the world pursuing a seemingly simple fix for the climate crisis: replanting denuded forests. These projects, science suggests, could help slow global warming by trapping carbon dioxide in living trees. Such efforts also could restore wildlife habitats and help protect threatened species. In the Amazon, it would also safeguard the atmospheric moisture that rolls off the rainforest and carries showers to faraway fields and reservoirs.

But in Brazil, many farmers who have carved livelihoods out of the rainforest fear that environmental groups want to push them out. Tree-planting groups, meanwhile, have struggled to cultivate some native trees on a mass scale. Seasonal flooding, fires – even arson – are perpetual worries.

Then there is money. Ecologists hope to protect the Amazon from a so-called tipping point – when so much land is cleared that the ecosystem can no longer sustain itself as rainforest and dries out into a degraded savanna. To do that, forest restoration needs to occur over a jungle area twice the size of Germany, according to Carlos Nobre, one of Brazil’s most prominent climate scientists. The price tag: more than $20 billion, he estimates.

Replanting efforts in Brazil so far are modest operations, albeit rapidly growing ones, led mainly by nonprofits. Out of dozens of reforestation initiatives in the country, Rioterra and The Black Jaguar Foundation, a Brazilian-European group, are among the largest. Rioterra has reforested Amazon land approaching the size of Manhattan over the past decade and plans to more than double that by 2030, said Alexis Bastos, who manages the nonprofit’s reforestation efforts and was one of its founders. Rioterra spends about 12 million reais ($2.4 million) annually on reforestation, he said.

Black Jaguar is even more ambitious: It hopes to spend at least $3.7 billion in the next 20 years restoring a forest area the size of Lebanon. Through corporate and private donors, it has raised just 0.2% of that sum so far and planted just 0.03% of its goal.

Meanwhile, Amazon destruction continues at a furious pace. Government data show that about three soccer fields’ worth of virgin forest was cleared every minute in 2022. Illegal invaders destroy in hours what it takes Rioterra or Black Jaguar a year to plant.

Still, scientists say that if reforestation is possible anywhere, it’s Brazil. The country has huge amounts of previously forested land ripe for restoration. Much of that could happen naturally if adjacent, intact jungle were simply allowed to reclaim the scarred patches. Brazil’s laws mandate a level of forest conservation unseen in most countries.

“Reforestation is really essential to save the planet,” said Nobre, the climate scientist. “We could do it. Are we going to do it? That is still a question we cannot answer.”

THE ACCIDENTAL CONSERVATIONIST

In Brazil, people have wrestled for centuries over the fate of the rainforest, a struggle that has pitted indigenous forest dwellers against European settlers and their descendants looking to tap its riches.

For most of that history, development won. Deforestation exploded in the 1970s as the ruling military dictatorship of that era encouraged people to settle the vast territory.

Among the migrants was Bastos, one of the founders of Rioterra, who arrived in Rondônia as a child in 1982. His family hoped to cash in on the government’s promise of free farmland. Instead, Bastos said, his father launched a furniture business in the city of Porto Velho catering to settlers arriving in droves.

Growing up, Bastos said, he was largely indifferent to the sound of chainsaws and the haze of smoke from ranchers burning trees for pasture. In his 20s, he discovered a passion for diving in Amazon waters. Amid electric eels and behemoth pirarucu fish, he was appalled to see that Rondônia’s Rio Preto, or Black River, had become an underwater junkyard of discarded refrigerators, car parts and beer cans.

He and his diving pals organised cleanups and events to raise awareness about human impacts on the Amazon. In 1999, Bastos and six friends, mostly fellow divers, founded the Rioterra Center for Cultural and Environmental Studies of the Amazon as a vehicle to secure funding for their volunteer efforts. Rioterra means “river earth” in English.

Their big break came in 2008 when state-owned oil company Petrobras awarded Rioterra a grant of 3.5 million reais (about $1.5 million at the time) to do some reforestation in Rondônia.

The group knew nothing about silviculture. The learning curve was steep, Bastos, now 49, recalled. “People come to the Amazon to cut trees, not to plant trees,” he said.

Successfully planting a tree requires teasing out the secrets of that specie’s life cycle. For Rioterra, the process starts in the Jamari National Forest, near the small municipality of Itapuã do Oeste in northern Rondônia. On satellite maps, Jamari stands out as a roughly 2,200-square-kilometer island of old-growth forest in a sea of deforestation. Barely touched for millennia, it boasts a riotous diversity of animals and plants.

Dejesus Aparecido Ramos, a former Rioterra worker, said he spotted wild pigs, tapirs and jaguars during his journeys there. But the nonprofit’s real quarry is about 900 so-called mother trees scattered in and around the forest. With permission from Brazil’s federal parks authority, Rioterra staffers harvest seeds from these mother trees and transport them to the organisation’s nursery in Itapuã do Oeste, where they are grown into saplings that can then be planted.

Rioterra takes special pains to nurture threatened trees, among them pink cedar, Amazonian cherry and muiracatiara, whose handsome orange-brown wood is coveted for designer flooring. Few of these rare trees have ever been cultivated outside the wild. Getting a seed from a castanheira, commonly known as the Brazil nut tree, to the sapling stage takes 18 months.

“People think all you have to do is plant, but it’s not just planting. There’s a lot of technique behind it,” Bastos said.

To date, Rioterra has planted some 7 million trees on more than 57 square kilometers (22 square miles) of land. The nonprofit plants trees on state-protected nature reserves as well as private land mostly owned by small farmers.

Brazil reduced reforestation funding in the early years of the administration of right-wing former President Jair Bolsonaro, who left office in January. His administration also froze the Amazon Fund, a government-created vehicle that since 2008 has spent 300 million reais ($60 million) – mostly provided by the governments of Norway and Germany – reforesting 317 square kilometers of rainforest.

A lawyer representing Bolsonaro did not respond to a request for comment.

Bolsonaro's successor, President Luiz Inácio Lula da Silva, quickly reopened the Amazon Fund. The Environment Ministry, in response to questions, said the government aims to expand economic incentives and technical assistance for reforestation and grow the market for seed and sapling production.

THE WANDERING DUTCHMAN

Black Jaguar’s origin story begins in the Middle East, where Dutch entrepreneur Ben Valks said he was making a good living selling water filtration systems out of the United Arab Emirates. He said he sold his firm in 2004 and decided to travel the world.

In 2007, he visited northern Pará state in Brazil’s Amazon with the notion of making a documentary about black jaguars, a rare mutation of the spotted variety that has been hit by habitat loss and poaching. A jaguar tracker led Valks past denuded jungle where the only animals he saw were grazing cows. Valks was troubled, and inspired: “I start to think, what’s my purpose?”

Valks spoke with Brazilian biologist Leandro Silveira, a jaguar expert who revealed his dream of creating a 2,600-kilometer-long wildlife corridor along the Araguaia River, which runs half the length of Brazil. There the big cats could roam free to find food and mates, Silveira said.

Valks saw the potential. He founded The Black Jaguar Foundation in 2011 and set about building an organization.

Now 52 and the full-time head of the foundation, Valks has raised more than 6 million euros ($6.4 million), mostly from corporate sponsors, according to Valks and the foundation’s annual reports. They include São Paulo-based Movida, a publicly traded rental car company, and Caixa, a state-owned Brazilian bank.

That’s a sliver of his $3.7 billion target. But it has been enough to hire 122 full-time staffers who have planted or regenerated 326 hectares (806 acres) of forest with native tree species in the Amazon and neighboring savanna. Valks’ long-term goal is to add 1.7 billion trees along the Araguaia River.

“I want to be a billionaire,” Valks told a group of staffers at a 2021 training held in Pará state near the waterway. “Not in money, but in trees.”

MEET THE NEIGHBORS

If cultivating wild trees is a tricky business, dealing with the Amazon’s human settlers is even more complex.

Worldwide, violence and threats are commonplace for environmentalists working to preserve wildlife and habitat. More than 200 are slain annually, according to the watchdog group Global Witness. Brazil in 2021 ranked No. 3 on its list, with 26 killed.

Rioterra suspended planting trees in the state-protected forest preserve where da Costa was threatened. Illegal logging and ranching have proliferated there.

Black Jaguar steers clear of trouble, too. Farmers hostile to their efforts aren’t pressed to participate.

Some growers are suspicious, but willing to listen, the nonprofits said. The reason: Brazilian environmental law.

A federal forest code, dictating how much forest land could legally be clearcut, had been on the books in some form since the 1930s, but was widely ignored in remote areas of the Amazon.

A 1996 revision stepped up protection for the Amazon by requiring that at least 80% of most properties in the region be preserved. Further changes in 2012 also waived fines and a ban on agricultural production against farmers who had illegally destroyed forest if they agreed to bring their holdings up to code by reforesting or buying virgin land for conservation.

Some environmentalists were furious about the amnesty, which remains in effect. Illegal destruction remains widespread, particularly on public lands.

Still, most large commercial farms have responded to the incentives to come clean. Banks are not allowed to give loans to farmers found in violation of the forest code, according to Brazil’s Central Bank. Likewise, major soybean traders in 2006 joined the government and civil society in a pact called the Amazon Soy Moratorium, which prohibits the commodities firms from buying from farms with recent deforestation.

The code requires Brazil’s farmers collectively to restore between 56,700 square kilometers and 181,700 square kilometers of forest, an area nearly as large as Syria, according to researchers at Brazil’s National Institute for Space Research. That legal requirement will go a long way towards helping Brazil meet its commitment to reforest 120,000 square kilometers by 2030 under its Paris Agreement climate target.

“Brazil is millions of miles ahead of the vast majority of other countries” in having a reforestation framework in place, said Cristina Banks-Leite, a tropical ecologist at Imperial College London.

Even so, Valks and Black Jaguar face a daunting task: The ecological corridor he dreams of building contains land held by more than 13,000 private owners in need of convincing.

He began in Santana do Araguaia, a city of about 45,000 people in Pará state, from where he had previously set out in search of the elusive black jaguar and saw a ravaged rainforest.

His first taker there was Marcos Mariani, a rare farmer who has been outspoken on environmental issues. When not raising soybeans and cattle on his family’s 577-square-kilometer operation in Santana do Araguaia, Mariani campaigned against paving additional roadways in the Amazon that would open new areas to deforestation.

Mariani said he was intrigued by Valks’ proposal. “I thought his idea was great and said we are interested in supporting anything related to conservation,” the farmer said.

The two signed a contract. Black Jaguar committed to build a tree nursery on Mariani’s property, provide all the technical know-how, and monitor the area for decades to ensure it regrows. The nonprofit ultimately planted saplings on 170 hectares along small streams on the property.

Word spread quickly that some do-gooder tree project had come to town, according to Tânia Irres, who works in Santana do Araguaia’s municipal environment department. She said some locals opined that an NGO founded by a foreigner must be out to wreck their livelihoods. Others figured that if outsiders were gifting saplings and labor, then why not take advantage?

“It’s a small town, everyone knows each other,” Irres said.

She helped connect Black Jaguar with a few more farmers, including Clovis and Regina Molke, soy growers and cattle ranchers looking to get right with environmental laws. Fans of Bolsonaro, the couple were initially skeptical of these environmentalists, but free trees were too tempting to pass up.

Black Jaguar said it planted 54,000 saplings on the Molke’s property between December 2020 and February 2021, then replanted some in 2022 that were lost in a flood. Fast-growing sombreiro trees are already standing 3.5 meters (11.5 feet) high.

“Who knows. In three years, I’ll come back here and see if the forest has closed with big, beautiful trees,” said Clovis, whose family owns farmland in multiple Brazilian states.

Such early wins led to deals with other farmers. In all, Black Jaguar has signed contracts with 26 farms and planted 326 hectares (806 acres) to date. The nonprofit aims for the next planting season, ending in April 2024, to be its biggest yet with an additional 500 hectares restored.

SCALING UP

Saving the Amazon means nurturing billions of trees across an area larger than most countries. Saving the planet means doing it several times over.

Slashing the use of fossil fuels is paramount in slowing global warming. But scientists say removing carbon dioxide already in the air is also essential to avoiding the worst fallout from climate change. And they broadly agree that trees are the cheapest and simplest way to sequester carbon.

Limiting global warming to 1.5 degrees Celsius – a target laid out in the Paris Agreement – could require up to 9.5 million square kilometers of additional forest to help reach net-zero greenhouse gas emissions by 2050, according to the United Nations’ top climate science panel. That’s about the size of the United States.

Brazil and neighboring Amazon countries could make or break those efforts. Roughly 18% of South America’s Amazon has been destroyed already. If that figure reaches 20% to 25% and climate change continues to worsen, climate scientist Nobre theorizes that the moist forest will dry out and become a degraded savanna, releasing a carbon bomb into the atmosphere. That threshold could be reached in two to three decades at the current rate of destruction.

Nobre estimates that, in addition to stopping deforestation, some 700,000 square kilometers in the southern Amazon would need restoration to ensure that a death spiral isn’t triggered. More than half of that area would naturally regenerate if left alone for nearby jungle to reclaim it, according to his rough calculations.

Rioterra and Black Jaguar use this approach when possible. On the Molke’s property, for example, in addition to 30 hectares actively planted by Black Jaguar, another 140 hectares have been left to passively regenerate. Black Jaguar helps nature by fencing off such areas to keep livestock out, and by removing invasive grasses that can choke off tree growth. Given a few years, wild animals and the wind will carry seeds from the neighboring forest that will grow unassisted.

PAYING THE TAB

In August 2019, fires surged in the Amazon rainforest. The world reacted with horror as images of soaring blazes dominated the news.

Bastos of Rioterra said private donors began to open their checkbooks.

The French company Reforest’Action, which matches funders with tree planting projects, put up 270,000 euros ($290,000) to sponsor nearly one square kilometer of Rioterra’s new planting in Rondônia. Later, two European nonprofits also stepped up. Geneva-based Aquaverde donated 315,000 Swiss francs ($347,000) to Rioterra. Belgium’s Tree-Nation added 90,000 euros ($97,000) to reforest the state-protected Rio Preto-Jacundá preserve.

Black Jaguar, too, has turned to corporate donors.

Brazilian car rental firm Movida in 2020 signed a deal with Black Jaguar to fund the planting of 1 million trees, then-Chief Executive Renato Franklin said. The program is funded in part by Movida customers, who have the option of paying 1.99 reais (40 cents) a day on their rental contracts to offset their carbon emissions.

By year-end 2022, Black Jaguar had planted around 250,000 trees as part of that partnership, which Movida is considering expanding after the first million trees are planted.

“Ben talks about 1 billion trees. We have to think big,” Franklin said.

Rioterra is also tapping the market for so-called carbon credits, which companies can purchase to offset their greenhouse gas emissions. The nonprofit last year launched a project to work with about 600 small farmers in Brazil to replant some 20 square kilometers with trees. Reforest’Action is handling the packaging and sale of the credits. French cosmetics maker L’Oreal confirmed that it is the largest investor, with more than $5 million in the venture.

Bastos sees carbon credits as the path to raise the vast sum of money that scientists like Nobre say is needed.

Whether these and other tree-planting programs can rescue the Amazon remains to be seen. Resistance in some places remains fierce.

Last September, Milton da Costa Junior got a call saying the Brazilian government’s fire monitoring website showed possible fires at Rioterra’s replanting projects in the Rio Preto-Jacundá state reserve, where the 41-year-old had been threatened at gunpoint a year earlier.

Additional planting had been on hold there since that encounter. Da Costa headed back to the site, where the young trees had been growing for more than a year. Flying a drone high above the plot, he saw staggering damage: 189 hectares were now a charred wasteland. Forest fires do not occur naturally in the lush Amazon, scientists say. A person had to have sparked the flame, Da Costa suspected.

As da Costa stood next to his pickup truck using the drone, at least two men hidden in the jungle along the roadway shouted at him.

“We told you not to come back here, or you’ll find out what you have coming,” one of the men shouted. “Keep it up and we’ll eliminate you.”

Da Costa stayed quiet. “This time I was scared,” he said, recounting the event. “My daughter was just born 20 days earlier.” Da Costa retrieved his drone, yelled that he was unarmed, got in his truck and drove away.

He has since returned several times to monitor regrowth in areas that escaped the flames, but always with a police escort. Local cops said the threats against da Costa are under investigation, as is the fire, which they suspect is the work of unidentified illegal land-grabbers.

While planting in the reserve remains suspended, Rioterra is pushing ahead in more secure areas. Next up is 3 square kilometres of restoration near a Rondônia hydroelectric dam.

Despite the threats, da Costa doesn’t want to back off. He says the stakes are too high.

“The way it is going, if there is no one with our conscience, one day you won’t have any more rivers, you won’t have any more forest, you won’t have these things to pass on to our children and grandchildren,” he said.