The Munduruku indigenous people are resisting hydroelectric dams on the Tapajós River, a major Amazon tributary. The hydropower, touted as green, would destroy forests - and could even increase greenhouse gas emissions.
Indigenous leader Geraldo Krixi Munduruku has problems sleeping at night. At 58, he feels again the fear he knew in 1989, when he had heard about the construction of a hydropower dam on the Tapajós River in the Brazilian state of Para for the first time.
Nearly 25 years later, the days of calm for the Munduruku community living on the Tapajós, surrounded by the Amazon forest, are gone. The Brazilian government plans to begin building the hydropower facility São Luiz do Tapajós in 2016.
Since Krixi has learned about this, his community has organized resistance to stop the project.
"The river, as well as the forest, is like our mother. If the Tapajós is dammed, how are we going to survive? Where would we go?" asks Krixi.
Not only the Munduruku would suffer if the dam were to be built - an area the size of New York City would be inundated, including the plant and animal species living there. Effects would reverberate throughout the ecosystem.
Meanwhile, open questions remain over climate impacts around the dam complex.
Still no land title
The Munduruku people, spread in villages along the Tapajós, have for centuries struggled for official demarcation of the Sawré Muybu Indigenous Territory, which encompasses an area of 178,000 hectares.
The Brazilian constitution guarantees permanent ownership of the lands traditionally occupied by indigenous peoples - as well as the exclusive use of soil resources, rivers and lakes within the area.
But the territory inhabited by the Munduruku at this part of Brazil's Pará state has not yet been recognized by the federal government.
With the threat of being flooded by the planned dam, indigenous leaders started to demarcate the land themselves. The Daje Kapap Eipi village has just erected a demarcation sign, very similar to the official one. "Whoever comes here and sees this sign will know this piece of land belongs to us, the Mundurukus," says Krixi.
The Tapajós River still flows freely along 800 kilometers (500 miles) in Brazil's Mato Grosso, Amazonas and Para states. According to the latest plan presented by the Brazilian Energy Research Company (EPE), seven dams are planned to be built on the Tapajós basin by 2024.
The Munduruku people were never consulted about the construction of dams. Groups like Greenpeace have sought to support their resistance - also due to the ecological value of the site.
"It is an unnecessary and incredible destructive project," said Bunny McDiarmid, co-executive director of Greenpeace International, during a visit to the region.
The dam would inundate thriving ecosystems, including critical habitat for animals such as the ocelot, howler monkey and pink river dolphin, along with numerous bird, lizard and amphibian species. More than 300 species of fish in the region could be impacted.
Infrastructure around dam construction also contributes to deforestation, as it allows access for logging, livestock ranching and agri-business.
Paulo Adário, a consultant and one of the founders of Greenpeace Brazil, says there is no room for projects, which "bring environmental impacts like deforestation or those which go against the right of traditional people."
Greenpeace also points out that although hydroelectricity is climate-friendly in the sense that it doesn't involve the burning of fossil fuels, studies have shown that dams - especially in the tropics - release a large amount of methane, a powerful greenhouse gas. This is due to rotting vegetation in flooded areas.
In addition, Greenpeace points out that the crippling droughts affecting some regions of Brazil recently could make the dams ineffective.
Adário points to a scientific Greenpeace study showing that the country's energy demand could be supplied by a combination of renewable and less destructive energy sources such as wind, solar and biomass.
Energy for development
Brazil's Ministry of Mines and Energy argues that the hydropower is important for the country's development. The ministry says that "modern hydroelectric projects are characterized by the respect for the environment and local populations."
"They also define plans for environmental and social compensation, improvements to the local communities, and commitment to international protocols," the statement continues.
The power plant would make another plan of Brazil's transportation and agriculture ministries possible: to develop a waterway to transport grain production from Mato Grosso state to Asia through the Panama Canal. Mato Grosso is the largest soybean producer in Brazil, and its main buyer is China.
But for now, the construction of São Luiz do Tapajós - which would have around 8,000 megawatts of installed electricity generation capacity - may not begin. The Brazilian Institute of Environment and Natural Resources (Ibama) has suspended the environmental license, saying that it will wait for a final assessment by the National Indigenous Foundation (Funai).
So the fate of the Tapajós - and therefore of the Munduruku - will depend on decisions from the capital Brasilia.
Jeremy Campbell, a professor at the Roger Williams University in Rhode Island, is impressed with the strength of the Munduruku people. Once known as warriors who used to decapitate their enemies, they were seen by Europeans for the first time in mid-1700s.
Campbell has been doing research in the Tapajós region since 1999, when he witnessed violence and intimidation during a time of explosive land-grabbing. He called the Munduruku "an incredible united people."
"They are a warrior people, and they say they are at war because their entire way of life is threatened," Campbell told DW.
"If the dam is built, they will not longer be able to live in a traditional way," says Campbell - which is something they will never accept, he believes.
Antonio Dace Munduruku, 28 years old, is one of the villagers who has traveled to Brasilia to fight in what he called a "modern-day war."
"People who live in the capitals and rich countries look at the Amazon as an empty place, as green area only. And everyone wants a piece of it," he says.
The father of two children, Dace says he wants his family to continue to live in their indigenous way. "Many people talk about climate and the role of forests - but we are the people who really preserve the forest," Dace concluded.