A vast soy bean field in in Campo Novo do Parecis, in Mato Grosso state, Brazil. The 'Ferrograo' is a controversial project of construction of a trans-Amazonian train in Brazil to speed up its huge grain exports.

With his feather headdress and body paint, chief Beppronti Mekragnotire doesn't seem to have much in common with trucker Sergio Sorresino, but they share a cause: neither wants a railroad built across the Amazon rainforest.

Biding his time inside his big rig as he sat at a roadblock outside the town of Novo Progresso, in northern Brazil, Sorresino appeared to have every reason to resent Mekragnotire.

Because of the Kayapo indigenous chief and his warriors, Sorresino and thousands of other truckers were stuck on this stretch of highway BR-163, the road linking Brazil's central-western agricultural heartland to the river ports of the Amazon and its tributaries.

Clutching bows, arrows and spears, dozens of Kayapo blocked the road in protest on August 17, demanding the government abandon its plans to build the "Ferrograo," or Grain Railway, across the world's biggest rainforest—one on a long list of grievances against far-right President Jair Bolsonaro's administration.

The protest—since suspended pending a court ruling on their demands—obstructed truckers like Sorresino on and off for days, but he didn't seem to mind: he also dislikes the railroad , which threatens his livelihood.

"It's their right. The Ferrograo would hurt us, too," said the 48-year-old trucker, who has been driving corn and soybeans across the country in big rigs for most of his adult life.

'More deforestation'

The Kayapo have their own reasons for disliking the railroad plan.

They have experienced first-hand how building infrastructure across the rainforest accelerates its destruction, giving illegal miners, farmers, ranchers and loggers access to once-isolated regions of the jungle.

Mekragnotire points to the highway he is blocking, built in the 1970s by Brazil's military government, as an example.

"Just look at how much deforestation has increased since the highway was built. Imagine how it will be if they build the Ferrograo," he told AFP.

"See that smoke over there?" he asked, by way of illustration, pointing to the thick columns of smoke rising from the forest, set by farmers and ranchers clearing new land.

The practice is common in Brazil, the world's biggest soybean producer and second-biggest beef producer. But it is devastating for a forest whose preservation is vital to curbing .

Combine harvesters crop soybean during in Mato Grosso state, Brazil

'Environmental gain'

Spanning nearly 1,000 kilometers (620 miles), the railroad is planned to run from the city of Sinop, in Mato Grosso state—the heart of farm country—to the port of Miritituba on the Tapajos river, an Amazon tributary.

From there, Brazil's key agricultural exports will make their way to the Atlantic and myriad destinations around the world, above all China.

The railroad will largely follow the path of the existing highway.

Planners say it will not go through indigenous lands. It will cross the Jamanxim National Park, but only along a strip already approved by Congress for passage of the BR-163.

The $1.5-billion project is backed by multi-national distributors such as Cargill and Bunge, which say shipping their product by road is too slow and expensive, hurting Brazil's competitiveness.

The government plans to hold a tender for the project in the first half of 2021, with a target launch date of 2030.

"It's a highly viable project that will reduce shipping costs by between 30 and 35 percent and halve transport time," said Edeon Vaz Ferreira, executive director of the Mato Grosso Pro Logistics Movement and a lobbyist for the project.

Far from harming the environment, he argues, the project would help protect it.

"The train will have 160 cars and transport 12,000 tonnes with three locomotives, instead of the 300 semi-trucks you need now," he told AFP. "The environmental gain will be huge."

Environmentalists are not convinced.

The project "will increase demand for land and lead to the deforestation of 2,043 square kilometers (789 square miles) of native vegetation in Mato Grosso," said the Climate Policy Initiative.