The Isiboro Sécure Indigenous Reserve and National Park might strike many as paradise on earth. Located in the verdant headwaters of the Amazon basin, the protected area is home to a stunning array of species, from howler monkeys and spectacled bears to myriad birds and insects, not to mention 64 native communities and billions of tons of forest carbon.

It is the last place where the credentials of Evo Morales as a globally renowned defender of indigenous rights and the Pachamama, or Earth Mother, seem likely to be called into question. But Bolivia's President now finds himself engulfed in a bitter dispute over his plans to put a £260m road through the middle of this stunning wilderness.

On Monday, about 300 members of the Chimane, Mojeño and Yuracaré indigenous communities that inhabit the 3.4 million-acre park – universally known by its Spanish acronym Tipnis – began a march against the proposed highway, from the steamy provincial town of Trinidad up some 10,000ft to the Andean capital La Paz. The group is expected to take about 30 days to complete the 400-mile trek, during which time organisers expect sympathisers to massively swell their numbers.

"President, tell me at what point we betrayed our nation," said Adolfo Chávez, leader of the Indigenous Peoples' Confederation of Bolivia, at the start of the march. "We want to live in peace, with development that respects our lands. Your shovels will crash into our children. That is why you do not want a binding consultation. So our spears and arrows will be ready for the mechanical diggers which want to destroy our virgin territory."

For his part, Mr Morales, who last year took Bolivia on a lonely stand against the Cancun climate accord which he said would endorse "ecocide and genocide", appears equally determined to push ahead with the road, saying it will be built "no matter what". He believes it will integrate remote rural communities into Bolivia's economic development. Earlier this week, the President accused the protesters of intransigence. "The dialogue [process] is always open. I am very sorry that they do not want to participate in the dialogue," he said. "I can understand that this is a political act."

Mr Morales may be right on that point. The march is one of three major protests against his government that were deliberately timed to coincide this week. In El Alto, the vast shantytown above La Paz, residents blockaded thoroughfares to demand a national census that could lead to more government resources allocated to their rapidly expanding community, while in the southern city of Potosí demonstrators took to the streets to complain about the government's supposed failure to deliver development projects.

But it is the Tipnis protest that is the most resonant, not least because of the heavy green symbolism that Mr Morales has frequently employed during his presidency. Local people, who have boycotted the statutory planning process for the road, claim it would literally pave the way for the destruction of their forest, allowing loggers, poachers and land-squatters fleeing poverty in the Andes to enter the park. It has also not escaped their attention that there are oil reserves under the Tipnis.

Maria Teresa Vargas Rojas, head of the environmental group Fundacion Natura Bolivia, said Mr Morales' discourse on the environment was "not always consistent". "The President should listen to the indigenous communities in the Tipnis. He might learn something," she added. "They are not saying they are against development. But they want it on their own terms and in a way that benefits them."

The question now for Mr Morales, an indigenous Aymara former coca grower and union leader, is whether the unrest comes from just a few pockets of disaffection or represents the mood of the poor majority who re-elected him in 2009 with a landslide.

"Without a doubt, they are three distinct problems," said Franklin Pareja, a political science professor at La Paz's State University, of the Tipnis, Potosí and El Alto protests. "But they are not isolated because the fundamental reason that they have arisen is that the government's management of conflicts is deficient at tackling them early on."

On his election in 2006, Mr Morales was widely hailed as the first of Bolivia's 80 presidents to be indigenous. But any lingering honeymoon Mr Morales might have had with the electorate came to an abrupt end last December when the government attempted to remove petrol subsidies. National protests, some violent, forced the President to back down.

Despite Mr Morales' posturing on the environment, Bolivia's economy remains heavily dependent on the mining and oil industries. The country's main exports include crude oil, natural gas, zinc ore and tin.

Although Mr Morales has nationalised oil and gas reserves and imposed new contracts with higher royalties on foreign mining firms, Bolivia remains one of the poorest nations in the Western hemisphere and the President has been unable to break Bolivia's economic dependence on the export of raw commodities, which have historically taken a high environmental and human toll.

A biodiversity hotspot

* The arc that sweeps through Colombia, Ecuador, Peru and Bolivia where the Amazon meets the Andes is widely recognised by scientists as the most biodiverse zone on the planet. Untold species have evolved in narrow altitudinal bands where the rainforest climbs the Andean foothills.

* Sometimes known as the Tropical Andes, the region contains roughly one sixth of all plant life in just 1 per cent of the world's terrestrial surface. It is also home to some of the last indigenous people still living in isolation from the outside world.