"My father says there used to be snow here all year around just above the village," said Mario as he pointed to the stone walls that mark the edge of his small village Chucura which lies below imposing dark brown peaks.

"When I was a child, most of the peaks were covered with snow. About nine years ago, the snow melted. It has never returned."

Mario, a gentle and shy 30 year old, was our guide for a three-day trek which wound its way through steep-sided valleys and over dizzy icy-cold passes to the foot of the brilliant white snow-capped Huayna Potosi.

Our escape from the political tension of La Paz was a walk through the hills of his childhood.

We camped our first night just outside his village. In the morning, as we ate breakfast in the gradually thawing sunlight, we watched families with their herds of llamas pick their way up the old pre-Inca road taking food to market. In small courtyards, women laid out potatoes to freeze-dry them while sun-burnt children rolled hoops along the bumpy frosty ground.

But despite the apparent tranquil village life, it wasn't just the snow that was receding. Mario told us that the village had 120 families when he was a child. Now there were only 70 families left. When I asked how many families he thought would be left in 20 years, he half-jokingly said "One."

Mario had left the village with both his sisters. Only his parents remained. "I liked living here, but there were no possibilities for work." They had all moved to El Alto, the adjoining city to La Paz, which has become one of the fastest growing cities in the world.

It was disturbing to see so visually both a way of life and an environment disappearing. In some ways, they were strongly connected. The lack of snow melt-water meant that Mario's village's small hydro-electric power station now only temporarily worked.

As I looked up to see a glinting plane in the crystal-blue altiplano sky, I thought that many of the reasons for the change in their lives were completely out of their control. The villagers had little hope of ever flying in a plane, yet the growth in plane traffic is one of the major contributing factors to global warming.

The people in Chucura would also be unlikely to play any roles in trade negotiations which rarely prioritise small-scale farming which has been carried out for centuries in this beautiful but inhospitable landscape.

Yet, ironically when I asked Mario what he thought about global warming, he said he thought it was a good development. "The fact that there is no snow on the main pass means that the Government is more likely to build the road to the village that they have promised."

Roads of course mean easier access to markets. But roads are also often part of a model of development in which rural life and the environment are the first to be sacrificed. It seemed a tragic hope in the face of a receding world.

Links:

• Friends of the Earth Climate Change campaign
• Calculate and offset carbon emissions
• Small scale farming - Food First and Via Campesina

"A wash, cut and blow dry. Well that would come to between 55 to 60 Bolivianos (about £4 or $7)," said the slightly camp but not especially friendly hairdresser.

Ok, so no surprises there. Except that the quote was for an imaginary poodle that I pretended to own when I curiously went into the dog's hairdressers for a quote.

The canine coiffeur can be obtained just five minutes from where I am currently staying with a friend of a friend in the south of La Paz.  The cost is almost five times what a third of the population of Bolivia earn in a day.

Just beyond the poodle parlour is a street that could easily be London full of coffee shops, shopping malls, fashion boutiques and more 4x4s than you can see even on a good day in Chelsea. Rich Bolivians interspersed with the occasional gringo stroll contentedly through the streets wearing the latest designer shades and American fashion.

The only thing that was a bit unusual were the amount of windows that were covered by newspaper - hurriedly pasted up as rumours spread that the marches for nationalisation of gas were on their way down to the rich districts of La Paz.

The demonstrations have yet to make their way down, so the windows remain untouched unlike some banks and buildings up near the centre of town which got smashed in protests on Tuesday night. But the newsprint can't paper over the huge gulf that exists between people in Bolivia.

The visual contrast between rich and poor has been starker than ever this week, as the traditional centre of wealth in La Paz has been taken over by those who have for a long time been excluded from Bolivia's resources.

Surrounded by banks, government buildings and tourist agencies, residents from poor neighbourhoods in the adjoining city of El Alto have joined coca-chewing miners, weather-beaten Aymara men in deep red ponchos, indigenous women with swirling skirts and bowler hats, and teachers from schools across the city to call for nationalisation of gas.

Many have made great sacrifices to take part in the protests. Iriano, a miner had travelled six hours to join protests on Tuesday: "It is not easy for us to come here, but we came because we need reclaim these resources. We have been robbed for centuries and our government is robbing us again.”

In El Alto, a general strike for almost 2 weeks has had a serious impact on many of the small businesses that operate there. Today all the minibus drivers and taxis sacrificed a day's wages as a general transport strike took place across La Paz. Of course, not everyone supports the protests and some are tired after 3 weeks of intense protests on the gas issue, but most people I have talked to on the streets have expressed support for nationalisation.

Behind this sacrifice and the protests lies a more profound challenge to the gulf that lies between rich and poor, the powerful and the powerless. It was summed up in a banner on one of the marches on Tuesday:

"The time of the Q'aras is past. It is the time for the T'aras."

Gilberto, a construction worker in El Alto, who sported the placard explained:

"The Q'aras is an aymara word for the elite who make up 25% of the population and have who ruled for themselves in the 179 years since Independence whilst the majority, the T'aras (said with a click against the palate) live in misery. The gas law is part of this. They are selling themselves to the multinationals. We need to reclaim our resources for all the people."

The marches and protests and the radicalisation of demands by popular movements for nationalisation represents a fight back by those excluded from wealth and power for so long.  The shift explodes around issues like the gas, but has been taking place with increasing impact on Bolivia's politics for the last few years.

It was reflected in the elections in 2002 when a party, the Movement towards Socialism (MAS) representing campesinos and indigenous peoples came second and almost won the Presidency. 

In 2003, the largely indigenous population of El Alto played the key role in bringing down the Government of Sanchez de Lozada in the first stage of the "gas war." Recognising this growing force, the new President Mesa promised the recuperation of gas resources and an assembly to design a new constitution.

Neither have yet been delivered, which could go some way to explaining the anger and uncompromising attitude on the streets in La Paz. Again and again on the streets, I heard less about gas and more about the Government continuing policies of decades, of "robbing the country," "enriching themselves" , "leaving people in misery."

Yet before they have even taken power, the other world is fighting back. In La Paz, demonstrators are dismissed as trying to cause sedition, and papers talk mainly of the destructive effects of the marches and strikes on the Bolivian economy. Politicians openly encourage President Mesa to take a "firm hand' against the protestors ie use violence which thankfully he has refused to do.

In the East of Bolivia, strong business interests are driving forward demands for regional autonomy in Santa Cruz and Tarija due to a fear of losing control of "their natural resources." Their Cruceno campaign has successfully mobilised a strong regionalist (and at times separatist) sentiment from all classes of society.

The backlash was visibly shown today when a right-wing Cruceno group viciously beat up a group of landless and campesino marches in Santa Cruz. Meanwhile in La Paz, one of the demonstrators demands is for a rejection of autonomy which would merely fuel regionalist sentiment further.

In Bolivia, two worlds are clashing together.

For me, it has been inspiring to see those who have been excluded from power taking to the streets and fighting for their rights. But I feel the backlash could be an increasingly brutal one. In the fight for Bolivia's future, I fear it may be torn apart.

There is an interesting article in the Los Angeles Times about the way in which the current crisis in Bolivia divides people along often ethnic lines - and how this manifests itself in racist comments against the largely indigenous people involved in the bloqueos (road protests).

The majority of Bolivia is indigenous, but 30% is mestizo (mixed race) and 15% is white.

In Santa Cruz, which is largely white and mixed race, I felt an undercurrent of racism against those involved in the bloqueos, although this was also mixed in with a resentment at all things linked to the capital La Paz and the central government.

"We produce all the wealth, and it all goes to La Paz" said one taxi-driver. Another middle-class Cruceno (citizen of Santa Cruz) who had travelled many times to Europe told me he had just visited La Paz for the first time. He went for a week but came back after two days. "I hated it. I felt it was not my country."