The high price of gold has drawn thousands of miners to a region of south-east Peru, but deforestation and the high levels of mercury used in mining has led to fears of an imminent ecological disaster, as Dan Collyns reports.
It is only from the air that you can see the full extent of the destruction.
The forests seems almost endless until it is abruptly interrupted by the raw colours of sand and earth; rivers torn open and thousands of hectares denuded and pocked with dead, stagnant pools of water.
Alluvial gold mining in Peru's southern Amazon rainforest has spread, driven by the high price of gold, now more than $1,100 (£680) per ounce, or $36 a gram.
Close to 200 sq kms (77 sq miles) of jungle have been lost in the evocatively named Madre de Dios (Mother of God) region.
"To know what we are losing, this area of Peru - the western Amazon - is the world's enclave of biological diversity," says biologist Ernesto Raez, who heads the Environmental Sustainability Centre in Lima's Cayetano Heredia University.
"Counted in terms of richness of species, this is the place where world records have been obtained for butterflies, birds, amphibians; you name it."
Over the years, more than 1,500 jungle mining concessions have been granted by the energy and mines ministry, although most did not get final approval.
But the informal sector has grown out of control, and now almost a quarter of the gold produced in the world's sixth largest producer is illegal.
The vast majority of it comes from Madre de Dios, where local non-government organisations believe there could be up to 30,000 miners.
Peru's environment minister, Antonio Brack, says enough is enough.
"If I, as the environment minister, allow the miners to do what they want, within 20 years Madre de Dios will be an ecological disaster the like of which mankind has never seen," he says.
Mr Brack is calling for 80% of Madre de Dios to be closed to miners, illegal or not, and a ban on river dredgers and other heavy machinery used in mining.
But he must tread carefully with the thousands of miners who will fight to protect their livelihoods.
"No one wants a bloodbath," he says. "Despite the fact that the miners are illegal we are engaged in dialogue with them but that doesn't mean that the state will allow itself to be pressured by mafias."
Delta Uno is one of the Wild West-style towns that have grown out of the Amazon gold rush. Swelled with poor migrants from Andean regions, it bustles with commerce and gold traders dot every corner paying $30 a gram.
But there is a dark side to the boom. While young men ride around on shiny motorbikes, many young women and under-age girls lurk in garish bars. Many of them are victims of people-trafficking mafias who use them to entice miners flush with cash.
"Like it or not the economy of our region is based on mining," says the mayor, Pedro Donayre, a former miner, who no longer wants his town to be on the margins of the law.
"I'm in favour of mining but it does need to be legitimised. The state needs to come here and educate the miners how to extract the gold safely without polluting and help us change rather than demonising what we do."
'Good for health'
For every gram of gold extracted, up to three times more mercury is needed. The toxic metal is used to bind with the gold particles, forming an amalgam which makes them easier to extract.
It is cheap and efficient; so cheap that much of the mercury is left in the rivers and lagoons, poisoning the flora and fauna and in turn passing into the food chain.
Peru's environment ministry estimates there could be up to 40 tonnes of mercury dumped each year.
Many of the miners appear to be cavalier in their use of mercury and its effect on their own health.
One of the older men, nicknamed Viejo Gallinazo, or Old Buzzard, swears by it.
"It's cured my heart problems," he says. "It doesn't pollute, on the contrary, it's actually good for the health."
He lives in a makeshift camp on the edge of a football pitch-sized crater full of dead tree trunks and muddy water.
Day and night, diesel-powered generators whir, powering hoses and suction pumps which suck up the earth, spewing mud down carpet-covered ramps that trap the gold particles.
The workers churn up tonnes of earth in 24-hour shifts, pausing at dawn to wash out the carpets and extract the gold using the mercury.
The heavy work produces around 20 to 25 grams of gold - a small profit for the workers - but it is part of a black market in illegal Peruvian gold worth around $500m, according to experts.
The environment ministry estimates around 50 tankers of petrol and diesel reach the mining zone every day, providing fuel for hundreds of bulldozers and heavy diggers.
Practically, halting the mining, at least in the short term, is impossible. Poverty and lack of opportunity in the highlands continue to force people like Paulino Chavez to seek work in the jungle.
"I earn a pittance but it's more than I can get in my village," says the father-of-seven, who earns around $8-a-day. "I know we're killing the jungle, this land will never be the same."
There are other factors at work. Climate change in the Andes is already affecting small farming communities, forcing them to adapt or move elsewhere.
The near completion of the Inter-Oceanic Highway, which cuts a swathe straight through this once inaccessible part of the Peruvian Amazon, will lead to migration on an unprecedented scale.
The road, which will link Pacific ports in southern Peru to the Atlantic coast in Brazil, could well become the greatest factor in the environmental degradation of this once pristine pocket of biodiversity.