Areng Valley is located in an area of the Cardamom Mountains of southwestern Cambodia, in Koh Kong province.
It is surrounded by 400,000 hectares of mountains covered with forest that houses an impressive array of flora with more than 30 species classified as rare, endangered or critically endangered. The area has been home to Siamese crocodiles, dragon fish, Asian elephants and the Chong people over several centuries.
When Alejandro Gonzalez-Davidson, 34, worked as a translator in Phnom Penh, he never imagined that what he witnessed in the valley would lead him to be deported from the country, along with the prospect of two years in prison for activities related to environmental activism.
His struggle to stop a dam construction meant his visa has been not renewed after 13 years of living in Cambodia. His case goes to trial on Friday and he is not allowed to return to the country -- not even to defend himself in court.
up the river: San Mala and Mr Gonzalez-Davidson travel along the Areng river in January last year, shortly before the Spanish activist was deported. Photo: Rod Harbinson
"I was very shocked by the destruction of the jungle and the effects it had on the indigenous people of that area," Mr Gonzalez-Davidson said.
In 2012, rumours of the construction of a large dam by Sinohydro, the largest Chinese state-owned hydroelectric company, began circulating. Most villagers stopped building in the area as they thought their homes would soon be demolished.
More than 13,000 hectares of jungle would be destroyed and 2,000 people displaced if construction went ahead.
Authorities told locals they would have to evacuate their homes so work could begin. Mr Gonzalez-Davidson stepped in and informed locals of their right to oppose the construction.
Environmental, social and economic concerns have stopped two other Chinese companies from building dams in the past.
Mr Gonzalez-Davidson started an organisation, Mother Nature, to campaign against the dam.
"I started doing it alone," he said. "And then I formed a relationship with one of the monks of the only temple in the area.
path of most resistance: Mr Gonzalez-Davidson and Ven Smey walk through a rice field in Areng. Photo: Luke Duggleby
"We started talking with the locals while they were fishing, sometimes in the jungle, sometimes in a rice paddy."
Mr Gonzalez-Davidson also started uploading videos, in Khmer, to YouTube denouncing the dam and highlighting the negative impacts on the forest and indigenous communities. The videos reached thousands of people and made him a mass phenomenon among young Cambodians.
Cambodia has one of the highest rates of deforestation in the world and, according to the UN Food and Agriculture Organisation, the country's primary rainforest cover has declined massively from more than 70% in 1970 to just 3.1% in 2007.
Last year, human rights organisation Global Witness said illegal logging operations were being carried out with the agreement of the government and military officials. Virtually all timber from the illegal logging has been transported to China, the organisation said.
Hundreds of economic concessions have been offered by the Cambodian government recently following a voracious demand for luxury furniture -- and the need for wood -- from China.
Naly Pilorge from Licadho, a Cambodian human rights NGO, said the government had used a variety of tactics to expropriate land through Cambodia, either in the creation of economic concessions for land or the construction of hydroelectric dams, including misinformation, intimidation and violence. In Cambodia, indigenous communities are rarely consulted and compensated, and forced evictions are common.
Villagers were afraid, Mr Gonzalez-Davidson said. Adding to this culture of fear was the death of environmental activist Chut Wutty, who was shot dead by police in 2012, after journalists had exposed illegal logging in the south of the country. A few weeks after the activist's death, a 14-year-old girl was killed in the midst of a land dispute between the community and a rubber plantation company. A few months later a journalist investigating wood cartels was found brutally murdered in the trunk of his car.
Global Witness says none of these cases have been investigated by the authorities. The last land and forests are disappearing in the country, so the battle for control is intensifying, explains Josie Cohen from the NGO. "Between 2002 and 2014, 14 environmental activists were killed in the country," she said.
Mr Gonzalez-Davidson gained the confidence of local residents. "They thought they were ants and the Chinese were elephants, though none wanted to leave," he said.
"We took several leaders to other areas where hydroelectric dams had been built so they could seen the consequences. They soon realised that the official government line was a lie."
When the first Chinese engineers arrived in the valley to begin construction, they faced strong local resistance. Monks had wrapped saffron robes around the trees. About 200 local people blocked the road and Mr Gonzalez-Davidson led protests and roadblocks to prevent the machinery from entering the valley. "We managed to stop the dam, but not without suffering," he said.
Eventually the dam project was relegated to the background by Prime Minister Hun Sen. Despite this, Mr Gonzalez-Davidson's visa was not renewed after it expired in February 2015, when he was deported from the country.
"If I were not a foreigner, I would not have been able to get away with what I did," Mr Gonzalez-Davidson said. "As I am Spanish, if they shoot or stop me it involves a response from other countries and that was what saved me."
Requests from human rights organisations, demonstrations and initiatives demanding that the activist be allowed to remain in the country were useless. Now he lives in a neighbouring country from where he continues raising funds adding his voice to environmental campaigns.
In August 2015, the authorities also arrested three Cambodian members -- Try Sovikea, San Mala and Sin Samnang -- of Mr Gonzalez-Davidson's NGO for taking part in a campaign against a sand dredging operation carried out in the southern province of Koh Kong.
This campaign continues today, Mr Gonzalez-Davidson said.
More than 1,000 local families living alongside the coasts of Koh Kong national park were forced to leave and have been dumped on infertile land without access to water, electricity or healthcare facilities to make way for a "development" project, he said.
Spreading the word: Alejandro Gonzalez-Davidson talks to an Areng community.
Up the river: San Mala and Mr Gonzalez-Davidson travel along the Areng river in January last year, shortly before the Spanish activist was deported.