The 37-year-old is still smarting from remarks made by two journalists from the Netherlands, who were researching a programme on the world's eco-resorts. On the whole, their report was favourable but they criticised the resort boat-driver's habit of throwing cigarette butts into the river and the use of diesel-powered rather than electric craft. Pawlik throws up his hands in mock despair.

'Again, for us, necessity and availability are the practical watchwords. And, yes, our boats burn fuel but I limit their use on a schedule that restricts their carbon monoxide output to an absolute minimum.

'I've looked at alternative power generated by the wind and the sun but the former's not practical here and the latter is not only massively expensive but also unreliable. We do have some solar power, which keeps the lodge going when it's not full, but totally kitting out the place with solar panels is for the future, when manufacturers can guarantee reliability and a sensible price.'

Built from a jigsaw-like kit of parts made from steel, laminated board, canvas and plastic, 4 Rivers is a stunning line of villas behind Koh Andet island, away from the main flow of the Tatai and its commercial traffic.

Waste, both the human kind and that scraped off plates, is a constant problem, says Pawlik. In recent years, there have been a number of reports of so-called eco-resorts dumping their rubbish on the side of roads, sluicing human waste into the nearest watercourse and generally leaving their mucky eco-footprint all over the landscape. According to Pawlik, all the waste water from his resort runs into a biological feeder that cleans it before pumping it back into the Tatai. Food scraps are fed to fish kept in a net between two of the villas. Other non-biodegradable waste is collected daily and disposed of at the rubbish dump in Koh Kong town, about an hour away. Plastic and glass is collected and sold for recycling.

While planning the resort, Pawlik identified his market as the upwardly mobile young middle class and parents of children who have left home, freeing them up for a bit of adventure.

'People don't come here to check out our waste disposal,' says Pawlik, 'but we are constantly looking at scientific papers and testing new methods that come on to the market. 'Green' to us is also our opportunity to introduce and educate people in the ways of this wild, beautiful and largely unspoiled corner of Cambodia.

'The Cardamoms are policed and patrolled by experts in conservation whose job it is to protect this special environment, to preserve it for generations to come. What we see is a tangle of undergrowth, the vivid colours of a butterfly. What we hear is the dawn chorus of a hundred songbirds, the chattering of monkeys and maybe the bark of a deer. The experts, though, can ... show you the footprints of wild and endangered animals and point out trees that have stood here for many hundreds of years and will continue to do so as illegal loggers are driven out of the forest.'

Pawlik is proud of his resort's record as an employer that offers training to local villagers (14 of his total complement of 20 staff are from the area).

Fostering a partnership with the local community was also important to the Wildlife Alliance (wildlifealliance .org), which set up the Chi Phat project, on the Piphot River about an hour by road from Koh Kong. The project is controlled and administered by an elected committee of villagers overseen by mentors from the conservation organisation.

Offering basic home-stay holidays, its remote location, deep in the Cardamom wilderness, severely limits the practical application of 21st-century eco-friendly amenities. Domestic rubbish goes to local tips, bathroom facilities are mostly squat toilets over a hole in the ground, generators and two mini grids provide limited and independent power and there are only bucket-style showers, using well water.

Oran Shapira is the group's ecotourism project manager. 'Education and partnership are the pillars of our project,' says the Israeli. 'Visitors can get up close and personal with local people by living with them, and sometimes see, and always hear, the wildlife.'

In the two years since Chi Phat opened, 2,200 visitors have experienced its down-to-earth tourism. 'The project has by-laws, regulations and a code of conduct in place to protect the natural beauty of the area,' Shapira says. 'Trekking and cycling are restricted to approved trails, jungle overnights are limited to specific camp areas and, for a chance to sneak up on the wildlife, we have kayaks and traditional rowing boats that people can use to explore the mangrove's many channels into the forest.'

A little over 35 years ago, the Cardamoms were a Khmer Rouge stronghold. Slash-and-burn agriculture, logging and the decimation of many animal species were the price paid for that occupation and the region is only now showing signs of a return to its natural form. In recent months there have been sightings of wild pigs and deer as well as a 10-strong herd of elephants.

The area's other big draw is its bird life. Threatened and presumed-extinct species, such as the great hornbill and yellow-bellied warbler, are staging a comeback to the extent that Chi Phat's twitcher tours are high on many visitors' agenda.

Shapira is quick to point out that the wildlife in this area has never been seriously surveyed because most of it is in virgin territory.

'This has to be one of the least-known, most-unexplored places on Earth,' he says. 'It is important that at some point a survey of all the indigenous wildlife [is conducted] to ensure that the perhaps hundreds of thought-to-be-extinct, rare and endangered species are not only recorded but [protected].'

The project has not only provided an income for local people but also turned former poachers into gamekeepers and guides keen to show off their forest to visitors - and protect them from its dangers. Many species of venomous reptiles and insects live here and the rainforest is a natural habitat for leeches that will latch onto the nearest warm-blooded visitor.

'We've had few medical emergencies since we opened,' Shapira says, 'and all visitors are required to sign a disclaimer before engaging in outdoor activities. Nevertheless, project staff will assist travellers who need to get treatment in Phnom Penh by boat, car or other means.'

From the balcony of Rainbow Lodge (www. rainbowlodgecambodia.com), visitors can, indeed, see rainbows. But the wildlife in this rainforest hideaway is much more interesting. Take, for example, the giant tokay geckos that cling to the rafters, eyes swivelling as they home in on praying mantises.

'They don't often miss,' says Gerard Chartier, 42, one half of the British couple that owns and runs the lodge. 'Yesterday, one literally flew across the room and landed with a heavy thud behind the bar, with a mantis clamped in its jaws. It then sat on the floor crunching its way through its lunch.'

The other half of the management team is Janet Newman, a former barrister from Birmingham. Having defended some of Britain's toughest criminals, she is perfectly capable of arguing the case for preserving and protecting the Cardamoms' fragile ecology.

Newman is using her legal skills to fight the building of a hydroelectric dam upstream on the Tatai River, citing the danger to wildlife and the possibility the project will reduce sections of the river to a stagnant lake. A few months ago, however, she was stopped in her tracks when villagers protested against her hard-line stance, fearing she was endangering their opportunity to get mains electricity. It wasn't until she chaired a rowdy public meeting that she was able to persuade the audience that the scheme would be of little or no benefit to them because localised power lines were not part of the plan. The promise of cheap electricity for all was simply a publicity ruse.

Newman's commitment to her lodge's immediate environment is not just aimed at protecting her investment. She's a voluble advocate of eco-sustainability.

Before turning her back on the Bar, Newman took a sabbatical. In 2005, she volunteered to work in the Botum Sakor National Park, southwest of where Rainbow Lodge now stands. She took to the jungle like Tarzan's Jane and decided her future lay in its tangle of undergrowth. She scoured the rainforest for somewhere she could house guests without harming the forest and its fragile eco-system.

'It was a battle between common sense, safety and sensitivity,' she explains, adding that where Rainbow Lodge now stands had been the site of a settlement for generations, which meant no trees had to be felled when she built the seven bungalows (named after the colours of the rainbow) that spin off the central meeting house like giant eyebrows. The wooden stilt houses have palm-frond roofs and solar-powered lights while rainwater (this is, after all, a rainforest) mixed with ground water is pumped to the bungalows and human and kitchen waste are disposed of down natural drainage channels, feeding subsoil worms and bugs.

'It's a constant battle against nature. Termites love wood, water rots it and running repairs are a daily fact of life,' says Chartier, while watching a butterfly the size of a bird skitter past. 'But it's worth it to be living among such a rare collection of flower, bird, insect and animal species, some of which were thought to be extinct, others that aren't in any of my reference books.'

Filling his photo albums and notebooks are creatures great and small, from a 2.5 metre Malayan pit viper that took to guarding the entrance to one of the bungalows, to the flash of iridescence caught as a scarlet minivet, chestnut-headed bee eater or blue-winged pitta flew through the twisted vines.

'There's plenty of other wildlife about but it is sensible enough to steer clear of humans,' Chartier says. 'The Cardamoms may be protected by law and patrolled by a small force of rangers but poaching live animals for collectors and killing for the table is a way of life for the people here.

'We've heard creatures moving around at night and seen their paw prints on jungle trails the next day. There have also been verified sightings of everything from Siamese crocodiles and hairy-nosed otters to Indochinese tigers, Asian elephants and fishing cats, but not by us. We live in hope.'

The pair's eco-commitment is laudable, but expensive.

'We recently upgraded our solar-power system to the tune of US$30,000,' says Newman. 'I am always on the lookout for green solutions to everyday problems. I would love to use only biodegradable products for washing powder, shampoo and soap, but they are almost impossible to find here. We religiously recycle most other things, such as cardboard and plastic bags.'

Newman and Chartier are fulfilling what they believe is a much more important ecological role by educating their staff of seven and their children. It not only makes commercial sense to teach the staff English, it also broadens their horizons.

'We are like a family,' says Newman. 'We are guests in their country and they have made us welcome, which we pass on to our guests.'

If there is one thing the owners of these three wilderness resorts have learned, it is that the prefix 'eco' is far less important in protecting a valuable natural habitat such as the Cardamoms than are training and sustainable employment.