However, instead of the traditional coffin, deep in the earth, they want to be buried in just a shroud, at a more shallow level.

Their wish for a natural or green burial will be granted, with a section of the Gungahlin Cemetery being put aside for burials without coffins.

Cardboard coffins were already allowed in the ACT for burial and cremation, and people of the Muslim faith could be buried in the ACT in a shroud, without the need for a coffin.

The final go-ahead for natural burials was given last month.

The new site at Gungahlin Cemetery means people can be buried in a shroud or a biodegradable casket, among the Eucalyptus mannifera (brittle gum) and Eucalyptus melliodora (yellow box) in a natural one-hectare bush setting.

For those who wish to be cremated, their remains will be placed in a biodegradable container or placed directly into the earth.

Dr Furnass said he became interested in the environment after he retired from medicine.

He is concerned about the environment becoming more at risk partly from climate change, and about degradation of the soil.

"Humans are the only species that traditionally had to intervene [after death], normally all other species have been returned to the environment when they die, either to be eaten by predators or to rot," he said.

"Natural burials are a system whereby your body is buried at a shallower level than normal burials and therefore it composts rather than decomposes.

"It gives people an extra choice between bury, burn or compost.

"Composting is where you're burying the body where there is plenty of bacteria around, whereas with decomposing, it takes years to properly decompose, so composting is a natural harnessing of microorganisms to digest the body."

Dr Furnass said another reason he disliked traditional burials was the need for a headstone.

"That occupies lots of valuable space ... sooner or later the earth will be covered by concrete from buildings and graves," he said.

"With natural burials, your decomposing body helps to feed the trees, it's a nice natural circle.

"One of the disadvantages of combustion with cremation is very high temperatures are required, quite a lot of greenhouse gases are released.

"Natural burials avoid that and at the same time provide a pleasant sort of environment where your offspring can visit where you are buried and have a party or something.

"In other words, you have a positive impact on the environment rather than a negative one.

"From the environmental point of view and the aesthetic point of view, it's better I think."

Visiting the new section of Gungahlin Cemetery with her husband, Mrs Furnass said natural burial was "the only way to go".

"Because, apart from anything else, the trees will be absorbing the CO₂, so environmentally, it's very much better than the other way," she said.

The Bushland Cemetery at the Lismore Memorial Gardens was the first green burial site in NSW.

After it opened in July 2008, advocates for natural burial began asking the ACT government to take action.

Expectations of a change in policy were heightened when former Greens Assembly member Caroline Le Couteur was appointed to the board of the ACT Public Cemeteries Authority last year.

She is a natural-burial advocate who buried her parents in cardboard coffins.

Dr Furnass, a member of the Frank Fenner Foundation, previously wrote a paper in favour of natural burials, in which he said cremation was not a "clean" way of body disposal.

"Studies of emissions reveal that incineration turns people into at least 46 different pollutants," he wrote.