VANCOUVER - Leaving British Columbia's old-growth forests standing may make more economic sense than cutting them down for timber, especially as the province looks to strategies to cut global warming, a new B.C. study suggests.

The report from Simon Fraser University challenges the status quo and uses Ministry of Forest data to show conservation wins out over logging when forests are valued for their role in capturing carbon from the atmosphere, protecting endangered species and providing opportunities for recreation.

The study backed by three environmental groups - Wilderness Committee, David Suzuki Foundation, and Ecojustice - used computer modeling to look at a variety of conservation and logging scenarios in a large tract of forest near Vancouver.

In almost every scenario, researchers say they found the value of the carbon captured and stored by the trees far outweighed the value of the lumber harvested from the logs.

Faisal Moola, science director for the David Suzuki Foundation, called the results a clear indicator that B.C. should be protecting its old-growth forest as it works with other western provinces to reduce global warming.

"The old-growth forests that we have are not only going to be a benefit in the fight against climate change, but there's also a significant economic windfall that could be celebrated by British Columbians," he said.

As the B.C. government begins to participate in a market for carbon credits with other western provinces and states, the study suggest the towering trees and the rich soil that surrounds them could become a cash crop for their carbon-storing properties.

Trees absorb and store carbon dioxide, using it as a building block in their development. When old-growth forests are harvested, that carbon is released into the atmosphere.

While much of global warming is caused by the combustion of fossil fuels such as gasoline, Moola said 25 per cent of the carbon dioxide that hits the atmosphere is caused by destruction of carbon stores of old-growth forests.

"The study shows there's direct economic benefit for B.C. if we can account for the carbon stored. B.C. should be protecting its old-growth forest as a strategy to combat global warming," he said.

The cap-and-trade system currently in the works through the Western Climate Initiative puts a ceiling on carbon emissions. Polluters that can't reduce their emissions will be able to purchase offsets to make up the differences mandated under the cap, which could give B.C. a significant revenue stream as the price of carbon rises, Moola said.

Duncan Knowler, the SFU associate professor behind the study, said the report is being conservative in its assessment of carbon prices, which are set to rise in coming years.

It values carbon at $20 to $150 per tonne, well below other estimates of $350 per tonne.

For example, at $75 per tonne, the forest in the Fraser timber supply area that is home to the endangered spotted owl is worth $1.64 billion, according to the study.

The study also excludes the role forests play in purifying water and protecting fish habitat, which could make for a more robust argument in favour of conservation, Knowler said.

And though the study considers only a specific area of Lower Mainland forest, he said the "surprising" results could prompt a rethinking of the current strategy around cutting old-growth forest.

While the end results may differ in other parts of B.C., "the basic principles . . . are not so different," he said.

"The biggest single benefit of preserving the forest was the carbon capture benefit, and you're going to get that in all old-growth forests."

The area studied is also home to B.C.'s entire spotted owl population - just 10 birds that Gwen Barlee of the Wilderness Committee says are on the brink of extinction in the province.

Barlee said the report refutes the government's main argument against protecting the owl: That it's too costly to protect their habitat, given the money raked in from logging.

Instead, the report shows that protecting the habitat of endangered species actually has direct benefit for community and human well-being, as well, she said.

"Preserving these old-growth forests . . . could potentially prevent species from going extinct, but could also help residents of B.C."

Barlee is careful to point out the report doesn't argue for an end to logging, but instead calls for a reduction in the coming decades.

"We need to value nature in a different way than we have in the past," she said.

The rapid decline in the spotted owl is one of many warning signs nature is giving, Barlee said.

"Typically, endangered species come from endangered ecosystems. You have an ecosystem in such trouble that it can't support a species that has lived there for millennia."