Standing by a tear-shaped pond nestled in the Tennessee woods, biology professor Jonathan Evans cupped a pregnant marbled salamander in his hands. The black-and-gray-spotted creature had trekked through the forest to lay her eggs by a pool of water that comes and goes with the seasons, he said, but the pond could disappear for good if loggers harvest the hardwood trees around it.

"This is a species that will go locally extinct due to forest conversion, without a doubt," Evans said. He added that salamanders "need both these forests and these pools. It doesn't look like much to a forester who's not trained ecologically. This is just in the way."

Evans, of the University of the South in Sewanee, is on the front lines of a war between timber interests and environmentalists over whether the state's booming timber industry is threatening one of the world's most diverse ecosystems, the Cumberland Plateau.

In a region where there is little regulatory oversight and nearly 80 percent of land is privately held, activists are concerned that conversion of the native hardwood forest to fast-growing pine is damaging crucial habitat for hundreds of plants and animals. Some foresters are clear-cutting swaths of oak, hickory and other trees and replacing them with pine plantations, a more lucrative but less ecologically valuable kind of forest.

But unlike the forestry feuds of the 1990s, when environmental advocates used litigation and regulation to protect the northern spotted owl and other species, this campaign is largely being waged with PowerPoint presentations in corporate boardrooms.

Allen Hershkowitz, senior scientist with the Natural Resources Defense Council and a leading crusader in what he calls a "local battle of global significance" -- spends most of his time pushing timber firms and their customers to protect the plateau and the surrounding Southern Appalachian Blue Ridge Mountains, a stretch of forest that extends from West Virginia and Kentucky through Tennessee to Alabama.

In what they call "market-based environmentalism," activists are pushing office supply stores, computer firms and even football teams to scrutinize how they buy paper products, much of which comes from the Southeast. And they are finding ready listeners in such corporate customers as the National Football League's Philadelphia Eagles and the Warner Music Group, both of which are taking a hard look at logging practices on the Cumberland Plateau.

Tim Sexton, a Los Angeles-based consultant who is working with Hershkowitz and "helps companies do well by doing good," said the Eagles and Warner Bros. are researching how their paper products are made.

"They are very interested in making sure the products in their supply chain come from environmentally friendly sources," Sexton said. "It's a way for our clients to be good citizens, to distinguish themselves as citizen brands."

Such environmental groups as the Asheville, N.C.-based Dogwood Alliance have scored some major victories: Within the past two years the Staples and Office Depot chains agreed to increase the average percentage of post-consumer recycled content in their paper products to 30 percent after being targeted by activists.

Dogwood Alliance spokesman Scot Quaranda said these tactics are essential in trying to save "one of the most special places on the planet that nobody cares about."

It may be too early to assess how much this strategy, modeled on campaigns such as the one that targeted Nike for its use of child labor overseas, is influencing forestry practices. But some firms are taking pains to demonstrate their environmental commitment. Greenville, S.C.-based Bowater Inc., the largest landowner on the Cumberland Plateau, has its logging independently monitored as part of a "Sustainable Forestry Initiative," although critics say these standards are too weak.

"We deal with science, we deal with facts, and it shows we have a sustainable resource in our operating areas, and we're doing our part to contribute to that," said Barry Graden, forestry development manager for Bowater's southeast woodlands operations. "There is a discrepancy between perceptions and reality."

But Evans, who has led a four-year study -- both federally and privately funded -- of logging on the southern Cumberland Plateau, said he and other scientists have identified "an alarming trend of forest loss that, if it continues, will lead to a fundamental change in the ecology of this region in Tennessee. . . . It's a showdown here of what's the future of the Southeast."

No one questions the unique nature of the plateau and the surrounding mountains, a region of 19.4 million acres that is home to more endangered and threatened species than anywhere in the country outside California's Central Valley. Its canopy of oak, hickory, black gum and red maple trees shelters streams and rivers with the highest concentration of aquatic diversity in the continental United States, featuring 230 fish species and 65 types of crayfish. It is also a kind of salamander kingdom, with more than 50 species.

Middle Tennessee State University biology professor Brian Miller said the plateau's broad mix of terrain -- with warm and cool streams, forest, valleys and subterranean areas -- allows a range of species to thrive. "The diversity of habitat on the plateau is tremendous," Miller said. "It is a unique physiogeographic region."

Graden, whose company supplies some of The Washington Post's newsprint and co-owns a Canadian newsprint plant with The Post, says his firm recognizes the value of preserving the ecological value of the land it farms.

Bowater has launched a year-long study to survey land it owns that constitutes "an area for ecological diversity of unquestioned geological significance," he said. In June, it donated 610 of the 380,000 acres it owns in Tennessee to the state and protected another 3,100 acres from development.

But environmentalists say the ongoing conversion of traditional hardwood forest to pine, which is three times more profitable, depletes calcium from the soil, which snails, birds and other creatures need for nutrients, and also alters the canopy structure upon which many animals and plants depend.

According to University of the South biology professor David G. Haskell, local bird diversity declines by at least a third in pine forests, and the switch also undermines migration habitat for neotropical birds.

"We're losing one of the jewels in the crown for southern bird diversity," he said.

Using remote sensing technology as well as on-the-ground research to survey 600,000 acres, Haskell, Evans and other Sewanee professors concluded that between 1982 and 2003, 20 percent of the native hardwood forest in the area was eliminated and converted to other uses. This rate of loss accelerated in the past six years, they said, and is expected to continue.

Timber officials, individual foresters and some state officials question these findings. They point to two broader studies, one of which suggested in 2002 that urbanization poses a greater threat to southern forests than harvesting timber, and an ongoing federal survey that concluded that the ratio of Tennessee's hardwood to pine forest has remained stable over the past 20 years.

"I'm not concerned about the overall forested areas on the Cumberland Plateau," said Steve Scott, Tennessee's state forester. He added that at least a third of Tennessee's loggers take a state-sponsored course to learn sound management practices.

Graden said after years of planting pine in Tennessee, Bowater converts only a few hundred acres a year -- less than 1 percent of its holdings -- from native forest to pine.

Part of the controversy stems from the fact that Tennessee does not require loggers to obtain a permit or notify the state before clear-cutting land, so there is no accurate accounting of how much forest is cut and converted. Private landowners say they should be free to decide what happens to their property.

Paul Tallent, who owns 300 acres on the foot of the Cumberland Plateau and sells to Bowater, recently cut down 40 acres of pine and hardwood forest, and replanted it with pine so his children would be able to harvest it in 30 to 40 years.

"Pine grows so much faster," he said, adding that he still has five acres of hardwood. "It's a balancing act. There's no lack of wildlife around here."

But state Rep. Mike McDonald (D), who has tried unsuccessfully to pass legislation regulating industrial clear-cutting, said he is worried removing hardwoods would hurt the habitat and the state's tourist industry.

"We're losing the very thing that attracts people to our state, and that's hardwood forest," McDonald said. "They don't come to Tennessee to look at pine plantations."