There are days when renowned Russian ecological crusader Marina Rikhvanova feels like an endangered species.

She has gotten used to a certain amount of ambient harassment -- the intelligence agents rifling through her files, the bank accounts abruptly blocked, the phone she believes is bugged. It comes with the territory.

As Russian President- turned-Prime Minister Vladimir Putin has rolled back democracy and downsized civil rights, activists of all stripes have struggled to operate. But with the Kremlin and big business so intertwined that they've become virtually indistinguishable, the Russian elite appears to reserve a special brand of venom for those who tend to clash most directly with business: environmental advocates.

"We are preventing them from doing very quietly what they want to do very quietly," says Rikhvanova, 47, seated in the office of her Baikal Ecological Wave organization in this Siberian city.

Russia's efforts to reclaim lost superpower status are staked on the exploitation of vast natural resources, from oil and natural gas to timber and diamonds. Against this backdrop of runaway capitalism, independent ecologists such as Rikhvanova are voices in the wilderness.

Short, stolid, frowning skeptically through tinted eyeglasses, Rikhvanova seems an unlikely foil to Putin. She came to her love of nature early in life, and still recalls the smell of spring in the Siberian village where her parents taught school. Her father took her to explore forests and to gaze over the vast stretches of Lake Baikal.

The world's deepest and oldest freshwater reserve is treasured by evolutionary biologists as a liquid cornucopia of rare species. The lake holds an estimated 20% of the world's fresh water and is a UNESCO World Heritage Site, but has repeatedly been put at risk by the march of Russian industry.

"It's huge, tremendous, mysterious, beautiful," Rikhvanova says, watching tiny winter birds peck at the feeder dangling outside her window.

"It's 25 million years old, and every organism, every being, in Lake Baikal is a witness to this history."

Rikhvanova's first major clash with Putin erupted in 2005 when a pipeline to transport oil from the Siberian fields to the Pacific coast was slated to skim within half a mile of Lake Baikal. Scientists, including Rikhvanova, warned that the area is prone to earthquakes, and that an oil spill could prove catastrophic for the lake.

Transneft, the state pipeline company, did not respond to the warnings, and the government's own environmental experts backed the pipeline company. Only after Rikhvanova's organization and other environmental groups drummed up street protests in Siberia and Moscow did the government blink: Putin produced a red pen during a televised meeting, gestured at a map and ordered the pipeline rerouted.

But for Rikhvanova, it was a wan victory.

"It demonstrated the uselessness of the legislation and legal system in Russia, the management of ecological issues, that the whole thing was corrupt," she says. "It should have been based on assessments and expert opinions. Instead, the president took a crayon and drew a line on a map."

Her next battle was already on the horizon. In January 2006, Putin announced Russian plans to create an international uranium enrichment center, a factory that would provide enriched uranium to any country within international law. Putin described the center as a nondiscriminatory way to spread nuclear energy without divulging nuclear secrets.

Soon, state nuclear giant Rosatom had unveiled plans to open the center on the grounds of a former chemical plant in Angarsk, just a few hours from Lake Baikal. The project has steamed ahead, despite vehement protests from Rikhvanova and other local ecologists.

Rosatom spokesman Fyodor Dragunov insists that the plant management has dealt openly with the community, inviting women's groups and youth organizations to take guided tours of the plant; meeting with the public; and releasing safety information.

"Experts and specialists have concluded that the plant does not pose any danger," he says.

"You need to exclude these fanatics who are not satisfied with conclusions and results. It's practically useless to explain anything to them."

Rikhvanova and other environmentalists accuse Rosatom of hiding behind a screen of carefully packaged excursions and scientists who are paid to downplay the plant's risks.