While rising carbon emissions are getting a lot of press, scientists studying Rocky Mountain National Park are as concerned about nitrogen.
Thursday, the Colorado Air Quality Control Commission will be briefed about the park’s nitrogen levels and on a proposal by the U.S. Environmental Protection Agency, the National Park Service and the state to reduce the pollutant.
“It could be devastating for the park if you can’t stop that,” said Brian Mitchell, environmental protection specialist with National Park Service. “We want to ward that off and get things back on track in the park.”
Next month, the commission meets in Estes Park to consider establishing a limit on nitrogen in the park – 1.5 kilograms per hectare per year, or a little more than a pound an acre.
Scientific research suggests the park’s nitrogen levels are about twice its “critical load” – the point at which an ecosystem begins changing.
“This is the first time – it’s a landmark – that any state has put in place a plan to protect the health of a national park in this way,” said Vickie Patton, senior attorney with the group Environmental Defense.
“At issue here is the crown jewel of Colorado. It is necessary to protect the park.”
Car exhaust, farm fertilizers and power-plant emissions are all sources of nitrogen compounds that reach the higher elevations of the park and act as a fertilizer that changes the park’s ecology.
Nitrogen levels in the park are nearly 20 times pre-industrial levels, officials say, and can be seen on a microbial level – elevated nitrates in surface waters and in spruce trees.
Nitrogen damage could lead to chronic acidification that kills fish and plants, such as native trout and alpine wildflowers.
Just outside of the park in the Niwot Ridge, alpine tundra-plant communities are beginning to favor sedges and grasses instead of wildflowers.
“The whole basic system is changing up there,” Mitchell said. “We need to stop the trend.”
The draft plan calls for reducing the deposition trend over 25 years.
Reductions at first would be attempted without further regulation – through federal and state emissions controls already underway and voluntary agricultural management practices.
“We have done an analysis that says we are likely to make progress by 2012 with just the things on the books,” said Mike Silverstein, a Colorado health department air manager.
Studies would help officials determine whether other regulations are needed.
“It’s a great first step,” said Jill Baron, the researcher with the U.S. Geological Survey who first identified the nitrogen problem in the park. “It’s correctable right now. We have this opportunity to turn it around.”
Staff writer Jeremy P. Meyer may be reached at 303-954-1367 or jpmeyer@denverpost.com.
