The list of environmental effects from agricultural chemical use is long and unsettling. Now, there’s another worry to add to this list – the impact they’re having on U.S. national parks.

According to a recent study published in the journal Atmospheric Chemistry and Physics, our national parks (38 out of 45 to be exact) are increasingly threatened by the “accidental fertilization” of ammonia that is brought into these pristine natural landscapes from car exhaust, power plants, and increasingly, industrial farming.

“The vast majority, 85 percent, of nitrogen deposition originates with human activities,” said lead researcher Daniel Jacob of Vasco McCoy Family Professor of Atmospheric Chemistry and Environmental Engineering at the Harvard School of Engineering and Applied Sciences (SEAS) via e! Science News. “It is fully within our power as a nation to reduce our impact.”

Among the most threatened parks are those closest to heavy industrial activities such as Great Smoky Mountains National Park, Cuyahoga Valley National Park, and Sequoia National Park, reports the LA Times.

So what happens when there is too much nitrogen or ammonia in an environment like a national park? According to e! Science News, these chemicals can “disrupt the cycling of nutrients in soil, promote algal overgrowth and lower the pH of water in aquatic environments, and ultimately decrease the number of species that can survive.”

Nitrogen emissions should then be taken very seriously. And they are – to an extent.

Air pollution regulations for nitrogen oxides (NOx) have been set in place and NOx emissions are estimated to decline by up to 75 percent by 2050. But ammonia, the new worrisome chemical, remains unregulated and, according to the study, may increase in use by up to 50 percent as the U.S. population grows and more fertilizer and livestock are required to produce enough food.

“Ammonia’s pretty volatile,” said Jacob in a statement from SEAS. “When we apply fertilizer in the United States, only about 10 percent of the nitrogen makes it into the food. All the rest escapes, and most of it escapes through the atmosphere.”

Harwood forests and lichens are particularly sensitive to nitrogen emissions. Hardwood trees begin suffering once nitrogen deposition is between three to eight kilograms per hectare per year. The new study shows that the deposition rate is actually around 13.6 kg/ha/yr. And lichens too are feeling the heat at 6.7 kg/ha/yr, which falls within their critical load of 2.5 to 7.1 kg/ha/yr, the researchers reported in a SEAS statement.

“The lichens might not be noticed or particularly valued by someone walking around a national park, but they’re integral for everything else that’s dependent on them,” said co- author Raluca Ellis.

The study’s research team, which was comprised of scientists from Harvard SEAS, the National Park Service, the USDA Forest Service, the U.S. Environmental Protection Agency (EPA) and the University of California, Irvine, strongly believes something must be done on a national scale to halt the potentially detrimental effects of ammonia emissions.

“Air quality regulations in the United States have always focused on public health, because air pollution leads to premature deaths, and that’s something you can quantify very well. When you try to write regulations to protect ecosystems, however, the damage is much harder to quantify,” said Jacob. “At least in the national parks you can say, ‘There’s a legal obligation here.’”

“It’s a national issue, and I think that’s why having the national perspective was so important,” Jacob added. “We’ve shown that most of the nitrogen deposition to parks in the United States is coming from domestic sources. It’s not coming from China; it’s not coming from Canada — it’s something we can deal with, but we need to deal with it at the national level.”

Jacob is right. We must deal with it at the national level, and deal with it now without delay. For starters, fertilizers and pesticides should be rethought, as should industrial farming, which already has too many problems under its belt in addition to ammonia emissions. Our world is already on a downward spiral environmentally and we need to demand, and I mean seriously and persistently insist that our governments and our businesses do something about it.

Image source: Ken Thomas / Wikipedia Commons