There are certain things about North Carolina that people just know.
One: it provides the country with tobacco.
Two: it has a rich supply of soybeans.
And three: in North Carolina, pork barbecue is popular. Utz even provides a potato-chip tribute to the fine vinegar based taste in a Carolina-Blue bag.
But the long road it takes to reach national levels of crop production has led to many advancements in agricultural science, and in North Carolina, N.C. State has helped farmers since 1887 to help provide a surplus of produce.
Over the past few decades the agricultural industry has grown with the backbone of man-made fertilizers — soil infused with helpful nitrogen compounds that lead to more reliable plant growth. But scientists have recently discovered that the nitrogen compound ammonia injected in fertilizer boasts many negative side effects in addition to the initial benefits.
The agricultural issue surrounding ammonia is not reserved to fertilizers. Animal waste is a large contributor to ammonia emissions, supported by the Jan. 17, 2006, edition of EOS, a scholarly weekly newspaper of geophysics. EOS reported domesticated animals as accountable for 40 percent of worldwide emissions.
These new issues have sent a shock wave through the scientific community.
“Our culture has thought of agricultural as an industry that is relatively green in its production. And by green I mean pollution free,” Viney Aneja, Ph.D. and professor of Marine and Atmospheric Sciences, explained. Aneja has acted as the fountainhead in regards to agricultural air quality.
“Aneja is largely credited with bringing this issue to the national forefront,” Michael Tennesen reported in his 2006 article, “The Crisis in Agricultural Air.”
So ammonia does what exactly?
There are two types of agriculture: crop and animal, both of which emit ammonia. In crop agriculture plants are grown by adding fertilizer which contains ammonia, and in animal agriculture the excretion contains ammonia.
Aneja points out that there are two major issues surrounding this nitrogen compound.
“When ammonia enters the atmosphere … it is deposited all over the landscape, including our waterways and including the sounds on the coast,” he said. “The second is that as this pollutant is emitted it has a smell, which is the odor problem.”
Once increased amounts of nitrogen are distributed, the delicate balance of the biosphere is interrupted. For example, Tennesen points out the impact Hurricane Floyd had when it redistributed nitrogen from hog lagoons all over North Carolina — leading to abnormal algae growth which suffocates fish, eliminating prey for eagles and osprey.
The second issue, which Aneja identifies as “more profound and scientific in nature,” is the formation of particulate matter in the atmosphere.
“Particulate matter is a pollutant which has a host of other consequences, including negative effects on human health,” Aneja said. “Ammonia is what we call a precursor to fine particulate matter formation. It is a very important ingredient. Before these operations came around there wasn’t any ammonia so you didn’t see particulate matter, but now you do. So that is a major consequence to atmospheric pollutant — something that wasn’t there before is there now.”
But ammonia does have some benefits. Aneja said that nitrogen in its various forms is a nutrient. Essentially it acts as a fertilizer, and as ammonia is deposited over the land it can deposit nitrogen in areas starved of it, causing plants to grow.
“But by and large, the impacts are mostly negative,” Aneja said. “But we know very little actually, we are just beginning to realize the extent of the problem. We have some idea of what of the magnitude might be, but it varies quite a bit.”
Sounds like time for a conference
The workshop on Agricultural Air Quality: State of the Science currently in progress at the Bolger Conference Center in Potomac, Md. is the culmination of Aneja and Dean William Schlesinger of Duke’s Nicholas School’s efforts.
“It’s very important,” Chancellor James Oblinger said. “It’s the first ever conference, it’s worldwide and there are probably 350 to 375 people there with a whole range of expertise.”
State is co-hosting the workshop with the United States Department of Agriculture, according to Oblinger, and is an opportunity for scientists to come together on a relatively new issue in hopes of forming policy.
“It’s been an interesting interdisciplinary study across the spectrum, all focusing on waste reduction,” he said. “This is what takes place when you bring all the best minds to one place to focus on the challenge.”
The ability to create policy for ammonia emissions will result from the science decided upon by the experts at the workshop.
“[The USDA and National Science Foundation] are not only interested in the science, but they want to know what is the policy that is going to be formed with good science behind it,” Aneja said. “It might be that we don’t have the good science behind it, and if that is the conclusion then the nation has to decide if we put in the big bucks to complete the good science. And that would be a policy issue to be answered.”
Aneja likens the current scientific buzz around agricultural air quality to biotechnology or nanotechnology 10 years ago. People may have heard about it, but are far from understanding the science or implications surrounding it.
