Atmospheric nitrogen implicated in North Atlantic algae blooms

North Carolina’s more than 3,800 open-pit pig waste lagoons are of particular concern.

Academics met in Chapel Hill, NC in June to discuss the problem of atmospheric nitrogen deposition – when emissions come back to land and water after travelling some distance – and the North Carolina Environmental Defense Fund (NCEDF) has mounted a Hog Watch campaign to educate the public.

The Union of Concerned Scientists’ study rates pollution from pig, beef and poultry farms as just as important as emissions from sports utility vehicles. North Carolina’s moratorium on new pig factory farms is due to end on 1 September.

The NCEDF is pressing the state legislature to implement a less primitive system of pig waste treatment. NC produces 19 million tons of pig waste annually. Monitoring of atmospheric nitrogen deposition is not adequate, according to the NCEDF.

In addition to polluting NC’s rivers and coastal regions, a recent study has associated algae bloom activity in the North Atlantic Ocean Basin with atmospheric nitrogen levels. The study, written by Hans Paerl and published in the June issue of Ambio magazine, was funded by a North Carolina Sea Grant.

“The study is significant because it reconfirms that atmospheric nitrogen has been found to be a regional and global source of pollution,” said Paerl, who is professor of marine and environmental sciences at the University of North Carolina at Chapel Hill Institute of Marine Sciences. Paerl’s team found that atmospheric nitrogen accounted for 46-57% of the new nitrogen deposited in the North Atlantic Ocean Basin.