Executive Summary

Gaseous ammonia (NH3) plays a key role in the chemistry of the atmosphere. Natural emissions of ammonia from intensively managed animal and poultry operations sources may be equal in magnitude to those from known antropogenic sources. Emissions of this magnitude will make development of effective air and water strategies for reducing ammonia/ammonium concentrations problematic.

The objective of this proposal is to enhance our understanding of NH3 emissions from animal ans poultry operations in North Carolina. Specific objectives include: (a) to measure fluxes of NH3 using the dynamic chamber technique interfaced with an air conditioned mobile laboratory, from intensively managed animal (swine) and poultry operations, (b) to formulate gas exchange in terms of external properties (soil and lagoon factors, and atmospheric processes during temporal pattern in animal production that exist for each type of operation, predominant seasons of the year), (c) to develop a Geographical Information System (GIS) based inventory of emissions, and (d) using models, determine the relative importance of atmospheric depostion of ammonia to the Pamlico-Albemarle Sound, Neuse River, and Cape Fear Watershed and develop deposition map based on model projections.

Flux measurements addressed diurnal and seasonal variability of emissions, as well as variability within and between animal production operations. The results provided source strengths for NH3 from a variety of production operations. Incorporation of the flux measurements into a GIS database was used to develop a regional budget for ammonia from the sources and show net emissions and deposition of NH3 in eastern North Carolina (i.e. Coastal Plain Region). Such a projection would be key to formulating a critical load concept for management strategies in the river basins and the sensitive marine ecosystems.