Changes in swine ammonia emissions associated with improved production management.

Swine manure management and storage have been implicated as major sources of increasing agricultural ammonia (NH ) emissions resulting in increased ammonium deposition in North Carolina. This study was conducted to establish how improvements in manure and animal management have affected lagoon nutrient loading and subsequent NH emissions determined from measured lagoon chemistry and climate data. Archived lagoon chemistry analyses from 182 farm lagoons (106,000 sample analyses) were used to evaluate trends in lagoon chemical properties.