The purpose of this CAST Issue Paper (IP 47) is to go beyond the generalizations and accusations often associated with the air quality topic. Experts from six universities examine a large amount of data and focus their information and conclusions around the key livestock areas: swine, poultry, dairy, and beef. Their critical analyses look at a wide scope of issues, from greenhouse gas emissions to the logistics of manure storage facilities. The U.S. Environmental Protection Agency is increasing efforts to monitor emissions from agriculture, so further research is important for all parties involved, and this paper provides solid, science-based information.

This issue paper outlines the technologies and approaches that poultry and livestock producers can use to decrease the amounts of nitrogen and phosphorus entering the environment. This study focuses on two nutrients and addresses two environmental concerns: volatilization and manure nutrient distribution. Decreasing the nitrogen and phosphorus excreted by poultry, swine, or cattle can minimize these concerns.