Changes in swine ammonia emissions associated with improved production management

Area of Science:

• Environmental Science
• Agricultural Science
• Atmospheric Chemistry

Background:

• Swine manure management is a significant source of agricultural ammonia (NH3) emissions.
• Ammonia emissions contribute to increased ammonium deposition in sensitive ecosystems.

Purpose of the Study:

• To assess the impact of improved swine manure and animal management on lagoon nutrient loading.
• To quantify changes in ammonia (NH3) emissions from swine lagoons between 2001 and 2018.

Main Methods:

• Utilized archived lagoon chemistry data from 182 swine farms (106,000 analyses).
• Applied process and empirical (statistical) NH3 volatilization models.
• Analyzed lagoon chemical properties and climate data.

Main Results:

• Nutrient levels in swine lagoons decreased significantly (18-93%), with a notable exception of increased copper (41%) in finisher lagoons.
• Process models indicated NH3 emission reductions of 49% (finisher) and 25% (sow) due to lower nitrogen and pH.
• Empirical models predicted even greater NH3 emission decreases, up to 54%.

Conclusions:

• Improved swine farm management practices have effectively reduced lagoon nutrient loading.
• These management changes have led to substantial decreases in ammonia (NH3) emissions from swine lagoons.
• The findings highlight the success of targeted interventions in mitigating agricultural air pollution.