Ammonia and Greenhouse Gases Emission from On-Farm Stored Pig Slurry

Abstract

Pig farms have achieved importance in the last few decades from the perspective of environment protection as a consequence of the intensive rearing systems in livestock production. Ammonia (NH3) and greenhouse gases (GHG), such as methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O), are emitted from slurry storage at farm prior to land application, but little is known about these losses under on-farm conditions in Spain. This study assessed the influence of management and environmental parameters on NH3 and GHG emissions from slurry storage in spring and autumn. Gas emissions were measured in a commercial pig-fattening farm from two lagoons (1000 and 768 m3 capacity, respectively) during 30 days by the floating dynamic chamber system in spring and autumn 2011 (average temperature 19 and 9 °C, respectively). Low NH3 and CH4 emissions were registered in spring (range 10–406 and 3–17 mg m−2 min−1, respectively) probably as a result of low pH values of stored slurry (6.5 to 7.0) and rainfall. High variability on NH3, CH4, and CO2 emissions was observed as a result of differences in temperature and rainfall. No NH3 emission and low CH4 and CO2 emissions were observed in autumn (average 1.2 ± 0.9 and 27 ± 22 mg m−2 min−1, respectively). Slurry loading operations increased NH3 losses from storage.