Chemical acidification outperforms slurry additives relative to abating ammonia and methane emissions during storage of cattle slurry

Storage of cattle slurry is a major source of ammonia (NH 3 ) and greenhouse gas (GHG) emissions. Chemical acidification and slurry additives can reduce these emissions, particularly NH 3 and methane (CH 4 ) emissions. However, the efficacy of commercially available biological slurry additives in lowering emissions is unknown. This study investigated the effectiveness of six commercially available slurry additives and sulphuric acid in reducing NH 3 and CH 4 emissions for improved cattle manure management. Sulphuric acid was the only effective treatment at reducing emissions from stored cattle slurry, with 41% and 74% reductions in NH 3 and CH 4 , respectively, relative to the untreated slurry. However, commercial slurry additives failed to significantly reduce either of these emissions. This study confirms that chemical acidification is currently the best method for reducing NH 3 and CH 4 emissions from stored cattle slurry.