Greenhouse gas and ammonia emission abatement by slurry treatment

NH3, CH4 and N2O emissions from dairy cattle and pig slurries were quantified. The effect of the following treatments was investigated: untreated covered slurry, mechanically separated slurry, anaerobically digested slurry, slurry covered with a layer of straw, and slurry aeration. Measurements were carried out with dairy cattle and with pig slurry, in winter and in summer. After storage, slurries were band applied on grassland. NH3 emissions mainly occurred after field application. Promising mitigation options are low trajectory application techniques and proper timing of application. Anaerobic digestion is an effective means to reduce GHG emissions. Straw cover and slurry aeration showed negative environmental effects and are not recommended.