Mitigating ammonia emissions from typical broiler and layer manure management - A system analysis

Abstract

Broiler and layer productions are important ammonia (NH₃) emission sources in the livestock industry. Here, we present the first meta-analysis and integrated assessment of NH₃ emissions and mitigation potentials for typical broiler litter manure management system (MMS) and layer manure belt MMS based on data from 96 studies. A total of 10 integrated NH₃ emission factors (EFs) and the NH₃ mitigation efficiencies (MEs) of 14 available options were provided. The estimated NH₃ emissions from the baseline scenarios of the broiler litter MMS and the layer manure belt MMS were 84.1 ± 5.9 kg AU^-1 yr^-1 and 53.5 ± 15.8 kg AU^-1 yr^-1, respectively. The NH₃ mitigation for the broiler litter MMS should be focused on the in-house stage, while the mitigation in the layer manure belt MMS should be focused on the outdoor and land application stages. The recommended NH₃ mitigation options for the in-house stage, the outdoor stage and the land application stage were acid scrubber (-92.5%), compost biofilter (-71.9%) and changing the manure surface application to incorporation (-83.0%), respectively. The recommended mitigation combinations of low crude protein (LCP) diet, acid scrubber, compost biofilter and manure incorporation achieved the highest NH₃ mitigation efficiency from both broiler litter MMS and layer manure belt MMS, by 89.3% and 84.8%, respectively. The results of this study have important implications for developing sustainable poultry production systems from the viewpoint of NH₃ mitigation. The environment issues such as the other reactive nitrogen emissions and the greenhouse gas (GHG) emissions should also be considered in the future.

Keywords: Ammonia; Broiler; Layer; Manure management chain; Mitigation.