Emissions of NH3, N2O and CH4 from dairy cows housed in a farmyard manure tying stall (housing, manure storage, manure spreading)

Emission measurements from dairy cows housed in a tying stall were carried out with the aim of finding factors that influence the amount of emissions and means to reduce emissions. All sectors of animal husbandry were investigated. This enabled calculations of emissions for the whole management system including housing, storage and spreading of manure. Emissions during aerobic composting and anaerobic stacking of farmyard manure were compared. NH3 and N2O emissions from tying stalls for dairy cows are low (5.8 g NH3 LU−1 d−1, 619.2 mg N2O LU−1 d−1). Methane emissions from the animal housing are mainly caused by enteric fermentation. During storage and after spreading of farmyard manure substantial differences concerning NH3, N2O and CH4 emissions were observed with composted and anaerobically stacked farmyard manure. The compost emitted more NH3 than the anaerobically stacked farmyard manure. About one third of the NH3 emissions from the anaerobically stacked farmyard manure occurred after spreading. Total N losses were at a low level with both storage systems. Greenhouse gas emissions (N2O and CH4) were much higher from the anaerobically stacked farmyard manure than from the composted one. As these are ecologically harmful gases, they have to be considered when judging the form of manure treatment.