How do NH3 emissions relate to nitrogen use efficiency of livestock production?

Groenestein, C.M.1, Hutchings, N.J.2 , Haenel, H.D.3, Amon, B.4, Menzi, H.5, Mikkelsen, M.H.6, Misselbrook, T.H.7, van Bruggen, C.8, Kupper, T.9, Webb, J.10

1 Wageningen UR Livestock Research, De Elst 1, 6708 WD Wageningen,,

2 Dept. of Agroecology, Aarhus University, Research Centre Foulum, 8830 Tjele, Denmark

3 Thünen Institute of Climate-Smart Agriculture (TI-AK), Bundesallee 50,38116 Braunschweig, Germany

4 Leibniz Institute for Agricultural Engineering, Max-Eyth-Allee 100, 14469 Potsdam, Germany

5 Agroscope, Inst. For Livestock Sciences, P.O. Box 64, CH-1725 Posieux, Switzerland

6 Dept. of Environmental Science, Frederiksborgvej 399, 4000 Roskilde, Denmark

7 Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Devon, UK, EX20 2SB

8 Organisation, address, city, state, postcode, website, Email

9 Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences Laenggasse 85 CH-3052 Zollikofen

10 Ricardo Ltd, Gemini Building, Harwell, UK. OX11


Ammonia (NH3) emissions from livestock production systems can be substantial but difficult to measure. Here we explore the relationship between NH3 emissions, the emission intensity (NH3-N emitted/product N) and the more easily measured feed Nitrogen Use Efficiency (NUE). Using a conceptual model, we find that the relationship between emission intensity and NUE is equivalent to that between NH3-N emission and feed N intake. Furthermore, there is a linear relationship between the two, with a slope that is dependent on characteristics of the animal and its feed, and the manure management system. This is illustrated using data taken from the emission inventories of six European countries, which found a linear relationship, with much variation within a commodity type. Using the same data, we show how the effects of animal and feed characteristics can be separated from those of the manure management system.