Evaluation of mitigation strategies to reduce ammonia losses from slurry fertilisation on arable lands M. Carozzi a, ⁎, R.M. Ferrara b , G. Rana b , M. Acutis a a University of Milan, Department of Agricultural and Environmental Sciences, via Celoria 2, 20133 Milan, Italy b Consiglio per la Ricerca e sperimentazione in Agricoltura, Research Unit for Cropping Systems in Dry Environments, via C. Ulpiani, 5 – 70125 Bari, Italy HIGHLIGHTS ► Ammonia emissions from land-application of slurry were quantified. ► We examined and compared six different agronomic treatments in three locations. ► The faster was the soil-incorporation of slurry, the lower was the ammonia loss. ► The direct injection of slurry was found to be the best abatement strategy. ► The environmental factors were able to strongly influence the ammonia emission. abstract article info Article history: Received 9 July 2012 Received in revised form 24 December 2012 Accepted 26 December 2012 Available online 14 February 2013 Keywords: Inverse dispersion modelling Ammonia emission Slurry Incorporation Injection Surface spreading To evaluate the best practices in reducing ammonia (NH 3 ) losses from fertilised arable lands, six field trials were carried out in three different locations in northern Italy. NH 3 emissions from cattle slurry were estimat- ed considering the spreading techniques and the field incorporation procedures. The measurements were performed using long term exposure samplers associated to the determination of the atmospheric turbulence and the use of the backward Lagrangian stochastic (bLS) model WindTrax. The results obtained indicate that the NH 3 emission process was exhausted in the first 24–48 h after slurry spreading. The slurry incorporation technique was able to reduce the NH 3 losses with respect to the surface spreading, where a contextual incor- poration led to reductions up to 87%. However, the best abatement strategy for NH 3 losses from slurry appli- cations has proved to be the direct injection into the soil, with a reduction of about 95% with respect to the surface spreading. The results obtained highlight the strong dependence of the volatilisation phenomenon by soil and weather conditions. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Agriculture is known as the major source of atmospheric ammonia (NH 3 ), contributing to 50% of global NH 3 emissions (FAO/IFA, 2001) and over 90% in Europe (EEA, 2011). The reduction of atmospheric NH 3 emissions has become an important focus in many countries to prevent environmental issues connected to this compound (ECETOC, 1994; IPPC, 1996; Galloway et al., 2003) and to reduce the loss of nutri- ents and energy from agricultural systems (Harper et al., 1983). The main agricultural sources of atmospheric NH 3 are the storage and application of livestock manures, followed by the application of nitrogen (N) synthetic fertilisers (Asman, 1992). In fact, up to 10–30% of the total N employed as fertiliser and excreted by animals can be lost through NH 3 volatilization (Bouwman et al., 2002). Moreover, the reduction of NH 3 emission from field-applied manure draws attention since it contributes largely to the overall NH 3 volatilization from livestock production. Knowledge of NH 3 emission from fertilising activities becomes essential in the N balance computation to finally improve N efficiency in crop pro- duction: distortions in the estimation of the NH 3 losses could lead to a re- duction in the crop production (overestimation), or in environmental issues as N runoff or nitrate leaching (underestimation). The main factors influencing the total amount of NH 3 lost from liq- uid manure are the concentration of NH 3 at the liquid surface and the transfer of NH 3 from the surface to the atmosphere, both are func- tions of the meteorological conditions, i.e., solar radiation, air temper- ature, wind speed and field surface roughness (Sommer and Olesen, 2000; Søgaard et al., 2002). These factors are strongly related to the characteristics of slurry as N content, pH and dry matter, to the pres- ence and complexity of the canopy, to the physical and chemical char- acteristics of the soil (Sommer and Christensen, 1991; Génermont and Cellier, 1997; Sommer and Hutchings, 2001). The area covered by slurry and its exposure time are also key aspects influencing the NH 3 emission, i.e. field application methods, presence or absence of incorporation and infiltration rate into the soil (Sommer and Jacobsen, 1999; Huijsmans et al., 2003; Misselbrook et al., 2005; Science of the Total Environment 449 (2013) 126–133 ⁎ Corresponding author. Tel.: +39 02 50316612; fax: +39 02 50316575. E-mail address: marco.carozzi@unimi.it (M. Carozzi). 0048-9697/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.scitotenv.2012.12.082 Contents lists available at SciVerse ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv