Effect of a Nitrapyrin-Based Nitrification Inhibitor on Yield and Gaseous Emissions from a Maize-Ryegrass Rotation, Fertilized with Two Slurry Types

Livestock is responsible for about 14.5% of anthropogenic green- house gases (GHGs), notably methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O), with N2O being the most potent. Approximately 40% of livestock GHG emissions come from manure management, which also significantly emits ammonia (NH3). Manure distribution technique, slurry characteristics, and envi- ronmental conditions impact field fertilization emissions. Direct injection can reduce NH3 emissions by up to 90% but may increase N2O emissions. The LIFE CLINMED-FARM project in Italy tested a nitrapyrin-based nitrification inhibitor (NI) on a cattle farm. Plots fertilized with cattle slurry and digestate, with and without NI, were monitored. The NI significantly reduced cumulative N2O emissions by 43.5% and increased maize and ryegrass yields by 11% and 6%, respectively, although these yield increases were not statistically signifi- cant. NH3 emissions were consistently low, representing 0.07% of distributed nitrogen for maize and 0.4% for ryegrass