N source and tillage management: Effect on nitrous oxide emissions

A split plot field experiment was conducted in a barley (Hordeum vulgare L.) crop in central Spain. The main factor was tillage (conventional tillage versus no tillage), while in the subplots we evaluated three treatments: conventional fertilizers (urea and calcium ammonium nitrate), fertilizers with urease and/or nitrification inhibitors, and a control.

Nitrous oxide (N2O) emissions and yields were measured. Our results indicated that the combination of no tillage and the use of urease and/or nitrification inhibitors was an effective management to decrease yield-scaled emissions (without yield penalties and even increasing yields under NT) under rainfed Mediterranean conditions.