Nitrous oxide emissions with enhanced efficiency and conventional urea fertilizers in winter wheat

Abstract Optimizing nitrogen fertilizer management can reduce nitrous oxide (N 2 O) emissions. This study tested if split applying enhanced efficiency fertilizers (EEFs) resulted in lower N O emissions than equivalent rates of urea at planting. In semiarid southern Alberta, field trials were conducted during three years (planting to harvest) rainfed winter wheat crops. Annual ranged from 146 176 kg ha ?1 . Fertilizer types urea, and EEFs (polymer-coated with urease nitrification inhibitors, a inhibitor). Each type was applied ways: 100% banded planting, 30% planting 70% broadcast late fall, Feekes growth stage 4 (GS4, post-tiller formation, entering the greening up phase early spring). Nitrous measured using static chambers between sub-weekly monthly harvest. Over years, cumulative 0.16 1.32 factors 0.009 0.688%. Cumulative did not differ types, but they when GS4 compared fall ( P ? 0.10). Our suggests that do crops, well-timed application majority after minimize