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[en] Drip irrigation combined with nitrogen (N) fertigation is applied in order to save water and improve nutrient efficiency. Nitrification inhibitors reduce greenhouse gas emissions. A field study was conducted to compare the emissions of nitrous oxide (N_2O), carbon dioxide (CO_2) and methane (CH_4) associated with the application of N fertiliser through fertigation (0 and 50 kg N ha"−"1), and 50 kg N ha"−"1 + nitrification inhibitor in a high tree density Arbequina olive orchard. Spanish Arbequina is the most suited variety for super intensive olive groves. This system allows reducing production costs and increases crop yield. Moreover its oil has excellent sensorial features. Subsurface drip irrigation markedly reduced N_2O and N_2O + N_2 emissions compared with surface drip irrigation. Fertiliser application significantly increased N_2O + N_2, but not N_2O emissions. Denitrification was the main source of N_2O. The N_2O losses (calculated as emission factor) ranging from − 0.03 to 0.14% of the N applied, were lower than the IPCC (2007) values. The N_2O + N_2 losses were the largest, equivalent to 1.80% of the N applied, from the 50 kg N ha"−"1 + drip irrigation treatment which resulted in water filled pore space > 60% most of the time (high moisture). Nitrogen fertilisation significantly reduced CO_2 emissions in 2011, but only for the subsurface drip irrigation strategies in 2012. The olive orchard acted as a net CH_4 sink for all the treatments. Applying a nitrification inhibitor (DMPP), the cumulative N_2O and N_2O + N_2 emissions were significantly reduced with respect to the control. The DMPP also inhibited CO_2 emissions and significantly increased CH_4 oxidation. Considering global warming potential, greenhouse gas intensity, cumulative N_2O emissions and oil production, it can be concluded that applying DMPP with 50 kg N ha"−"1 + drip irrigation treatment was the best option combining productivity with keeping greenhouse gas emissions under control. - Highlights: • Subsurface drip irrigation mitigated N_2O emission compared with drip irrigation. • Nitrogen application didn't increase N_2O–N nor (N_2O + N_2)–N emissions. • The olive orchard acted as a net CH_4 sink for all the treatments. • DMPP reduced the cumulative N_2O, N_2O + N_2 and CO_2 emission compared to the control. • The N50 + DI + DMPP treatment reduced emissions at a high yield (2737 kg oil ha"−"1).