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Soil fertilisation affects greenhouse gas emissions. The objective of this study was to compare the effect of different fertilisation strategies on N 2 O, CH 4 emissions and on ecosystem respiration (CO 2 emissions), during different periods of rice cultivation (rice crop, postharvest period, and seedling) under Mediterranean climate. Emissions were quantified weekly by the photoacoustic technique at two sites. At Site 1 (2011 and 2012), background treatments were 2 doses of chicken manure (CM): 90 and 170 kg NH 4 + -N ha − 1 (CM-90, CM-170), urea (U, 150 kg N ha − 1 ) and no-N (control). Fifty kilogram N ha − 1 ammonium sulphate (AS) were topdress applied to all of them. At Site 2 (2012), background treatments were 2 doses of pig slurry (PS): 91 and 152 kg NH 4 + -N ha − 1 (PS-91, PS-152) and ammonium sulphate (AS) at 120 kg NH 4 + -N ha − 1 and no-N (control). Sixty kilogram NH 4 + -N ha − 1 as AS were topdress applied to AS and PS-91. During seedling, global warming potential (GWP) was ~ 3.5–17% of that of the whole rice crop for the CM treatments. The postharvest period was a net sink for CH 4 , and CO 2 emissions only increased for the CM-170 treatment (up to 2 Mg CO 2 ha − 1 ). The GWP of the entire rice crop reached 17 Mg CO 2 -eq ha − 1 for U, and was 14 for CM-170, and 37 for CM-90. The application of PS at agronomic doses (~ 170 kg N ha − 1 ) allowed high yields (~ 7.4 Mg ha − 1 ), the control of GWP (~ 6.5 Mg CO 2 -eq ha − 1 ), and a 13% reduction in greenhouse gas intensity (GHGI) to 0.89 kg CO 2 -eq kg − 1 when compared to AS (1.02 kg CO 2 -eq kg − 1 ). [ABSTRACT FROM AUTHOR]

• Nitrification inhibitor DMPSA was tested under tillage (CT) and no-tillage (NT). • N 2 O emissions due to fertilization were completely abated by DMPSA in NT. • DMPSA decrease amoA and induce nosZI gene abundances. • Crop yield and quality were not affected by DMPSA application. • NT was more sustainable than CT in terms of CO 2 emissions. Agricultural sustainability is compromised by nitrogen (N) losses caused by soil microbial activity. Nitrous oxide (N 2 O) is a potent greenhouse gas (GHG) produced as consequence of nitrification and denitrification processes in soils. Nitrification inhibitors (NI) as 3,4-dimethylpyrazole-succinic acid (DMPSA) are useful tools to reduce these N losses from fertilization. The objective of this work was to test the efficiency of DMPSA in two different tillage management systems, conventional tillage (CT) and no-tillage (NT), in a winter wheat crop under Humid Mediterranean conditions. N fertilizer was applied as ammonium sulphate (AS) with or without DMPSA in a single or split application, including an unfertilized treatment. GHG fluxes (N 2 O, CO 2 and CH 4) were measured by the closed chamber method. amoA and nosZI genes were quantified by qPCR as indicators of nitrifying and denitrifying populations. Nitrification was inhibited by DMPSA in both CT and NT, while the higher water filled pore space (WFPS) in NT promoted a better efficiency of DMPSA in this system. This higher efficiency might be due to a greater N 2 O reduction to N 2 as result of the nosZI gene induction. Consequently, DMPSA was able to reduce N 2 O emissions down to the unfertilized levels in NT. Provided that NT reduced CO 2 emissions and maintained crop yield compared to CT, the application DMPSA under NT management is a promising strategy to increase agro-systems sustainability under Humid Mediterranean conditions. [ABSTRACT FROM AUTHOR]