Using DMPP with cattle manure can mitigate yield-scaled global warming potential under low rainfall conditions

• Published in: Environmental pollution (1987) 2023-01, Vol.316, p.120679, Article 120679
• Main Authors: Guardia, Guillermo, Abalos, Diego, Mateo-Marín, Noemí, Nair, Drishya, Petersen, Søren O.
• Format: Article
• Language: English
• Subjects: Carbon footprint; Crop recovery efficiency; Enhanced-efficiency fertilisers; Nitrogen surplus; Pollution swapping; Vizura
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2022.120679

Organic fertilisers can reduce the carbon (C) footprint from croplands, but adequate management strategies such as the use of nitrification inhibitors are required to minimise side-effects on nitrogen (N) losses to the atmosphere or waterbodies. This could be particularly important in a context on changing rainfall patterns due to climate change. A lysimeter experiment with maize (Zea mays L.) was set up on a coarse sandy soil to evaluate the efficacy of 3,4-dimethylpyrazole phosphate (DMPP) to mitigate nitrous oxide (N2O) emissions, nitrate (NO3−) leaching losses and net global warming potential from manure, with (R+) and without (R-) simulated rainfall events. Soil water availability was a limiting factor for plant growth and microbial processes due to low rainfall during the growing season. Nitrification was effectively inhibited by DMPP, decreasing topsoil NO3− concentrations by 28% on average and cumulative N2O losses by 82%. Most of the N2O was emitted during the growing season, with annual emission factors of 0.07% and 0.95% for manure with and without DMPP, respectively. Cumulative N2O emissions were 40% higher in R-compared to R+, possibly because of the higher topsoil NO3− concentrations. There was no effect of DMPP or rainfall amount on annual NO3− leaching losses, which corresponded to 12% of manure-N and were mainly driven by the post-harvest period. DMPP did not affect yield or N use efficiency (NUE) while R-caused severe reductions on biomass and NUE. We conclude that dry growing seasons can jeopardize crop production while concurrently increasing greenhouse gas emissions from a sandy soil. The use of nitrification inhibitors is strongly recommended under these conditions to address the climate change impacts. [Display omitted] •DMPP (Vizura®) with cattle manure tested under low and normal rainfall conditions.•Drier conditions increased N2O losses without reducing NO3− leaching.•Vizura® mitigated N2O emissions by 82% with no effect on NO3− leaching.•Low rainfall resulted in severe yield and NUE penalties.•Vizura® lessened area-scaled and yield-scaled GWP through N2O loss abatement.