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Simulation models are extensively used to predict agricultural productivity and greenhouse gas emissions. However, the uncertainties of (reduced) model ensemble simulations have not been assessed systematically for variables affecting food security and climate change mitigation, within multi-species agricultural contexts. We report an international model comparison and benchmarking exercise, showing the potential of multi-model ensembles to predict productivity and nitrous oxide (N

There is a lack of information on how placement in soil and nitrification inhibitors affects nitrous oxide (N₂O) and ammonia (NH₃) emissions from pig slurry (PS) applied under no-till (NT) conditions. Our objective was to determine the impact of injecting PS and treating it with the nitrification inhibitor dicyandiamide (DCD) on NH₃ and N₂O emissions from soils under NT in subtropical southern Brazil. The emissions of these gases were compared for shallow (∼ 10 cm) injection and surface broadcasting of PS with and without DCD (8.1–10.0 kg ha⁻¹; 6.5–8.4% of applied NH₄–N). Measurements were made at two sites during two summer growing seasons under NT corn crops. Injection reduced NH₃ volatilization by 70% but increased N₂O emissions 2.4-fold (from 2628 to 6198 g N₂O N ha⁻¹) compared with surface broadcast application. Adding DCD to PS inhibited nitrification and reduced N₂O emissions by an average of 28% (730 g N₂O–N ha⁻¹) for surface broadcast and 66% (4105 g N₂O–N ha⁻¹) for injection but did not increase NH₃ volatilization. Consequently, N₂O emission factors were much higher for injection (3.6%) than for surface broadcast (1.3%) application and were reduced (0.9%) when DCD was added to injected PS. In conclusion, the injection of DCD-treated slurry is a recommendable practice for reducing NH₃ and N₂O emissions when applying PS on NT corn in southern Brazil.