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Understanding the initial mineral N status and mineralisation potential of a field at a rich spatial density could improve key production outcomes. This study does not however consider the practical implications of sampling and testing soil characteristics to fine a degree of resolution, and spatial application of N fertilisers. While these results are for a single paddock, they demonstrate that in this circumstance the implementation of VRN significantly improved environmental outcomes without impacting gross margins. Scenario 5 resulted in lower residual soil N at harvest and higher gross margins than Scenario 2 for both irrigated and non-irrigated systems. The APSIM-Wheat and AQUACROP models were calibrated for the Sakha 95 cultivar using phenological data, grain and biomass yield, and genetic parameters based on field observation. By contrast, the approach of Scenario 1 had consistently higher residual soil N at harvest, a leaching risk factor, compared to other scenarios. APSIM-Wheat and AQUACROP can be used to drive the best management strategies in terms of N fertilizer and water regime for wheat under Egyptian conditions. Predictions showed that yield was comparable between management scenarios in most years. The strategies were based on different levels of knowledge of spatial soil N supply and ranged from 1) standard N rate regardless of soil N level, 2) field average soil mineral-N level, 3) spatially variable mineral-N, 4) spatially variable mineralisable N and 5) both spatially variable mineral and mineralisable N. These data were used in APSIM, a systems model, to estimate production outcomes under five different N management strategies in an irrigated and non-irrigated maize cropping system over 35 years. Gridded soil samples from a cropping paddock in Hawke’s Bay, New Zealand, were characterised for initial mineral N and a bioassay used to quantify N mineralisation potential. For ratoon crops at a given location (site and soil), the DYP and soil organic matter terms of. Harrison, MT ORCID: 0000-0001-7425-452X, De Antoni Migliorati, M, Rowlings, D, Doughterty, W, Grace, P and Eckard, RJ 2018, Modelling biomass, soil water content and mineral nitrogen in dairy pastures: a comparison of DairyMod and APSIM, paper presented at the Australasian Dairy Science Symposium, 21-23 November 2018, Palmerston North, New Zealand. residual mineral N, and N mineralisation). Environmental Nitrogen Losses, SIX EASY STEPS, APSIM. Despite potential benefits there has been comparatively little work in NZ looking at the value proposition underpinning VRN and understanding the importance of soil N pools (e.g. Variable rate nitrogen (VRN) management strategies seek to optimise the N supply to match crop demand, both to maximise farmer profitability and minimise environmental risks.