A case study on precision nitrogen management in Dutch arable farming

Throughout Europe new environmental laws are being implemented to limitnitrogen (N) fertilization on arable land. This is particularly relevant in TheNetherlands where arable farms rank among the most intensively managed in theworld. An efficient use of inputs is therefore crucial. Precision agricultureaims at increasing this efficiency by incorporating spatial and temporalvariation into fertilizer management. A method developed for this purpose isevaluated, based on two fertilizer experiments conducted in consecutive years(1998–1999) on different winter wheat fields (Triticumaestivum L.). A simulation model and real-time weather data were usedto monitor soil mineral N levels in the experimental fields. Spatial variationwas incorporated through management units, which were defined in terms of waterregimes and N dynamics. Early warning was provided when soil mineral Nconcentrations dropped below a critical threshold. Used as atrigger, this information served to optimize the timing offour consecutive N fertilizations. Fertilizer rates were determined throughexploratory simulations, which calculated the amount of mineral N required undernormal conditions. Compared to conventional management,fertilizer input was reduced by 15–27% without affecting grainyield. Grain quality was either not affected (1999) or significantly increased(1998; P < 0.01). Soil mineral N residues measured afterharvest were consistently lower under precision management. This is importantsince leaching of nitrates mainly occurs during winter when a precipitationsurplus is present. Results provide an illustration of efficiency gains attainedthrough precision N management. They also underline the relevance of managingtemporal variation (along with spatial variation) on farms applying intensiveand dynamic management strategies

[Stickeen, etc.], [ca.1887], Image 23

https://scholarlycommons.pacific.edu/jmn-st1/1022/thumbnail.jp