Nicholas Howell

1 Introduction Phosphorus (P) is an essential macronutrient for plant growth and function (de Bang et al. 2021). Since biogeochemical processes in the soil limit root P uptake, excessive, compensatory soil P applications are common, increasing the risk for subsequent nutrient run-off or leaching into groundwater, which at the global scale can threaten the stability of regulating planetary boundaries (Zou et al. 2022; Rockström et al. 2023).

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