Advancing understanding of in-river phosphorus dynamics using an advection–dispersion model (ADModel-P)

•Advance the understanding of in-stream phosphorus transformation processes.•Use easily attainable field data to generate empirical relations of process rates.•Extensive scope for transferability to other rivers.•At which times rivers are net sources or sinks and which processes might dominate.•Adsorption-desorption and resuspension influence investigated phosphorus the most.