Dissolved reactive phosphorus played a limited role in phosphorus transport via runoff, throughflow and leaching on contrasting cropping soils from southwest Australia

•Dissolved reactive P played a limited role in P transport compared to PP and dissolved unreactive P (DURP).•Major proportion of the DURP fraction is fine colloidal (0.2–0.45um size class).•Phosphorus is associated with soil particles or soil colloids in runoff, through flow, leachate and soil solution.•Higher level of Exchangeable Na and exchangeable sodium percentage affect subsoil P transport in loam soil.