Accumulation of phosphorus (P) in agricultural topsoils can contribute to leaching of P which may cause eutrophication of surface waters. An understanding of P mobilization processes in the plough layer is needed to improve agricultural management strategies. We compare leaching of total dissolved and particulate P through the plough layer of a typical Danish sandy loam soil subjected to three different P fertilizer regimes in a long-term field experiment established in 1975. The leaching experiment used intact soil columns (20cm diameter, 20cm high) during unsaturated conditions. The three soils had small to moderate labile P contents, expressed by water-extractable P (3.6-10.7mg/kg), Olsen P (11-28mg/kg) and degree of P saturation (DPS) (25-34. Mobilization of total dissolved P (TDP) increased significantly (P