The input of phosphorus (P) in the runoff of fertilized agricultural soils is associated with the eutrophication of water bodies. In order to study P transference from a Typic Haplortox to the water bodies the runoff, sediment, and soil samples of an experimental field were evaluated after application of mineral fertilizer and sewage sludge. The amounts of dissolved organic and inorganic, particulate and total P in runoff were evaluated. Total and available P were measured in sediments. In the soil, besides resin P, the extracted levels of Al, Fe, and P were also evaluated, for estimating P adsorption capacity (PAC) and the degree of P saturation (DSP). The application of sewage sludge increased the levels of P in soil resulting in an increase of DSP. The levels of P detected in the runoff did not correlated to DSP and high levels of P in the soil with sewage sludge do not increased its transportation. Rainfall intensity had no effect on the concentrations of P forms in runoff of soils with application of sewage sludge. The total P losses by erosion were higher in runoff than in sediments.
agriculture; eutrophication; organic waste; water quality
