The effect of distinct doses of phosphorus was evaluated on the diffusion of this element in soil samples from the State of Alagoas. The experiment was performed in the laboratory of the Centro de Ciências Agrárias of the Federal University of Alagoas, Rio Largo, AL. The soils were classified as a compacted Yellow Latossol, Grey Argissoil, Fluvic Neosoil, Quartzanic Neossoil and ortic Chromic Luvissoil. Chemical, physical and mineralogical analyses had been made. The determination of the remaining P was made in the equilibrium solution. The maximum capacity of adsorption was determined through the remaining phosphorus, using PVC rings which were used as diffusion chambers. The doses of phosphorus had been equivalent to 0, 10, 20 and 30% of the maximum capacity of adsorption. The evaluation of the diffusive flow of phosphorus in the soils was carried out through papers of anionic exchange, using filter-papers saturated with the iron oxide. The experiment was constituted of a factorial arrangement (6 x 4), corresponding to six soils and four doses of phosphorus. The most sandy soils and the largest dose always showed the largest diffusive fluxes of phosphorus.
CMAP; FCP; diffusion
