Phosphorus is one of the limiting elements in acid soils, so the incorporation of strategies for its cycling within an agroecosystem is one of the key variables, in order to optimize agricultural production. The dynamics of phosphorus in a maize-livestock agroecosystem were evaluated under the types of forages introduced: Brachiaria dyctioneura (Bd), a grass and Centrosema macrocarpum (Cm), a legume, which in turn served as associated perennial coverages maize grown with direct sowing. The dynamics of this element are contrasted in the savanna of natural vegetation (SN). It determined the availability of this element in the soil (0-15 cm), as well as the total P content in the excreta of the cattle and in the green fraction of the vegetation during the dry season, after the harvest of the corn, when the cattle a grazing is introduced. We analyzed the bromatological quality of livestock and the daily gain of weight in livestock (GDP). Concentrations of total P in the plant biomass varied according to the quality of the pasture forage, being higher in the Cm. This significantly affected (p<0.01) the excreta P and the available P of the soil, which resulted in a higher GDP. In the savanna conditions, P cycling in the subsystems of soil-plant-animal, is more effective when a forage legume is used as Cm, since it favors the incorporation of P through the excreta and by the decomposition of his necromass. ; El fósforo constituye uno de los elementos limitantes en suelos ácidos, por lo que la incorporación de estrategias para su ciclaje dentro de un agroecosistema es una de las variables claves, a fin de optimizar la producción agropecuaria. Se evaluó, la dinámica del fósforo en un agroecosistema conservacionista maíz-ganado, bajo dos tipos de forrajes introducidos: Brachiaria dyctioneura (Bd), una gramínea y Centrosema macrocarpum (Cm), una leguminosa, que a su vez se desempeñaron como coberturas perennes asociadas al maíz cultivado con siembra directa. Se contrastó la dinámica de este elemento en la sabana de ...