In order to evaluate changes in chemical properties of a Xanthic Hapludox managed under pasture, using two rotational systems, this research was performed during the rainy and dry seasons, one with Brachiaria brizantha (system I) and other with Panicum maximum (system II), in 1996 and 1997. The experimental design was completely randomized, with treatments arranged in subdivided plots, considering periods as subplots within each year, and years as subplots within each forage. Twelve replicates were utilized, and data were collected during the rainy and dry seasons. The organic material, incorporated into the soil through vegetable and animal residues, influenced positivelly the chemical characteristics. Except for Al, levels of Ca, Mg, K, P, N, C, OM and pH increased during 1997. Comparing both the Brachiaria brizantha and Panicum maximum system, the levels of nutrients increased in the rainy season, with the exception for P and Ca.
Panicum maximum; Brachiaria brizantha; pasture system; soil fertility