The use of gypsum in context of exchangeable acidity in subsurface has provided the improvement of root environment, positive influence on crop yields. Therefore, the aim of this study was to evaluate the potential of the mined gypsum from the Araripe region in increasing the exchangeable Ca and also the reduction of exchangeable Al in subsurface, and increase in biomass production of varieties of elephant grass. The experiment was composed of three varieties of elephant grass, such as, Cameroon, Gramafante and Roxo in the presence and absence of mined gypsum through a factorial arrangement (3 x 2), with treatments arranged in 4 randomized blocks. The levels of Ca2+, S-SO4(2-), Al3+ and also its saturation were not affected by the application of mined gypsum in the soil subsurface layer. The application of mined gypsum reduced the pH of the soil subsurface layer. The growing of Cameroon variety promoted the increase in soil pH, reducing the Al saturation. The Cameroon and Gramafante had high dry matter yields, but only the Cameroon variety presented response to application of gypsum, which reached 33 Mg ha-1.
movement of cations; acidity subsurface; gypsite; Pennisetum purpureum Schum
