Behavior exhibited by the exchangeable sodium and magnesium at 63 days after application of cassava waste water (DAM) is likely related to a competition between these cations and exchangeable potassium and calcium due to the high concentration of the last two elements in the cassava waste water (Table 2). When added to soil, they may have been adsorbed by the exchange complex, displacing Behavior exhibited by the exchangeable sodium and magnesium at 63 days after application of cassava waste water (DAM) is likely related to a competition between these cations and exchangeable potassium and calcium due to the high concentration of the last two elements in the cassava waste water (Table 2). When added to soil, they may have been adsorbed by the exchange complex, displacing