Sugarcane Vinasse Cations Dynamics in Cerrado Soils, Brazil

The application of vinasse in sugarcane plantations has increased, mainly in the form of fertigation, as a form of organic and mineral supplementation. Several factors, such as soil type, can affect the migration and retention of chemicals in such supplements. Based on the hypothesis that in natura vinasse applied to sandy soil has a greater nutrient loss potential in the Cerrado soil profile than that of clay soil, we aimed to elucidate the behavior of potassium, sodium, calcium, and magnesium ions present in the vinasse along the surface profile of a clay Latosol and a sandy Latosol from the Cerrado region. The experiment was conducted at the Irrigation and Hydraulics Laboratory of the Federal Institute Goiano, Campus Rio Verde, Goias, Brazil. Application of vinasse was examined in a Dystroferric Red Latosol (Oxisol) (dfRL) of medium texture and a Dystrophic Red Latosol (Oxisol) (dRL) of sandy texture contained in rigid PVC columns. Samples (30 cm3) of effluent were collected to determine K+, Na+, Ca2+, and Mg2+ levels. We found that these ions had greater retention in dfRL than in dRL owing to their higher clay interaction. The highest interaction between the liquid and solid phase of dfRL was seen in Ca2+, followed by K+, Na+, and Mg2+, whereas in dRL, K+ showed the highest interaction, followed by Ca2+, Na+, and Mg2+. Larger volumes of effluent are required for fertigation with vinasse in dfRL to provide the required levels of Mg2+, K+, and Ca2+ in the soil profile.