Alterações nos atributos químicos em latossolos de diferentes texturas cultivados com cana-de-açúcar e adição de vinhaça

Abstract

To produce ethanol from sugar cane, it generates large amounts of waste, among which stands out the vinasse, which despite being excellent source of nutrients for plants, is considered a problem for the sugar and alcohol sector due to large volume generated. Applying this byproduct indiscriminately in crops may contaminate the soil, surface water and subsuperificais. Thus, the present study aimed to evaluate the distribution of K, P, Ca + Mg, total N, Ctotal in the cultivated soil profile with cane sugar undergoing application of vinasse. For this purpose, soil samples were collected at seven depths (0-5, 5-10, 10-20, 20-40, 40-60, 60-80 and 80-100 cm in six commercial plots of the plant Pantanal, located in municipality of Jaciara-MT. Selected plots include the following treatments: three soil textural classes (sandy-medium, medium-loamy and clay) and three conditions for the application of vinasse (without application of vinasse, two years of implementation, and fifteen years of application of vinasse). These samples Ca, Mg, K, P, and total N, Ctotal were determined. It was observed that the application of vinasse is made of heterogeneous, coming to be applied in 16% of clay area and 40% of the average-clay vinasse more than recommended by the technical standards. The distribution of the attributes studied in the soil profile is affected by the application of vinasse, especially in soil with lower clay content. Application of vinasse for the fifteen consecutive years in compared to the areas that had no applications, increase the K and P stocks independent texture depth of the soil studied. In the edafoclimatic conditions studied the Ctotal and Ntotal stocks are unchanged with consecutive application of vinasse for the fifteen years independent of soil textures studied. The tillage management of vinasse (dose and frequency) should be differentiated according to soil clay content, especially for consecutive long-term applications.