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O presente estudo teve como objetivo avaliar a qualidade do lixiviado de solos que receberam doses de vinhaça em diferentes tempos de incubação. Para isso, em 27 colunas de PVC de 20 x 110 cm (diâmetro x altura), foram reproduzidos três solos classificados como Nitossolo Háplico, Argissolo Amarelo e Espodossolo Cárbico, com horizontes, espessuras e densidades semelhantes à original. Os solos foram tratados com vinhaça em doses equivalentes a 0 (testemunha), 350 e 700 m³ ha-1 e submetidos aos tempos de incubação de 30 e 60 dias. Nos efluentes coletados, foi realizada análise de K, Ca, Mg e Na, e os dados obtidos, submetidos à análise multivariada, a 5% de probabilidade. Os resultados indicaram efeito significativo para as variáveis K, Ca, Mg e Na com respeito ao solo, dose e tempo de incubação, exceto o Na para a causa de variação solo. De maneira geral, os menores valores das concentrações de cátions presentes nos lixiviados foram obtidos no Nitossolo, maior fração argila, seguido do Espodossolo devido ao horizonte espódico. Os valores dos cátions do lixiviado, comparados com os presentes na vinhaça in natura, foram significativamente reduzidos, indicando que os solos tiveram elevado poder de retenção.The present study had the objective of evaluating leachate quality from soils that received different vinasse doses and incubation time. In twenty-seven 20' 110 cm (diameter ' height) PVC columns, three soils, classified as Haplic Nitosol, Yellow Argisol and Carbic Spodosol, were reproduced with horizons, thickness and densities similar to original. The soils were treated with vinasse in doses equivalent to 0 (control), 350 and 700 m³ ha-1 and submitted to incubation time of 30 and 60 days. Collected effluents were analyzed for K, Ca, Mg and Na contents, and data evaluated by multivariate statistical analysis, at 5% level. The results pointed out significant effect for K, Ca, Mg and Na with regard to soil, dose and incubation time, except for Na in relation to soil. The lowest values for cation concentrations in the leachate were obtained for Nitosol which presented the highest clay fraction, followed by Spodosol due to the spodic horizon. When compared to vinasse in nature, leachate cation concentrations were significantly reduced indicating high retention power of the soils.

Coffee wastewater (CWW) is rich in organic mater and nutrients, but if applied in high doses, CWW may affect the soil sorptive complex balance and contaminate water tables through leaching process. This paper aims to evaluate the leachate composition and the chemical changes of the soil after application of increasing CWW doses. Therefore, CWW was applied in 12 PVC columns with 100 mm diameter and 800 mm height filled up with Yellow Latosolic Argisoil at doses of 1070 (control, dose 1), 214 (dose 2), 642 (dose 3) and,1070 mL (dose 4), corresponding to 1, 3 and 5 times the necessity of K (80g K2O plants-1) required by coffee tree in production. After CWW application, two leaching depths were applied, at 60 (sheet 1) and 75 days (sheet 2), using water and collecting leachate for further analysis of OCD, EC and soluble K, Na, Ca and Mg. After the incubation period, soil samples were collected 0-15; 15-30; 30-45 and 45-60 cm deep for electric conductivity of saturate paste extract (ECs) and pH in water (1:2,5) determination, along with K, Na, Ca e Mg analysis. CWW application in the soil changed the chemical characteristics of pH, ECs, K and Na. In leachate, there was variation in CE, K, Na, Ca and Mg related to incubation time. [ABSTRACT FROM AUTHOR]