Cation exchange capacity of organic and inorganic colloids of latosols from the state of Paraná

Abstract

Cation exhange capacity (CEC) and organic carbon values from 39 latosols from the state of Paraná were used to quantify the contribution of the organic and inorganic colloids to the CEC of the soils. The data were adjusted to a linear regression model, where the angular coefficient determined the contribution of the organic colloids and the linear regression coefficient determined the contribution of the inorganic colloids. The mathematical mode presented high coefficients of determination (R²>0,9) for the latosols. In more than 50% of the profiles studied, the CEC values due to the organic colloids varied from 400 to 500 cmolc.kg^-1, but CEC values from 200 to 800 cmolc.kg^-1 were observed.