Predicting Freundlich adsorption isotherm of atrazine on Japanese soils

It was possible to predict the amounts of atrazine adsorption on Japanese s oils by deriving predicting equations from the value of the initial concent ration of atrazine applied to the soils containing less than 70 g kg(-1) ca rbon. The equations predicted the values of Freundlich isotherm coefficient s, log K-F and 1/n. Using the linear correlation between log K-F and 1/n fo r atrazine adsorption, Freundlich adsorption isotherm could be represented by using log K-F as a parameter. Predicting equations for log K-F were deri ved from the soil physicochemical properties by multivariate analyses. Dire ct and indirect regressions to derive the predicting equations for log K-F were examined on the analyses. The better predicting equations were as foll ows; 1/n=-0.16Xlog K-F + 0.99, log K-F=0.51 + 0.31 X OM + 0.08 X TE + 0.06 X XA + 0.04 X XC, where OM, TE, XA, and XC denote the organic matter factor , the texture factor, the exchangeable acidity factor, and the exchangeable cations factor, respectively. These predicting equations estimated well ex perimental values of log K-F and 1/n.