Fig. 6 Effect of (a) nonlinear equilibrium sorption (S = KCn) and (b) nonequilibrium sorption [
C/t = ß(KC - S)] on the ratio 
of maximum concentrations in the sandy soil. The parameters n and ß are the nonlinearity constant of the sorption isotherm and the nonequilibrium rate coefficient, respectively. The water flux for these simulations was q = 0.5 cm d-1